Merge branch 'google:master' into image-classification-python-impl

mediapipe/calculators/util/BUILD

@@ -143,9 +143,7 @@ mediapipe_proto_library(
 cc_library(
     name = "packet_frequency_calculator",
     srcs = ["packet_frequency_calculator.cc"],
-    visibility = [
+    visibility = ["//visibility:public"],
-        "//visibility:public",
-    ],
     deps = [
         "//mediapipe/calculators/util:packet_frequency_calculator_cc_proto",
         "//mediapipe/calculators/util:packet_frequency_cc_proto",
@@ -190,9 +188,7 @@ cc_test(
 cc_library(
     name = "packet_latency_calculator",
     srcs = ["packet_latency_calculator.cc"],
-    visibility = [
+    visibility = ["//visibility:public"],
-        "//visibility:public",
-    ],
     deps = [
         "//mediapipe/calculators/util:latency_cc_proto",
         "//mediapipe/calculators/util:packet_latency_calculator_cc_proto",

mediapipe/calculators/util/labels_to_render_data_calculator.cc

@@ -184,6 +184,17 @@ absl::Status LabelsToRenderDataCalculator::Process(CalculatorContext* cc) {
     text->set_left(label_left_px_);
     text->set_baseline(label_baseline_px + i * label_height_px_);
     text->set_font_face(options_.font_face());
+    if (options_.outline_thickness() > 0) {
+      text->set_outline_thickness(options_.outline_thickness());
+      if (options_.outline_color_size() > 0) {
+        *(text->mutable_outline_color()) =
+            options_.outline_color(i % options_.outline_color_size());
+      } else {
+        text->mutable_outline_color()->set_r(0);
+        text->mutable_outline_color()->set_g(0);
+        text->mutable_outline_color()->set_b(0);
+      }
+    }
   }
   cc->Outputs()
       .Tag(kRenderDataTag)

mediapipe/calculators/util/labels_to_render_data_calculator.proto

@@ -30,6 +30,13 @@ message LabelsToRenderDataCalculatorOptions {
   // Thickness for drawing the label(s).
   optional double thickness = 2 [default = 2];
 
+  // Color of outline around each character, if any. One per label, as with
+  // color attribute.
+  repeated Color outline_color = 12;
+
+  // Thickness of outline around each character.
+  optional double outline_thickness = 11;
+
   // The font height in absolute pixels.
   optional int32 font_height_px = 3 [default = 50];
 

mediapipe/gpu/gl_texture_buffer.cc

@@ -185,7 +185,10 @@ void GlTextureBuffer::Updated(std::shared_ptr<GlSyncPoint> prod_token) {
       << "Updated existing texture which had not been marked for reuse!";
   CHECK(prod_token);
   producer_sync_ = std::move(prod_token);
-  producer_context_ = producer_sync_->GetContext();
+  const auto& synced_context = producer_sync_->GetContext();
+  if (synced_context) {
+    producer_context_ = synced_context;
+  }
 }
 
 void GlTextureBuffer::DidRead(std::shared_ptr<GlSyncPoint> cons_token) const {

mediapipe/java/com/google/mediapipe/framework/BUILD

@@ -34,6 +34,7 @@ android_library(
 android_library(
     name = "android_framework_no_mff",
     proguard_specs = [":proguard.pgcfg"],
+    visibility = ["//visibility:public"],
     exports = [
         ":android_framework_no_proguard",
     ],

mediapipe/python/BUILD

@@ -48,6 +48,8 @@ pybind_extension(
         "//mediapipe/python/pybind:timestamp",
         "//mediapipe/python/pybind:validated_graph_config",
         "//mediapipe/tasks/python/core/pybind:task_runner",
+        "@com_google_absl//absl/strings:str_format",
+        "@stblib//:stb_image",
         # Type registration.
         "//mediapipe/framework:basic_types_registration",
         "//mediapipe/framework/formats:classification_registration",

mediapipe/python/image_test.py

@@ -15,6 +15,7 @@
 """Tests for mediapipe.python._framework_bindings.image."""
 
 import gc
+import os
 import random
 import sys
 
@@ -23,6 +24,7 @@ import cv2
 import numpy as np
 import PIL.Image
 
+# resources dependency
 from mediapipe.python._framework_bindings import image
 from mediapipe.python._framework_bindings import image_frame
 
@@ -185,6 +187,5 @@ class ImageTest(absltest.TestCase):
     gc.collect()
     self.assertEqual(sys.getrefcount(rgb_image), initial_ref_count)
 
-
 if __name__ == '__main__':
   absltest.main()

mediapipe/python/pybind/BUILD

@@ -45,6 +45,8 @@ pybind_library(
         ":util",
         "//mediapipe/framework:type_map",
         "//mediapipe/framework/formats:image",
+        "@com_google_absl//absl/strings:str_format",
+        "@stblib//:stb_image",
     ],
 )
 

mediapipe/python/pybind/image.cc

@@ -16,9 +16,11 @@
 
 #include <memory>
 
+#include "absl/strings/str_format.h"
 #include "mediapipe/python/pybind/image_frame_util.h"
 #include "mediapipe/python/pybind/util.h"
 #include "pybind11/stl.h"
+#include "stb_image.h"
 
 namespace mediapipe {
 namespace python {
@@ -225,6 +227,62 @@ void ImageSubmodule(pybind11::module* module) {
     image.is_aligned(16)
 )doc");
 
+  image.def_static(
+      "create_from_file",
+      [](const std::string& file_name) {
+        int width;
+        int height;
+        int channels;
+        auto* image_data =
+            stbi_load(file_name.c_str(), &width, &height, &channels,
+                      /*desired_channels=*/0);
+        if (image_data == nullptr) {
+          throw RaisePyError(PyExc_RuntimeError,
+                             absl::StrFormat("Image decoding failed (%s): %s",
+                                             stbi_failure_reason(), file_name)
+                                 .c_str());
+        }
+        ImageFrameSharedPtr image_frame;
+        switch (channels) {
+          case 1:
+            image_frame = std::make_shared<ImageFrame>(
+                ImageFormat::GRAY8, width, height, width, image_data,
+                stbi_image_free);
+            break;
+          case 3:
+            image_frame = std::make_shared<ImageFrame>(
+                ImageFormat::SRGB, width, height, 3 * width, image_data,
+                stbi_image_free);
+            break;
+          case 4:
+            image_frame = std::make_shared<ImageFrame>(
+                ImageFormat::SRGBA, width, height, 4 * width, image_data,
+                stbi_image_free);
+            break;
+          default:
+            throw RaisePyError(
+                PyExc_RuntimeError,
+                absl::StrFormat(
+                    "Expected image with 1 (grayscale), 3 (RGB) or 4 "
+                    "(RGBA) channels, found %d channels.",
+                    channels)
+                    .c_str());
+        }
+        return Image(std::move(image_frame));
+      },
+      R"doc(Creates `Image` object from the image file.
+
+Args:
+  file_name: Image file name.
+
+Returns:
+  `Image` object.
+
+Raises:
+  RuntimeError if the image file can't be decoded.
+  )doc",
+      py::arg("file_name"));
+
   image.def_property_readonly("width", &Image::width)
       .def_property_readonly("height", &Image::height)
       .def_property_readonly("channels", &Image::channels)

mediapipe/tasks/cc/audio/audio_classifier/BUILD

@@ -33,11 +33,12 @@ cc_library(
         "//mediapipe/framework/api2:port",
         "//mediapipe/framework/formats:matrix",
         "//mediapipe/tasks/cc:common",
-        "//mediapipe/tasks/cc/audio/audio_classifier/proto:audio_classifier_options_cc_proto",
+        "//mediapipe/tasks/cc/audio/audio_classifier/proto:audio_classifier_graph_options_cc_proto",
         "//mediapipe/tasks/cc/audio/utils:audio_tensor_specs",
-        "//mediapipe/tasks/cc/components:classification_postprocessing",
+        "//mediapipe/tasks/cc/components/containers/proto:classifications_cc_proto",
-        "//mediapipe/tasks/cc/components:classification_postprocessing_options_cc_proto",
+        "//mediapipe/tasks/cc/components/processors:classification_postprocessing_graph",
-        "//mediapipe/tasks/cc/components/containers:classifications_cc_proto",
+        "//mediapipe/tasks/cc/components/processors:classifier_options",
+        "//mediapipe/tasks/cc/components/processors/proto:classification_postprocessing_graph_options_cc_proto",
         "//mediapipe/tasks/cc/core:model_resources",
         "//mediapipe/tasks/cc/core:model_task_graph",
         "//mediapipe/tasks/cc/core/proto:inference_subgraph_cc_proto",
@@ -60,12 +61,13 @@ cc_library(
         ":audio_classifier_graph",
         "//mediapipe/framework/api2:builder",
         "//mediapipe/framework/formats:matrix",
-        "//mediapipe/tasks/cc/audio/audio_classifier/proto:audio_classifier_options_cc_proto",
+        "//mediapipe/tasks/cc/audio/audio_classifier/proto:audio_classifier_graph_options_cc_proto",
         "//mediapipe/tasks/cc/audio/core:audio_task_api_factory",
         "//mediapipe/tasks/cc/audio/core:base_audio_task_api",
         "//mediapipe/tasks/cc/audio/core:running_mode",
-        "//mediapipe/tasks/cc/components:classifier_options",
+        "//mediapipe/tasks/cc/components/containers/proto:classifications_cc_proto",
-        "//mediapipe/tasks/cc/components/containers:classifications_cc_proto",
+        "//mediapipe/tasks/cc/components/processors:classifier_options",
+        "//mediapipe/tasks/cc/components/processors/proto:classifier_options_cc_proto",
         "//mediapipe/tasks/cc/core:base_options",
         "//mediapipe/tasks/cc/core:task_runner",
         "//mediapipe/tasks/cc/core/proto:inference_subgraph_cc_proto",

mediapipe/tasks/cc/audio/audio_classifier/audio_classifier.cc

@@ -22,10 +22,11 @@ limitations under the License.
 #include "absl/status/statusor.h"
 #include "mediapipe/framework/api2/builder.h"
 #include "mediapipe/framework/formats/matrix.h"
-#include "mediapipe/tasks/cc/audio/audio_classifier/proto/audio_classifier_options.pb.h"
+#include "mediapipe/tasks/cc/audio/audio_classifier/proto/audio_classifier_graph_options.pb.h"
 #include "mediapipe/tasks/cc/audio/core/audio_task_api_factory.h"
-#include "mediapipe/tasks/cc/components/classifier_options.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/processors/classifier_options.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classifier_options.pb.h"
 #include "mediapipe/tasks/cc/core/proto/inference_subgraph.pb.h"
 #include "mediapipe/tasks/cc/core/task_runner.h"
 #include "tensorflow/lite/core/api/op_resolver.h"
@@ -33,8 +34,12 @@ limitations under the License.
 namespace mediapipe {
 namespace tasks {
 namespace audio {
+namespace audio_classifier {
+
 namespace {
 
+using ::mediapipe::tasks::components::containers::proto::ClassificationResult;
+
 constexpr char kAudioStreamName[] = "audio_in";
 constexpr char kAudioTag[] = "AUDIO";
 constexpr char kClassificationResultStreamName[] = "classification_result_out";
@@ -42,16 +47,13 @@ constexpr char kClassificationResultTag[] = "CLASSIFICATION_RESULT";
 constexpr char kSampleRateName[] = "sample_rate_in";
 constexpr char kSampleRateTag[] = "SAMPLE_RATE";
 constexpr char kSubgraphTypeName[] =
-    "mediapipe.tasks.audio.AudioClassifierGraph";
+    "mediapipe.tasks.audio.audio_classifier.AudioClassifierGraph";
 constexpr int kMicroSecondsPerMilliSecond = 1000;
 
-using AudioClassifierOptionsProto =
-    audio_classifier::proto::AudioClassifierOptions;
-
 // Creates a MediaPipe graph config that only contains a single subgraph node of
-// "mediapipe.tasks.audio.AudioClassifierGraph".
+// type "AudioClassifierGraph".
 CalculatorGraphConfig CreateGraphConfig(
-    std::unique_ptr<AudioClassifierOptionsProto> options_proto) {
+    std::unique_ptr<proto::AudioClassifierGraphOptions> options_proto) {
   api2::builder::Graph graph;
   auto& subgraph = graph.AddNode(kSubgraphTypeName);
   graph.In(kAudioTag).SetName(kAudioStreamName) >> subgraph.In(kAudioTag);
@@ -59,7 +61,8 @@ CalculatorGraphConfig CreateGraphConfig(
     graph.In(kSampleRateTag).SetName(kSampleRateName) >>
         subgraph.In(kSampleRateTag);
   }
-  subgraph.GetOptions<AudioClassifierOptionsProto>().Swap(options_proto.get());
+  subgraph.GetOptions<proto::AudioClassifierGraphOptions>().Swap(
+      options_proto.get());
   subgraph.Out(kClassificationResultTag)
           .SetName(kClassificationResultStreamName) >>
       graph.Out(kClassificationResultTag);
@@ -67,18 +70,18 @@ CalculatorGraphConfig CreateGraphConfig(
 }
 
 // Converts the user-facing AudioClassifierOptions struct to the internal
-// AudioClassifierOptions proto.
+// AudioClassifierGraphOptions proto.
-std::unique_ptr<AudioClassifierOptionsProto>
+std::unique_ptr<proto::AudioClassifierGraphOptions>
 ConvertAudioClassifierOptionsToProto(AudioClassifierOptions* options) {
-  auto options_proto = std::make_unique<AudioClassifierOptionsProto>();
+  auto options_proto = std::make_unique<proto::AudioClassifierGraphOptions>();
   auto base_options_proto = std::make_unique<tasks::core::proto::BaseOptions>(
       tasks::core::ConvertBaseOptionsToProto(&(options->base_options)));
   options_proto->mutable_base_options()->Swap(base_options_proto.get());
   options_proto->mutable_base_options()->set_use_stream_mode(
       options->running_mode == core::RunningMode::AUDIO_STREAM);
   auto classifier_options_proto =
-      std::make_unique<tasks::components::proto::ClassifierOptions>(
+      std::make_unique<components::processors::proto::ClassifierOptions>(
-          components::ConvertClassifierOptionsToProto(
+          components::processors::ConvertClassifierOptionsToProto(
               &(options->classifier_options)));
   options_proto->mutable_classifier_options()->Swap(
       classifier_options_proto.get());
@@ -119,7 +122,7 @@ absl::StatusOr<std::unique_ptr<AudioClassifier>> AudioClassifier::Create(
         };
   }
   return core::AudioTaskApiFactory::Create<AudioClassifier,
-                                           AudioClassifierOptionsProto>(
+                                           proto::AudioClassifierGraphOptions>(
       CreateGraphConfig(std::move(options_proto)),
       std::move(options->base_options.op_resolver), options->running_mode,
       std::move(packets_callback));
@@ -140,6 +143,7 @@ absl::Status AudioClassifier::ClassifyAsync(Matrix audio_block,
             .At(Timestamp(timestamp_ms * kMicroSecondsPerMilliSecond))}});
 }
 
+}  // namespace audio_classifier
 }  // namespace audio
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/audio/audio_classifier/audio_classifier.h

@@ -23,13 +23,14 @@ limitations under the License.
 #include "mediapipe/framework/formats/matrix.h"
 #include "mediapipe/tasks/cc/audio/core/base_audio_task_api.h"
 #include "mediapipe/tasks/cc/audio/core/running_mode.h"
-#include "mediapipe/tasks/cc/components/classifier_options.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/processors/classifier_options.h"
 #include "mediapipe/tasks/cc/core/base_options.h"
 
 namespace mediapipe {
 namespace tasks {
 namespace audio {
+namespace audio_classifier {
 
 // The options for configuring a mediapipe audio classifier task.
 struct AudioClassifierOptions {
@@ -39,7 +40,7 @@ struct AudioClassifierOptions {
 
   // Options for configuring the classifier behavior, such as score threshold,
   // number of results, etc.
-  components::ClassifierOptions classifier_options;
+  components::processors::ClassifierOptions classifier_options;
 
   // The running mode of the audio classifier. Default to the audio clips mode.
   // Audio classifier has two running modes:
@@ -58,8 +59,9 @@ struct AudioClassifierOptions {
   // The user-defined result callback for processing audio stream data.
   // The result callback should only be specified when the running mode is set
   // to RunningMode::AUDIO_STREAM.
-  std::function<void(absl::StatusOr<ClassificationResult>)> result_callback =
+  std::function<void(
-      nullptr;
+      absl::StatusOr<components::containers::proto::ClassificationResult>)>
+      result_callback = nullptr;
 };
 
 // Performs audio classification on audio clips or audio stream.
@@ -131,8 +133,8 @@ class AudioClassifier : tasks::audio::core::BaseAudioTaskApi {
   //     framed audio clip.
   // TODO: Use `sample_rate` in AudioClassifierOptions by default
   // and makes `audio_sample_rate` optional.
-  absl::StatusOr<ClassificationResult> Classify(mediapipe::Matrix audio_clip,
+  absl::StatusOr<components::containers::proto::ClassificationResult> Classify(
-                                                double audio_sample_rate);
+      mediapipe::Matrix audio_clip, double audio_sample_rate);
 
   // Sends audio data (a block in a continuous audio stream) to perform audio
   // classification. Only use this method when the AudioClassifier is created
@@ -162,6 +164,7 @@ class AudioClassifier : tasks::audio::core::BaseAudioTaskApi {
   absl::Status Close() { return runner_->Close(); }
 };
 
+}  // namespace audio_classifier
 }  // namespace audio
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/audio/audio_classifier/audio_classifier_graph.cc

@@ -28,12 +28,12 @@ limitations under the License.
 #include "mediapipe/framework/calculator.pb.h"
 #include "mediapipe/framework/calculator_framework.h"
 #include "mediapipe/framework/formats/matrix.h"
-#include "mediapipe/tasks/cc/audio/audio_classifier/proto/audio_classifier_options.pb.h"
+#include "mediapipe/tasks/cc/audio/audio_classifier/proto/audio_classifier_graph_options.pb.h"
 #include "mediapipe/tasks/cc/audio/utils/audio_tensor_specs.h"
 #include "mediapipe/tasks/cc/common.h"
-#include "mediapipe/tasks/cc/components/classification_postprocessing.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
-#include "mediapipe/tasks/cc/components/classification_postprocessing_options.pb.h"
+#include "mediapipe/tasks/cc/components/processors/classification_postprocessing_graph.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classification_postprocessing_graph_options.pb.h"
 #include "mediapipe/tasks/cc/core/model_resources.h"
 #include "mediapipe/tasks/cc/core/model_task_graph.h"
 #include "mediapipe/tasks/cc/core/proto/inference_subgraph.pb.h"
@@ -44,6 +44,7 @@ limitations under the License.
 namespace mediapipe {
 namespace tasks {
 namespace audio {
+namespace audio_classifier {
 
 namespace {
 
@@ -52,6 +53,7 @@ using ::mediapipe::api2::Output;
 using ::mediapipe::api2::builder::GenericNode;
 using ::mediapipe::api2::builder::Graph;
 using ::mediapipe::api2::builder::Source;
+using ::mediapipe::tasks::components::containers::proto::ClassificationResult;
 
 constexpr char kAtPrestreamTag[] = "AT_PRESTREAM";
 constexpr char kAudioTag[] = "AUDIO";
@@ -60,10 +62,9 @@ constexpr char kPacketTag[] = "PACKET";
 constexpr char kSampleRateTag[] = "SAMPLE_RATE";
 constexpr char kTensorsTag[] = "TENSORS";
 constexpr char kTimestampsTag[] = "TIMESTAMPS";
-using AudioClassifierOptionsProto =
-    audio_classifier::proto::AudioClassifierOptions;
 
-absl::Status SanityCheckOptions(const AudioClassifierOptionsProto& options) {
+absl::Status SanityCheckOptions(
+    const proto::AudioClassifierGraphOptions& options) {
   if (options.base_options().use_stream_mode() &&
       !options.has_default_input_audio_sample_rate()) {
     return CreateStatusWithPayload(absl::StatusCode::kInvalidArgument,
@@ -111,7 +112,7 @@ void ConfigureAudioToTensorCalculator(
 
 }  // namespace
 
-// A "mediapipe.tasks.audio.AudioClassifierGraph" performs audio classification.
+// An "AudioClassifierGraph" performs audio classification.
 // - Accepts CPU audio buffer and outputs classification results on CPU.
 //
 // Inputs:
@@ -129,12 +130,12 @@ void ConfigureAudioToTensorCalculator(
 //
 // Example:
 // node {
-//   calculator: "mediapipe.tasks.audio.AudioClassifierGraph"
+//   calculator: "mediapipe.tasks.audio.audio_classifier.AudioClassifierGraph"
 //   input_stream: "AUDIO:audio_in"
 //   input_stream: "SAMPLE_RATE:sample_rate_in"
 //   output_stream: "CLASSIFICATION_RESULT:classification_result_out"
 //   options {
-//     [mediapipe.tasks.audio.audio_classifier.proto.AudioClassifierOptions.ext]
+//     [mediapipe.tasks.audio.audio_classifier.proto.AudioClassifierGraphOptions.ext]
 //     {
 //       base_options {
 //         model_asset {
@@ -152,16 +153,18 @@ class AudioClassifierGraph : public core::ModelTaskGraph {
  public:
   absl::StatusOr<CalculatorGraphConfig> GetConfig(
       SubgraphContext* sc) override {
-    ASSIGN_OR_RETURN(const auto* model_resources,
+    ASSIGN_OR_RETURN(
-                     CreateModelResources<AudioClassifierOptionsProto>(sc));
+        const auto* model_resources,
+        CreateModelResources<proto::AudioClassifierGraphOptions>(sc));
     Graph graph;
-    const bool use_stream_mode = sc->Options<AudioClassifierOptionsProto>()
+    const bool use_stream_mode =
+        sc->Options<proto::AudioClassifierGraphOptions>()
             .base_options()
             .use_stream_mode();
     ASSIGN_OR_RETURN(
         auto classification_result_out,
         BuildAudioClassificationTask(
-            sc->Options<AudioClassifierOptionsProto>(), *model_resources,
+            sc->Options<proto::AudioClassifierGraphOptions>(), *model_resources,
             graph[Input<Matrix>(kAudioTag)],
             use_stream_mode
                 ? absl::nullopt
@@ -178,14 +181,14 @@ class AudioClassifierGraph : public core::ModelTaskGraph {
   // buffer (mediapipe::Matrix) and the corresponding sample rate (double) as
   // the inputs and returns one classification result per input audio buffer.
   //
-  // task_options: the mediapipe tasks AudioClassifierOptions proto.
+  // task_options: the mediapipe tasks AudioClassifierGraphOptions proto.
   // model_resources: the ModelSources object initialized from an audio
   // classifier model file with model metadata.
   // audio_in: (mediapipe::Matrix) stream to run audio classification on.
   // sample_rate_in: (double) optional stream of the input audio sample rate.
   // graph: the mediapipe builder::Graph instance to be updated.
   absl::StatusOr<Source<ClassificationResult>> BuildAudioClassificationTask(
-      const AudioClassifierOptionsProto& task_options,
+      const proto::AudioClassifierGraphOptions& task_options,
       const core::ModelResources& model_resources, Source<Matrix> audio_in,
       absl::optional<Source<double>> sample_rate_in, Graph& graph) {
     MP_RETURN_IF_ERROR(SanityCheckOptions(task_options));
@@ -236,11 +239,14 @@ class AudioClassifierGraph : public core::ModelTaskGraph {
 
     // Adds postprocessing calculators and connects them to the graph output.
     auto& postprocessing = graph.AddNode(
-        "mediapipe.tasks.components.ClassificationPostprocessingSubgraph");
+        "mediapipe.tasks.components.processors."
-    MP_RETURN_IF_ERROR(ConfigureClassificationPostprocessing(
+        "ClassificationPostprocessingGraph");
+    MP_RETURN_IF_ERROR(
+        components::processors::ConfigureClassificationPostprocessingGraph(
             model_resources, task_options.classifier_options(),
-        &postprocessing.GetOptions<
+            &postprocessing
-            tasks::components::ClassificationPostprocessingOptions>()));
+                 .GetOptions<components::processors::proto::
+                                 ClassificationPostprocessingGraphOptions>()));
     inference.Out(kTensorsTag) >> postprocessing.In(kTensorsTag);
 
     // Time aggregation is only needed for performing audio classification on
@@ -257,8 +263,10 @@ class AudioClassifierGraph : public core::ModelTaskGraph {
   }
 };
 
-REGISTER_MEDIAPIPE_GRAPH(::mediapipe::tasks::audio::AudioClassifierGraph);
+REGISTER_MEDIAPIPE_GRAPH(
+    ::mediapipe::tasks::audio::audio_classifier::AudioClassifierGraph);
 
+}  // namespace audio_classifier
 }  // namespace audio
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/audio/audio_classifier/audio_classifier_test.cc

@@ -37,17 +37,19 @@ limitations under the License.
 #include "mediapipe/tasks/cc/audio/core/running_mode.h"
 #include "mediapipe/tasks/cc/audio/utils/test_utils.h"
 #include "mediapipe/tasks/cc/common.h"
-#include "mediapipe/tasks/cc/components/containers/category.pb.h"
+#include "mediapipe/tasks/cc/components/containers/proto/category.pb.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
 #include "tensorflow/lite/core/shims/cc/shims_test_util.h"
 
 namespace mediapipe {
 namespace tasks {
 namespace audio {
+namespace audio_classifier {
 namespace {
 
 using ::absl::StatusOr;
 using ::mediapipe::file::JoinPath;
+using ::mediapipe::tasks::components::containers::proto::ClassificationResult;
 using ::testing::HasSubstr;
 using ::testing::Optional;
 
@@ -557,6 +559,7 @@ TEST_F(ClassifyAsyncTest, SucceedsWithNonDeterministicNumAudioSamples) {
 }
 
 }  // namespace
+}  // namespace audio_classifier
 }  // namespace audio
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/audio/audio_classifier/proto/BUILD

@@ -19,12 +19,12 @@ package(default_visibility = ["//mediapipe/tasks:internal"])
 licenses(["notice"])
 
 mediapipe_proto_library(
-    name = "audio_classifier_options_proto",
+    name = "audio_classifier_graph_options_proto",
-    srcs = ["audio_classifier_options.proto"],
+    srcs = ["audio_classifier_graph_options.proto"],
     deps = [
         "//mediapipe/framework:calculator_options_proto",
         "//mediapipe/framework:calculator_proto",
-        "//mediapipe/tasks/cc/components/proto:classifier_options_proto",
+        "//mediapipe/tasks/cc/components/processors/proto:classifier_options_proto",
         "//mediapipe/tasks/cc/core/proto:base_options_proto",
     ],
 )

mediapipe/tasks/cc/audio/audio_classifier/proto/audio_classifier_graph_options.proto

@@ -18,12 +18,12 @@ syntax = "proto2";
 package mediapipe.tasks.audio.audio_classifier.proto;
 
 import "mediapipe/framework/calculator.proto";
-import "mediapipe/tasks/cc/components/proto/classifier_options.proto";
+import "mediapipe/tasks/cc/components/processors/proto/classifier_options.proto";
 import "mediapipe/tasks/cc/core/proto/base_options.proto";
 
-message AudioClassifierOptions {
+message AudioClassifierGraphOptions {
   extend mediapipe.CalculatorOptions {
-    optional AudioClassifierOptions ext = 451755788;
+    optional AudioClassifierGraphOptions ext = 451755788;
   }
   // Base options for configuring MediaPipe Tasks, such as specifying the TfLite
   // model file with metadata, accelerator options, etc.
@@ -31,7 +31,7 @@ message AudioClassifierOptions {
 
   // Options for configuring the classifier behavior, such as score threshold,
   // number of results, etc.
-  optional components.proto.ClassifierOptions classifier_options = 2;
+  optional components.processors.proto.ClassifierOptions classifier_options = 2;
 
   // The default sample rate of the input audio. Must be set when the
   // AudioClassifier is configured to process audio stream data.

mediapipe/tasks/cc/components/BUILD

@@ -58,65 +58,6 @@ cc_library(
 
 # TODO: Enable this test
 
-cc_library(
-    name = "classifier_options",
-    srcs = ["classifier_options.cc"],
-    hdrs = ["classifier_options.h"],
-    deps = ["//mediapipe/tasks/cc/components/proto:classifier_options_cc_proto"],
-)
-
-mediapipe_proto_library(
-    name = "classification_postprocessing_options_proto",
-    srcs = ["classification_postprocessing_options.proto"],
-    deps = [
-        "//mediapipe/calculators/tensor:tensors_to_classification_calculator_proto",
-        "//mediapipe/framework:calculator_options_proto",
-        "//mediapipe/framework:calculator_proto",
-        "//mediapipe/tasks/cc/components/calculators:classification_aggregation_calculator_proto",
-        "//mediapipe/tasks/cc/components/calculators:score_calibration_calculator_proto",
-    ],
-)
-
-cc_library(
-    name = "classification_postprocessing",
-    srcs = ["classification_postprocessing.cc"],
-    hdrs = ["classification_postprocessing.h"],
-    deps = [
-        ":classification_postprocessing_options_cc_proto",
-        "//mediapipe/calculators/core:split_vector_calculator",
-        "//mediapipe/calculators/core:split_vector_calculator_cc_proto",
-        "//mediapipe/calculators/tensor:tensors_dequantization_calculator",
-        "//mediapipe/calculators/tensor:tensors_to_classification_calculator",
-        "//mediapipe/calculators/tensor:tensors_to_classification_calculator_cc_proto",
-        "//mediapipe/framework:calculator_framework",
-        "//mediapipe/framework/api2:builder",
-        "//mediapipe/framework/api2:packet",
-        "//mediapipe/framework/api2:port",
-        "//mediapipe/framework/formats:tensor",
-        "//mediapipe/tasks/cc:common",
-        "//mediapipe/tasks/cc/components/calculators:classification_aggregation_calculator",
-        "//mediapipe/tasks/cc/components/calculators:classification_aggregation_calculator_cc_proto",
-        "//mediapipe/tasks/cc/components/calculators:score_calibration_calculator",
-        "//mediapipe/tasks/cc/components/calculators:score_calibration_calculator_cc_proto",
-        "//mediapipe/tasks/cc/components/calculators:score_calibration_utils",
-        "//mediapipe/tasks/cc/components/containers:classifications_cc_proto",
-        "//mediapipe/tasks/cc/components/proto:classifier_options_cc_proto",
-        "//mediapipe/tasks/cc/components/utils:source_or_node_output",
-        "//mediapipe/tasks/cc/core:model_resources",
-        "//mediapipe/tasks/cc/metadata:metadata_extractor",
-        "//mediapipe/tasks/metadata:metadata_schema_cc",
-        "//mediapipe/util:label_map_cc_proto",
-        "//mediapipe/util:label_map_util",
-        "@com_google_absl//absl/container:flat_hash_set",
-        "@com_google_absl//absl/status",
-        "@com_google_absl//absl/status:statusor",
-        "@com_google_absl//absl/strings",
-        "@com_google_absl//absl/strings:str_format",
-        "@org_tensorflow//tensorflow/lite/schema:schema_fbs",
-    ],
-    alwayslink = 1,
-)
-
 cc_library(
     name = "embedder_options",
     srcs = ["embedder_options.cc"],

mediapipe/tasks/cc/components/calculators/BUILD

@@ -37,8 +37,8 @@ cc_library(
         "//mediapipe/framework/api2:packet",
         "//mediapipe/framework/api2:port",
         "//mediapipe/framework/formats:classification_cc_proto",
-        "//mediapipe/tasks/cc/components/containers:category_cc_proto",
+        "//mediapipe/tasks/cc/components/containers/proto:category_cc_proto",
-        "//mediapipe/tasks/cc/components/containers:classifications_cc_proto",
+        "//mediapipe/tasks/cc/components/containers/proto:classifications_cc_proto",
         "@com_google_absl//absl/status",
     ],
     alwayslink = 1,
@@ -128,7 +128,7 @@ cc_library(
         "//mediapipe/framework/port:integral_types",
         "//mediapipe/framework/port:ret_check",
         "//mediapipe/framework/port:status",
-        "//mediapipe/tasks/cc/components/containers:classifications_cc_proto",
+        "//mediapipe/tasks/cc/components/containers/proto:classifications_cc_proto",
     ],
     alwayslink = 1,
 )

mediapipe/tasks/cc/components/calculators/classification_aggregation_calculator.cc

@@ -25,15 +25,15 @@
 #include "mediapipe/framework/calculator_framework.h"
 #include "mediapipe/framework/formats/classification.pb.h"
 #include "mediapipe/tasks/cc/components/calculators/classification_aggregation_calculator.pb.h"
-#include "mediapipe/tasks/cc/components/containers/category.pb.h"
+#include "mediapipe/tasks/cc/components/containers/proto/category.pb.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
 
 namespace mediapipe {
 namespace api2 {
 
 using ::mediapipe::tasks::ClassificationAggregationCalculatorOptions;
-using ::mediapipe::tasks::ClassificationResult;
+using ::mediapipe::tasks::components::containers::proto::ClassificationResult;
-using ::mediapipe::tasks::Classifications;
+using ::mediapipe::tasks::components::containers::proto::Classifications;
 
 // Aggregates ClassificationLists into a single ClassificationResult that has
 // 3 dimensions: (classification head, classification timestamp, classification

mediapipe/tasks/cc/components/calculators/end_loop_calculator.cc

@@ -17,12 +17,13 @@ limitations under the License.
 
 #include <vector>
 
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
 
 // Specialized EndLoopCalculator for Tasks specific types.
 namespace mediapipe::tasks {
 
-typedef EndLoopCalculator<std::vector<ClassificationResult>>
+typedef EndLoopCalculator<
+    std::vector<components::containers::proto::ClassificationResult>>
     EndLoopClassificationResultCalculator;
 REGISTER_CALCULATOR(::mediapipe::tasks::EndLoopClassificationResultCalculator);
 

mediapipe/tasks/cc/components/containers/proto/BUILD

@@ -18,6 +18,24 @@ package(default_visibility = ["//mediapipe/tasks:internal"])
 
 licenses(["notice"])
 
+mediapipe_proto_library(
+    name = "category_proto",
+    srcs = ["category.proto"],
+)
+
+mediapipe_proto_library(
+    name = "classifications_proto",
+    srcs = ["classifications.proto"],
+    deps = [
+        ":category_proto",
+    ],
+)
+
+mediapipe_proto_library(
+    name = "embeddings_proto",
+    srcs = ["embeddings.proto"],
+)
+
 mediapipe_proto_library(
     name = "landmarks_detection_result_proto",
     srcs = [
@@ -29,8 +47,3 @@ mediapipe_proto_library(
         "//mediapipe/framework/formats:rect_proto",
     ],
 )
-
-mediapipe_proto_library(
-    name = "embeddings_proto",
-    srcs = ["embeddings.proto"],
-)

mediapipe/tasks/cc/components/containers/proto/category.proto

@@ -15,7 +15,7 @@ limitations under the License.
 
 syntax = "proto2";
 
-package mediapipe.tasks;
+package mediapipe.tasks.components.containers.proto;
 
 // A single classification result.
 message Category {

mediapipe/tasks/cc/components/containers/proto/classifications.proto

@@ -15,9 +15,9 @@ limitations under the License.
 
 syntax = "proto2";
 
-package mediapipe.tasks;
+package mediapipe.tasks.components.containers.proto;
 
-import "mediapipe/tasks/cc/components/containers/category.proto";
+import "mediapipe/tasks/cc/components/containers/proto/category.proto";
 
 // List of predicted categories with an optional timestamp.
 message ClassificationEntry {

mediapipe/tasks/cc/components/processors/BUILD

@@ -0,0 +1,64 @@
+# Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+package(default_visibility = ["//mediapipe/tasks:internal"])
+
+licenses(["notice"])
+
+cc_library(
+    name = "classifier_options",
+    srcs = ["classifier_options.cc"],
+    hdrs = ["classifier_options.h"],
+    deps = ["//mediapipe/tasks/cc/components/processors/proto:classifier_options_cc_proto"],
+)
+
+cc_library(
+    name = "classification_postprocessing_graph",
+    srcs = ["classification_postprocessing_graph.cc"],
+    hdrs = ["classification_postprocessing_graph.h"],
+    deps = [
+        "//mediapipe/calculators/core:split_vector_calculator",
+        "//mediapipe/calculators/core:split_vector_calculator_cc_proto",
+        "//mediapipe/calculators/tensor:tensors_dequantization_calculator",
+        "//mediapipe/calculators/tensor:tensors_to_classification_calculator",
+        "//mediapipe/calculators/tensor:tensors_to_classification_calculator_cc_proto",
+        "//mediapipe/framework:calculator_framework",
+        "//mediapipe/framework/api2:builder",
+        "//mediapipe/framework/api2:packet",
+        "//mediapipe/framework/api2:port",
+        "//mediapipe/framework/formats:tensor",
+        "//mediapipe/tasks/cc:common",
+        "//mediapipe/tasks/cc/components/calculators:classification_aggregation_calculator",
+        "//mediapipe/tasks/cc/components/calculators:classification_aggregation_calculator_cc_proto",
+        "//mediapipe/tasks/cc/components/calculators:score_calibration_calculator",
+        "//mediapipe/tasks/cc/components/calculators:score_calibration_calculator_cc_proto",
+        "//mediapipe/tasks/cc/components/calculators:score_calibration_utils",
+        "//mediapipe/tasks/cc/components/containers/proto:classifications_cc_proto",
+        "//mediapipe/tasks/cc/components/processors/proto:classification_postprocessing_graph_options_cc_proto",
+        "//mediapipe/tasks/cc/components/processors/proto:classifier_options_cc_proto",
+        "//mediapipe/tasks/cc/components/utils:source_or_node_output",
+        "//mediapipe/tasks/cc/core:model_resources",
+        "//mediapipe/tasks/cc/metadata:metadata_extractor",
+        "//mediapipe/tasks/metadata:metadata_schema_cc",
+        "//mediapipe/util:label_map_cc_proto",
+        "//mediapipe/util:label_map_util",
+        "@com_google_absl//absl/container:flat_hash_set",
+        "@com_google_absl//absl/status",
+        "@com_google_absl//absl/status:statusor",
+        "@com_google_absl//absl/strings",
+        "@com_google_absl//absl/strings:str_format",
+        "@org_tensorflow//tensorflow/lite/schema:schema_fbs",
+    ],
+    alwayslink = 1,
+)

mediapipe/tasks/cc/components/processors/classification_postprocessing_graph.cc

@@ -12,7 +12,7 @@ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 ==============================================================================*/
-#include "mediapipe/tasks/cc/components/classification_postprocessing.h"
+#include "mediapipe/tasks/cc/components/processors/classification_postprocessing_graph.h"
 
 #include <stdint.h>
 
@@ -37,9 +37,9 @@ limitations under the License.
 #include "mediapipe/tasks/cc/components/calculators/classification_aggregation_calculator.pb.h"
 #include "mediapipe/tasks/cc/components/calculators/score_calibration_calculator.pb.h"
 #include "mediapipe/tasks/cc/components/calculators/score_calibration_utils.h"
-#include "mediapipe/tasks/cc/components/classification_postprocessing_options.pb.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classification_postprocessing_graph_options.pb.h"
-#include "mediapipe/tasks/cc/components/proto/classifier_options.pb.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classifier_options.pb.h"
 #include "mediapipe/tasks/cc/components/utils/source_or_node_output.h"
 #include "mediapipe/tasks/cc/core/model_resources.h"
 #include "mediapipe/tasks/cc/metadata/metadata_extractor.h"
@@ -51,6 +51,7 @@ limitations under the License.
 namespace mediapipe {
 namespace tasks {
 namespace components {
+namespace processors {
 
 namespace {
 
@@ -61,7 +62,7 @@ using ::mediapipe::api2::Timestamp;
 using ::mediapipe::api2::builder::GenericNode;
 using ::mediapipe::api2::builder::Graph;
 using ::mediapipe::api2::builder::Source;
-using ::mediapipe::tasks::components::proto::ClassifierOptions;
+using ::mediapipe::tasks::components::containers::proto::ClassificationResult;
 using ::mediapipe::tasks::core::ModelResources;
 using ::mediapipe::tasks::metadata::ModelMetadataExtractor;
 using ::tflite::ProcessUnit;
@@ -79,7 +80,8 @@ constexpr char kTensorsTag[] = "TENSORS";
 constexpr char kTimestampsTag[] = "TIMESTAMPS";
 
 // Performs sanity checks on provided ClassifierOptions.
-absl::Status SanityCheckClassifierOptions(const ClassifierOptions& options) {
+absl::Status SanityCheckClassifierOptions(
+    const proto::ClassifierOptions& options) {
   if (options.max_results() == 0) {
     return CreateStatusWithPayload(
         absl::StatusCode::kInvalidArgument,
@@ -203,7 +205,7 @@ absl::StatusOr<float> GetScoreThreshold(
 
 // Gets the category allowlist or denylist (if any) as a set of indices.
 absl::StatusOr<absl::flat_hash_set<int>> GetAllowOrDenyCategoryIndicesIfAny(
-    const ClassifierOptions& options, const LabelItems& label_items) {
+    const proto::ClassifierOptions& options, const LabelItems& label_items) {
   absl::flat_hash_set<int> category_indices;
   // Exit early if no denylist/allowlist.
   if (options.category_denylist_size() == 0 &&
@@ -239,7 +241,7 @@ absl::StatusOr<absl::flat_hash_set<int>> GetAllowOrDenyCategoryIndicesIfAny(
 
 absl::Status ConfigureScoreCalibrationIfAny(
     const ModelMetadataExtractor& metadata_extractor, int tensor_index,
-    ClassificationPostprocessingOptions* options) {
+    proto::ClassificationPostprocessingGraphOptions* options) {
   const auto* tensor_metadata =
       metadata_extractor.GetOutputTensorMetadata(tensor_index);
   if (tensor_metadata == nullptr) {
@@ -283,7 +285,7 @@ absl::Status ConfigureScoreCalibrationIfAny(
 // Fills in the TensorsToClassificationCalculatorOptions based on the
 // classifier options and the (optional) output tensor metadata.
 absl::Status ConfigureTensorsToClassificationCalculator(
-    const ClassifierOptions& options,
+    const proto::ClassifierOptions& options,
     const ModelMetadataExtractor& metadata_extractor, int tensor_index,
     TensorsToClassificationCalculatorOptions* calculator_options) {
   const auto* tensor_metadata =
@@ -345,10 +347,10 @@ void ConfigureClassificationAggregationCalculator(
 
 }  // namespace
 
-absl::Status ConfigureClassificationPostprocessing(
+absl::Status ConfigureClassificationPostprocessingGraph(
     const ModelResources& model_resources,
-    const ClassifierOptions& classifier_options,
+    const proto::ClassifierOptions& classifier_options,
-    ClassificationPostprocessingOptions* options) {
+    proto::ClassificationPostprocessingGraphOptions* options) {
   MP_RETURN_IF_ERROR(SanityCheckClassifierOptions(classifier_options));
   ASSIGN_OR_RETURN(const auto heads_properties,
                    GetClassificationHeadsProperties(model_resources));
@@ -366,8 +368,8 @@ absl::Status ConfigureClassificationPostprocessing(
   return absl::OkStatus();
 }
 
-// A "mediapipe.tasks.components.ClassificationPostprocessingSubgraph" converts
+// A "ClassificationPostprocessingGraph" converts raw tensors into
-// raw tensors into ClassificationResult objects.
+// ClassificationResult objects.
 // - Accepts CPU input tensors.
 //
 // Inputs:
@@ -381,10 +383,10 @@ absl::Status ConfigureClassificationPostprocessing(
 //   CLASSIFICATION_RESULT - ClassificationResult
 //     The output aggregated classification results.
 //
-// The recommended way of using this subgraph is through the GraphBuilder API
+// The recommended way of using this graph is through the GraphBuilder API
-// using the 'ConfigureClassificationPostprocessing()' function. See header file
+// using the 'ConfigureClassificationPostprocessingGraph()' function. See header
-// for more details.
+// file for more details.
-class ClassificationPostprocessingSubgraph : public mediapipe::Subgraph {
+class ClassificationPostprocessingGraph : public mediapipe::Subgraph {
  public:
   absl::StatusOr<mediapipe::CalculatorGraphConfig> GetConfig(
       mediapipe::SubgraphContext* sc) override {
@@ -392,7 +394,7 @@ class ClassificationPostprocessingSubgraph : public mediapipe::Subgraph {
     ASSIGN_OR_RETURN(
         auto classification_result_out,
         BuildClassificationPostprocessing(
-            sc->Options<ClassificationPostprocessingOptions>(),
+            sc->Options<proto::ClassificationPostprocessingGraphOptions>(),
             graph[Input<std::vector<Tensor>>(kTensorsTag)],
             graph[Input<std::vector<Timestamp>>(kTimestampsTag)], graph));
     classification_result_out >>
@@ -401,19 +403,19 @@ class ClassificationPostprocessingSubgraph : public mediapipe::Subgraph {
   }
 
  private:
-  // Adds an on-device classification postprocessing subgraph into the provided
+  // Adds an on-device classification postprocessing graph into the provided
-  // builder::Graph instance. The classification postprocessing subgraph takes
+  // builder::Graph instance. The classification postprocessing graph takes
   // tensors (std::vector<mediapipe::Tensor>) as input and returns one output
   // stream containing the output classification results (ClassificationResult).
   //
-  // options: the on-device ClassificationPostprocessingOptions.
+  // options: the on-device ClassificationPostprocessingGraphOptions.
   // tensors_in: (std::vector<mediapipe::Tensor>>) tensors to postprocess.
   // timestamps_in: (std::vector<mediapipe::Timestamp>) optional collection of
   //   timestamps that a single ClassificationResult should aggregate.
   // graph: the mediapipe builder::Graph instance to be updated.
   absl::StatusOr<Source<ClassificationResult>>
   BuildClassificationPostprocessing(
-      const ClassificationPostprocessingOptions& options,
+      const proto::ClassificationPostprocessingGraphOptions& options,
       Source<std::vector<Tensor>> tensors_in,
       Source<std::vector<Timestamp>> timestamps_in, Graph& graph) {
     const int num_heads = options.tensors_to_classifications_options_size();
@@ -504,9 +506,11 @@ class ClassificationPostprocessingSubgraph : public mediapipe::Subgraph {
         kClassificationResultTag)];
   }
 };
-REGISTER_MEDIAPIPE_GRAPH(
-    ::mediapipe::tasks::components::ClassificationPostprocessingSubgraph);
 
+REGISTER_MEDIAPIPE_GRAPH(::mediapipe::tasks::components::processors::
+                             ClassificationPostprocessingGraph);  // NOLINT
+
+}  // namespace processors
 }  // namespace components
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/components/processors/classification_postprocessing_graph.h

@@ -13,32 +13,33 @@ See the License for the specific language governing permissions and
 limitations under the License.
 ==============================================================================*/
 
-#ifndef MEDIAPIPE_TASKS_CC_COMPONENTS_CLASSIFICATION_POSTPROCESSING_H_
+#ifndef MEDIAPIPE_TASKS_CC_COMPONENTS_PROCESSORS_CLASSIFICATION_POSTPROCESSING_GRAPH_H_
-#define MEDIAPIPE_TASKS_CC_COMPONENTS_CLASSIFICATION_POSTPROCESSING_H_
+#define MEDIAPIPE_TASKS_CC_COMPONENTS_PROCESSORS_CLASSIFICATION_POSTPROCESSING_GRAPH_H_
 
 #include "absl/status/status.h"
-#include "mediapipe/tasks/cc/components/classification_postprocessing_options.pb.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classification_postprocessing_graph_options.pb.h"
-#include "mediapipe/tasks/cc/components/proto/classifier_options.pb.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classifier_options.pb.h"
 #include "mediapipe/tasks/cc/core/model_resources.h"
 
 namespace mediapipe {
 namespace tasks {
 namespace components {
+namespace processors {
 
-// Configures a ClassificationPostprocessing subgraph using the provided model
+// Configures a ClassificationPostprocessingGraph using the provided model
 // resources and ClassifierOptions.
 // - Accepts CPU input tensors.
 //
 // Example usage:
 //
 //   auto& postprocessing =
-//       graph.AddNode("mediapipe.tasks.components.ClassificationPostprocessingSubgraph");
+//       graph.AddNode("mediapipe.tasks.components.processors.ClassificationPostprocessingGraph");
-//   MP_RETURN_IF_ERROR(ConfigureClassificationPostprocessing(
+//   MP_RETURN_IF_ERROR(ConfigureClassificationPostprocessingGraph(
 //       model_resources,
 //       classifier_options,
-//       &preprocessing.GetOptions<ClassificationPostprocessingOptions>()));
+//       &preprocessing.GetOptions<ClassificationPostprocessingGraphOptions>()));
 //
-// The resulting ClassificationPostprocessing subgraph has the following I/O:
+// The resulting ClassificationPostprocessingGraph has the following I/O:
 // Inputs:
 //   TENSORS - std::vector<Tensor>
 //     The output tensors of an InferenceCalculator.
@@ -49,13 +50,14 @@ namespace components {
 // Outputs:
 //   CLASSIFICATION_RESULT - ClassificationResult
 //     The output aggregated classification results.
-absl::Status ConfigureClassificationPostprocessing(
+absl::Status ConfigureClassificationPostprocessingGraph(
     const tasks::core::ModelResources& model_resources,
-    const tasks::components::proto::ClassifierOptions& classifier_options,
+    const proto::ClassifierOptions& classifier_options,
-    ClassificationPostprocessingOptions* options);
+    proto::ClassificationPostprocessingGraphOptions* options);
 
+}  // namespace processors
 }  // namespace components
 }  // namespace tasks
 }  // namespace mediapipe
 
-#endif  // MEDIAPIPE_TASKS_CC_COMPONENTS_CLASSIFICATION_POSTPROCESSING_H_
+#endif  // MEDIAPIPE_TASKS_CC_COMPONENTS_PROCESSORS_CLASSIFICATION_POSTPROCESSING_GRAPH_H_

mediapipe/tasks/cc/components/processors/classification_postprocessing_graph_test.cc

@@ -13,7 +13,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 ==============================================================================*/
 
-#include "mediapipe/tasks/cc/components/classification_postprocessing.h"
+#include "mediapipe/tasks/cc/components/processors/classification_postprocessing_graph.h"
 
 #include <map>
 #include <memory>
@@ -42,9 +42,9 @@ limitations under the License.
 #include "mediapipe/framework/timestamp.h"
 #include "mediapipe/tasks/cc/components/calculators/classification_aggregation_calculator.pb.h"
 #include "mediapipe/tasks/cc/components/calculators/score_calibration_calculator.pb.h"
-#include "mediapipe/tasks/cc/components/classification_postprocessing_options.pb.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classification_postprocessing_graph_options.pb.h"
-#include "mediapipe/tasks/cc/components/proto/classifier_options.pb.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classifier_options.pb.h"
 #include "mediapipe/tasks/cc/core/model_resources.h"
 #include "mediapipe/tasks/cc/core/proto/external_file.pb.h"
 #include "mediapipe/util/label_map.pb.h"
@@ -53,6 +53,7 @@ limitations under the License.
 namespace mediapipe {
 namespace tasks {
 namespace components {
+namespace processors {
 namespace {
 
 using ::mediapipe::api2::Input;
@@ -60,7 +61,7 @@ using ::mediapipe::api2::Output;
 using ::mediapipe::api2::builder::Graph;
 using ::mediapipe::api2::builder::Source;
 using ::mediapipe::file::JoinPath;
-using ::mediapipe::tasks::components::proto::ClassifierOptions;
+using ::mediapipe::tasks::components::containers::proto::ClassificationResult;
 using ::mediapipe::tasks::core::ModelResources;
 using ::testing::HasSubstr;
 using ::testing::proto::Approximately;
@@ -101,12 +102,12 @@ TEST_F(ConfigureTest, FailsWithInvalidMaxResults) {
   MP_ASSERT_OK_AND_ASSIGN(
       auto model_resources,
       CreateModelResourcesForModel(kQuantizedImageClassifierWithMetadata));
-  ClassifierOptions options_in;
+  proto::ClassifierOptions options_in;
   options_in.set_max_results(0);
 
-  ClassificationPostprocessingOptions options_out;
+  proto::ClassificationPostprocessingGraphOptions options_out;
-  auto status = ConfigureClassificationPostprocessing(*model_resources,
+  auto status = ConfigureClassificationPostprocessingGraph(
-                                                      options_in, &options_out);
+      *model_resources, options_in, &options_out);
 
   EXPECT_EQ(status.code(), absl::StatusCode::kInvalidArgument);
   EXPECT_THAT(status.message(), HasSubstr("Invalid `max_results` option"));
@@ -116,13 +117,13 @@ TEST_F(ConfigureTest, FailsWithBothAllowlistAndDenylist) {
   MP_ASSERT_OK_AND_ASSIGN(
       auto model_resources,
       CreateModelResourcesForModel(kQuantizedImageClassifierWithMetadata));
-  ClassifierOptions options_in;
+  proto::ClassifierOptions options_in;
   options_in.add_category_allowlist("foo");
   options_in.add_category_denylist("bar");
 
-  ClassificationPostprocessingOptions options_out;
+  proto::ClassificationPostprocessingGraphOptions options_out;
-  auto status = ConfigureClassificationPostprocessing(*model_resources,
+  auto status = ConfigureClassificationPostprocessingGraph(
-                                                      options_in, &options_out);
+      *model_resources, options_in, &options_out);
 
   EXPECT_EQ(status.code(), absl::StatusCode::kInvalidArgument);
   EXPECT_THAT(status.message(), HasSubstr("mutually exclusive options"));
@@ -132,12 +133,12 @@ TEST_F(ConfigureTest, FailsWithAllowlistAndNoMetadata) {
   MP_ASSERT_OK_AND_ASSIGN(
       auto model_resources,
       CreateModelResourcesForModel(kQuantizedImageClassifierWithoutMetadata));
-  ClassifierOptions options_in;
+  proto::ClassifierOptions options_in;
   options_in.add_category_allowlist("foo");
 
-  ClassificationPostprocessingOptions options_out;
+  proto::ClassificationPostprocessingGraphOptions options_out;
-  auto status = ConfigureClassificationPostprocessing(*model_resources,
+  auto status = ConfigureClassificationPostprocessingGraph(
-                                                      options_in, &options_out);
+      *model_resources, options_in, &options_out);
 
   EXPECT_EQ(status.code(), absl::StatusCode::kInvalidArgument);
   EXPECT_THAT(
@@ -149,11 +150,11 @@ TEST_F(ConfigureTest, SucceedsWithoutMetadata) {
   MP_ASSERT_OK_AND_ASSIGN(
       auto model_resources,
       CreateModelResourcesForModel(kQuantizedImageClassifierWithoutMetadata));
-  ClassifierOptions options_in;
+  proto::ClassifierOptions options_in;
 
-  ClassificationPostprocessingOptions options_out;
+  proto::ClassificationPostprocessingGraphOptions options_out;
-  MP_ASSERT_OK(ConfigureClassificationPostprocessing(*model_resources,
+  MP_ASSERT_OK(ConfigureClassificationPostprocessingGraph(
-                                                     options_in, &options_out));
+      *model_resources, options_in, &options_out));
 
   EXPECT_THAT(options_out, Approximately(EqualsProto(
                                R"pb(score_calibration_options: []
@@ -171,12 +172,12 @@ TEST_F(ConfigureTest, SucceedsWithMaxResults) {
   MP_ASSERT_OK_AND_ASSIGN(
       auto model_resources,
       CreateModelResourcesForModel(kQuantizedImageClassifierWithoutMetadata));
-  ClassifierOptions options_in;
+  proto::ClassifierOptions options_in;
   options_in.set_max_results(3);
 
-  ClassificationPostprocessingOptions options_out;
+  proto::ClassificationPostprocessingGraphOptions options_out;
-  MP_ASSERT_OK(ConfigureClassificationPostprocessing(*model_resources,
+  MP_ASSERT_OK(ConfigureClassificationPostprocessingGraph(
-                                                     options_in, &options_out));
+      *model_resources, options_in, &options_out));
 
   EXPECT_THAT(options_out, Approximately(EqualsProto(
                                R"pb(score_calibration_options: []
@@ -194,12 +195,12 @@ TEST_F(ConfigureTest, SucceedsWithScoreThreshold) {
   MP_ASSERT_OK_AND_ASSIGN(
       auto model_resources,
       CreateModelResourcesForModel(kQuantizedImageClassifierWithoutMetadata));
-  ClassifierOptions options_in;
+  proto::ClassifierOptions options_in;
   options_in.set_score_threshold(0.5);
 
-  ClassificationPostprocessingOptions options_out;
+  proto::ClassificationPostprocessingGraphOptions options_out;
-  MP_ASSERT_OK(ConfigureClassificationPostprocessing(*model_resources,
+  MP_ASSERT_OK(ConfigureClassificationPostprocessingGraph(
-                                                     options_in, &options_out));
+      *model_resources, options_in, &options_out));
 
   EXPECT_THAT(options_out, Approximately(EqualsProto(
                                R"pb(score_calibration_options: []
@@ -217,11 +218,11 @@ TEST_F(ConfigureTest, SucceedsWithMetadata) {
   MP_ASSERT_OK_AND_ASSIGN(
       auto model_resources,
       CreateModelResourcesForModel(kQuantizedImageClassifierWithMetadata));
-  ClassifierOptions options_in;
+  proto::ClassifierOptions options_in;
 
-  ClassificationPostprocessingOptions options_out;
+  proto::ClassificationPostprocessingGraphOptions options_out;
-  MP_ASSERT_OK(ConfigureClassificationPostprocessing(*model_resources,
+  MP_ASSERT_OK(ConfigureClassificationPostprocessingGraph(
-                                                     options_in, &options_out));
+      *model_resources, options_in, &options_out));
 
   // Check label map size and two first elements.
   EXPECT_EQ(
@@ -254,12 +255,12 @@ TEST_F(ConfigureTest, SucceedsWithAllowlist) {
   MP_ASSERT_OK_AND_ASSIGN(
       auto model_resources,
       CreateModelResourcesForModel(kQuantizedImageClassifierWithMetadata));
-  ClassifierOptions options_in;
+  proto::ClassifierOptions options_in;
   options_in.add_category_allowlist("tench");
 
-  ClassificationPostprocessingOptions options_out;
+  proto::ClassificationPostprocessingGraphOptions options_out;
-  MP_ASSERT_OK(ConfigureClassificationPostprocessing(*model_resources,
+  MP_ASSERT_OK(ConfigureClassificationPostprocessingGraph(
-                                                     options_in, &options_out));
+      *model_resources, options_in, &options_out));
 
   // Clear label map and compare the rest of the options.
   options_out.mutable_tensors_to_classifications_options(0)
@@ -283,12 +284,12 @@ TEST_F(ConfigureTest, SucceedsWithDenylist) {
   MP_ASSERT_OK_AND_ASSIGN(
       auto model_resources,
       CreateModelResourcesForModel(kQuantizedImageClassifierWithMetadata));
-  ClassifierOptions options_in;
+  proto::ClassifierOptions options_in;
   options_in.add_category_denylist("background");
 
-  ClassificationPostprocessingOptions options_out;
+  proto::ClassificationPostprocessingGraphOptions options_out;
-  MP_ASSERT_OK(ConfigureClassificationPostprocessing(*model_resources,
+  MP_ASSERT_OK(ConfigureClassificationPostprocessingGraph(
-                                                     options_in, &options_out));
+      *model_resources, options_in, &options_out));
 
   // Clear label map and compare the rest of the options.
   options_out.mutable_tensors_to_classifications_options(0)
@@ -313,11 +314,11 @@ TEST_F(ConfigureTest, SucceedsWithScoreCalibration) {
       auto model_resources,
       CreateModelResourcesForModel(
           kQuantizedImageClassifierWithDummyScoreCalibration));
-  ClassifierOptions options_in;
+  proto::ClassifierOptions options_in;
 
-  ClassificationPostprocessingOptions options_out;
+  proto::ClassificationPostprocessingGraphOptions options_out;
-  MP_ASSERT_OK(ConfigureClassificationPostprocessing(*model_resources,
+  MP_ASSERT_OK(ConfigureClassificationPostprocessingGraph(
-                                                     options_in, &options_out));
+      *model_resources, options_in, &options_out));
 
   // Check label map size and two first elements.
   EXPECT_EQ(
@@ -362,11 +363,11 @@ TEST_F(ConfigureTest, SucceedsWithMultipleHeads) {
   MP_ASSERT_OK_AND_ASSIGN(
       auto model_resources,
       CreateModelResourcesForModel(kFloatTwoHeadsAudioClassifierWithMetadata));
-  ClassifierOptions options_in;
+  proto::ClassifierOptions options_in;
 
-  ClassificationPostprocessingOptions options_out;
+  proto::ClassificationPostprocessingGraphOptions options_out;
-  MP_ASSERT_OK(ConfigureClassificationPostprocessing(*model_resources,
+  MP_ASSERT_OK(ConfigureClassificationPostprocessingGraph(
-                                                     options_in, &options_out));
+      *model_resources, options_in, &options_out));
   // Check label maps sizes and first two elements.
   EXPECT_EQ(
       options_out.tensors_to_classifications_options(0).label_items_size(),
@@ -414,17 +415,19 @@ TEST_F(ConfigureTest, SucceedsWithMultipleHeads) {
 class PostprocessingTest : public tflite_shims::testing::Test {
  protected:
   absl::StatusOr<OutputStreamPoller> BuildGraph(
-      absl::string_view model_name, const ClassifierOptions& options,
+      absl::string_view model_name, const proto::ClassifierOptions& options,
       bool connect_timestamps = false) {
     ASSIGN_OR_RETURN(auto model_resources,
                      CreateModelResourcesForModel(model_name));
 
     Graph graph;
     auto& postprocessing = graph.AddNode(
-        "mediapipe.tasks.components.ClassificationPostprocessingSubgraph");
+        "mediapipe.tasks.components.processors."
-    MP_RETURN_IF_ERROR(ConfigureClassificationPostprocessing(
+        "ClassificationPostprocessingGraph");
+    MP_RETURN_IF_ERROR(ConfigureClassificationPostprocessingGraph(
         *model_resources, options,
-        &postprocessing.GetOptions<ClassificationPostprocessingOptions>()));
+        &postprocessing
+             .GetOptions<proto::ClassificationPostprocessingGraphOptions>()));
     graph[Input<std::vector<Tensor>>(kTensorsTag)].SetName(kTensorsName) >>
         postprocessing.In(kTensorsTag);
     if (connect_timestamps) {
@@ -495,7 +498,7 @@ class PostprocessingTest : public tflite_shims::testing::Test {
 
 TEST_F(PostprocessingTest, SucceedsWithoutMetadata) {
   // Build graph.
-  ClassifierOptions options;
+  proto::ClassifierOptions options;
   options.set_max_results(3);
   options.set_score_threshold(0.5);
   MP_ASSERT_OK_AND_ASSIGN(
@@ -524,7 +527,7 @@ TEST_F(PostprocessingTest, SucceedsWithoutMetadata) {
 
 TEST_F(PostprocessingTest, SucceedsWithMetadata) {
   // Build graph.
-  ClassifierOptions options;
+  proto::ClassifierOptions options;
   options.set_max_results(3);
   MP_ASSERT_OK_AND_ASSIGN(
       auto poller, BuildGraph(kQuantizedImageClassifierWithMetadata, options));
@@ -567,7 +570,7 @@ TEST_F(PostprocessingTest, SucceedsWithMetadata) {
 
 TEST_F(PostprocessingTest, SucceedsWithScoreCalibration) {
   // Build graph.
-  ClassifierOptions options;
+  proto::ClassifierOptions options;
   options.set_max_results(3);
   MP_ASSERT_OK_AND_ASSIGN(
       auto poller,
@@ -613,7 +616,7 @@ TEST_F(PostprocessingTest, SucceedsWithScoreCalibration) {
 
 TEST_F(PostprocessingTest, SucceedsWithMultipleHeads) {
   // Build graph.
-  ClassifierOptions options;
+  proto::ClassifierOptions options;
   options.set_max_results(2);
   MP_ASSERT_OK_AND_ASSIGN(
       auto poller,
@@ -673,7 +676,7 @@ TEST_F(PostprocessingTest, SucceedsWithMultipleHeads) {
 
 TEST_F(PostprocessingTest, SucceedsWithTimestamps) {
   // Build graph.
-  ClassifierOptions options;
+  proto::ClassifierOptions options;
   options.set_max_results(2);
   MP_ASSERT_OK_AND_ASSIGN(
       auto poller, BuildGraph(kQuantizedImageClassifierWithMetadata, options,
@@ -729,6 +732,7 @@ TEST_F(PostprocessingTest, SucceedsWithTimestamps) {
 }
 
 }  // namespace
+}  // namespace processors
 }  // namespace components
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/components/processors/classifier_options.cc

@@ -13,17 +13,18 @@ See the License for the specific language governing permissions and
 limitations under the License.
 ==============================================================================*/
 
-#include "mediapipe/tasks/cc/components/classifier_options.h"
+#include "mediapipe/tasks/cc/components/processors/classifier_options.h"
 
-#include "mediapipe/tasks/cc/components/proto/classifier_options.pb.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classifier_options.pb.h"
 
 namespace mediapipe {
 namespace tasks {
 namespace components {
+namespace processors {
 
-tasks::components::proto::ClassifierOptions ConvertClassifierOptionsToProto(
+proto::ClassifierOptions ConvertClassifierOptionsToProto(
     ClassifierOptions* options) {
-  tasks::components::proto::ClassifierOptions options_proto;
+  proto::ClassifierOptions options_proto;
   options_proto.set_display_names_locale(options->display_names_locale);
   options_proto.set_max_results(options->max_results);
   options_proto.set_score_threshold(options->score_threshold);
@@ -36,6 +37,7 @@ tasks::components::proto::ClassifierOptions ConvertClassifierOptionsToProto(
   return options_proto;
 }
 
+}  // namespace processors
 }  // namespace components
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/components/processors/classifier_options.h

@@ -13,14 +13,15 @@ See the License for the specific language governing permissions and
 limitations under the License.
 ==============================================================================*/
 
-#ifndef MEDIAPIPE_TASKS_CC_COMPONENTS_CLASSIFIER_OPTIONS_H_
+#ifndef MEDIAPIPE_TASKS_CC_COMPONENTS_PROCESSORS_CLASSIFIER_OPTIONS_H_
-#define MEDIAPIPE_TASKS_CC_COMPONENTS_CLASSIFIER_OPTIONS_H_
+#define MEDIAPIPE_TASKS_CC_COMPONENTS_PROCESSORS_CLASSIFIER_OPTIONS_H_
 
-#include "mediapipe/tasks/cc/components/proto/classifier_options.pb.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classifier_options.pb.h"
 
 namespace mediapipe {
 namespace tasks {
 namespace components {
+namespace processors {
 
 // Classifier options for MediaPipe C++ classification Tasks.
 struct ClassifierOptions {
@@ -49,11 +50,12 @@ struct ClassifierOptions {
 };
 
 // Converts a ClassifierOptions to a ClassifierOptionsProto.
-tasks::components::proto::ClassifierOptions ConvertClassifierOptionsToProto(
+proto::ClassifierOptions ConvertClassifierOptionsToProto(
     ClassifierOptions* classifier_options);
 
+}  // namespace processors
 }  // namespace components
 }  // namespace tasks
 }  // namespace mediapipe
 
-#endif  // MEDIAPIPE_TASKS_CC_COMPONENTS_CLASSIFIER_OPTIONS_H_
+#endif  // MEDIAPIPE_TASKS_CC_COMPONENTS_PROCESSORS_CLASSIFIER_OPTIONS_H_

mediapipe/tasks/cc/components/processors/proto/BUILD

@@ -19,14 +19,18 @@ package(default_visibility = ["//mediapipe/tasks:internal"])
 licenses(["notice"])
 
 mediapipe_proto_library(
-    name = "category_proto",
+    name = "classifier_options_proto",
-    srcs = ["category.proto"],
+    srcs = ["classifier_options.proto"],
 )
 
 mediapipe_proto_library(
-    name = "classifications_proto",
+    name = "classification_postprocessing_graph_options_proto",
-    srcs = ["classifications.proto"],
+    srcs = ["classification_postprocessing_graph_options.proto"],
     deps = [
-        ":category_proto",
+        "//mediapipe/calculators/tensor:tensors_to_classification_calculator_proto",
+        "//mediapipe/framework:calculator_options_proto",
+        "//mediapipe/framework:calculator_proto",
+        "//mediapipe/tasks/cc/components/calculators:classification_aggregation_calculator_proto",
+        "//mediapipe/tasks/cc/components/calculators:score_calibration_calculator_proto",
     ],
 )

mediapipe/tasks/cc/components/processors/proto/classification_postprocessing_graph_options.proto

@@ -15,16 +15,16 @@ limitations under the License.
 
 syntax = "proto2";
 
-package mediapipe.tasks.components;
+package mediapipe.tasks.components.processors.proto;
 
 import "mediapipe/calculators/tensor/tensors_to_classification_calculator.proto";
 import "mediapipe/framework/calculator.proto";
 import "mediapipe/tasks/cc/components/calculators/classification_aggregation_calculator.proto";
 import "mediapipe/tasks/cc/components/calculators/score_calibration_calculator.proto";
 
-message ClassificationPostprocessingOptions {
+message ClassificationPostprocessingGraphOptions {
   extend mediapipe.CalculatorOptions {
-    optional ClassificationPostprocessingOptions ext = 460416950;
+    optional ClassificationPostprocessingGraphOptions ext = 460416950;
   }
 
   // Optional mapping between output tensor index and corresponding score

mediapipe/tasks/cc/components/processors/proto/classifier_options.proto

@@ -15,7 +15,7 @@ limitations under the License.
 
 syntax = "proto2";
 
-package mediapipe.tasks.components.proto;
+package mediapipe.tasks.components.processors.proto;
 
 // Shared options used by all classification tasks.
 message ClassifierOptions {

mediapipe/tasks/cc/components/proto/BUILD

@@ -23,11 +23,6 @@ mediapipe_proto_library(
     srcs = ["segmenter_options.proto"],
 )
 
-mediapipe_proto_library(
-    name = "classifier_options_proto",
-    srcs = ["classifier_options.proto"],
-)
-
 mediapipe_proto_library(
     name = "embedder_options_proto",
     srcs = ["embedder_options.proto"],

mediapipe/tasks/cc/components/utils/BUILD

@@ -42,3 +42,16 @@ cc_test(
         "//mediapipe/tasks/cc/components/containers/proto:embeddings_cc_proto",
     ],
 )
+
+cc_library(
+    name = "gate",
+    hdrs = ["gate.h"],
+    deps = [
+        "//mediapipe/calculators/core:gate_calculator",
+        "//mediapipe/calculators/core:gate_calculator_cc_proto",
+        "//mediapipe/framework/api2:builder",
+        "//mediapipe/framework/api2:port",
+    ],
+)
+
+# TODO: Enable this test

mediapipe/tasks/cc/components/utils/gate.h

@@ -0,0 +1,160 @@
+/* Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+==============================================================================*/
+
+#ifndef MEDIAPIPE_TASKS_CC_COMPONENTS_UTILS_GATE_H_
+#define MEDIAPIPE_TASKS_CC_COMPONENTS_UTILS_GATE_H_
+
+#include <utility>
+
+#include "mediapipe/calculators/core/gate_calculator.pb.h"
+#include "mediapipe/framework/api2/builder.h"
+
+namespace mediapipe {
+namespace tasks {
+namespace components {
+namespace utils {
+
+// Utility class that simplifies allowing (gating) multiple streams.
+class AllowGate {
+ public:
+  AllowGate(api2::builder::Source<bool> allow, api2::builder::Graph& graph)
+      : node_(AddSourceGate(allow, graph)) {}
+  AllowGate(api2::builder::SideSource<bool> allow, api2::builder::Graph& graph)
+      : node_(AddSideSourceGate(allow, graph)) {}
+
+  // Move-only
+  AllowGate(AllowGate&& allow_gate) = default;
+  AllowGate& operator=(AllowGate&& allow_gate) = default;
+
+  template <typename T>
+  api2::builder::Source<T> Allow(api2::builder::Source<T> source) {
+    source >> node_.In(index_);
+    return node_.Out(index_++).Cast<T>();
+  }
+
+ private:
+  template <typename T>
+  static api2::builder::GenericNode& AddSourceGate(
+      T allow, api2::builder::Graph& graph) {
+    auto& gate_node = graph.AddNode("GateCalculator");
+    allow >> gate_node.In("ALLOW");
+    return gate_node;
+  }
+
+  template <typename T>
+  static api2::builder::GenericNode& AddSideSourceGate(
+      T allow, api2::builder::Graph& graph) {
+    auto& gate_node = graph.AddNode("GateCalculator");
+    allow >> gate_node.SideIn("ALLOW");
+    return gate_node;
+  }
+
+  api2::builder::GenericNode& node_;
+  int index_ = 0;
+};
+
+// Utility class that simplifies disallowing (gating) multiple streams.
+class DisallowGate {
+ public:
+  DisallowGate(api2::builder::Source<bool> disallow,
+               api2::builder::Graph& graph)
+      : node_(AddSourceGate(disallow, graph)) {}
+  DisallowGate(api2::builder::SideSource<bool> disallow,
+               api2::builder::Graph& graph)
+      : node_(AddSideSourceGate(disallow, graph)) {}
+
+  // Move-only
+  DisallowGate(DisallowGate&& disallow_gate) = default;
+  DisallowGate& operator=(DisallowGate&& disallow_gate) = default;
+
+  template <typename T>
+  api2::builder::Source<T> Disallow(api2::builder::Source<T> source) {
+    source >> node_.In(index_);
+    return node_.Out(index_++).Cast<T>();
+  }
+
+ private:
+  template <typename T>
+  static api2::builder::GenericNode& AddSourceGate(
+      T disallow, api2::builder::Graph& graph) {
+    auto& gate_node = graph.AddNode("GateCalculator");
+    auto& gate_node_opts =
+        gate_node.GetOptions<mediapipe::GateCalculatorOptions>();
+    // Supposedly, the most popular configuration for MediaPipe Tasks team
+    // graphs. Hence, intentionally hard coded to catch and verify any other use
+    // case (should help to workout a common approach and have a recommended way
+    // of blocking streams).
+    gate_node_opts.set_empty_packets_as_allow(true);
+    disallow >> gate_node.In("DISALLOW");
+    return gate_node;
+  }
+
+  template <typename T>
+  static api2::builder::GenericNode& AddSideSourceGate(
+      T disallow, api2::builder::Graph& graph) {
+    auto& gate_node = graph.AddNode("GateCalculator");
+    auto& gate_node_opts =
+        gate_node.GetOptions<mediapipe::GateCalculatorOptions>();
+    gate_node_opts.set_empty_packets_as_allow(true);
+    disallow >> gate_node.SideIn("DISALLOW");
+    return gate_node;
+  }
+
+  api2::builder::GenericNode& node_;
+  int index_ = 0;
+};
+
+// Updates graph to drop @value stream packet if corresponding @condition stream
+// packet holds true.
+template <class T>
+api2::builder::Source<T> DisallowIf(api2::builder::Source<T> value,
+                                    api2::builder::Source<bool> condition,
+                                    api2::builder::Graph& graph) {
+  return DisallowGate(condition, graph).Disallow(value);
+}
+
+// Updates graph to drop @value stream packet if corresponding @condition stream
+// packet holds true.
+template <class T>
+api2::builder::Source<T> DisallowIf(api2::builder::Source<T> value,
+                                    api2::builder::SideSource<bool> condition,
+                                    api2::builder::Graph& graph) {
+  return DisallowGate(condition, graph).Disallow(value);
+}
+
+// Updates graph to pass through @value stream packet if corresponding
+// @allow stream packet holds true.
+template <class T>
+api2::builder::Source<T> AllowIf(api2::builder::Source<T> value,
+                                 api2::builder::Source<bool> allow,
+                                 api2::builder::Graph& graph) {
+  return AllowGate(allow, graph).Allow(value);
+}
+
+// Updates graph to pass through @value stream packet if corresponding
+// @allow side stream packet holds true.
+template <class T>
+api2::builder::Source<T> AllowIf(api2::builder::Source<T> value,
+                                 api2::builder::SideSource<bool> allow,
+                                 api2::builder::Graph& graph) {
+  return AllowGate(allow, graph).Allow(value);
+}
+
+}  // namespace utils
+}  // namespace components
+}  // namespace tasks
+}  // namespace mediapipe
+
+#endif  // MEDIAPIPE_TASKS_CC_COMPONENTS_UTILS_GATE_H_

mediapipe/tasks/cc/components/utils/gate_test.cc

@@ -0,0 +1,229 @@
+/* Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+==============================================================================*/
+
+#include "mediapipe/tasks/cc/components/utils/gate.h"
+
+#include "mediapipe/framework/api2/builder.h"
+#include "mediapipe/framework/calculator_framework.h"
+#include "mediapipe/framework/calculator_graph.h"
+#include "mediapipe/framework/port/gmock.h"
+#include "mediapipe/framework/port/gtest.h"
+#include "mediapipe/framework/port/parse_text_proto.h"
+
+namespace mediapipe {
+namespace tasks {
+namespace components {
+namespace utils {
+namespace {
+
+using ::mediapipe::api2::builder::SideSource;
+using ::mediapipe::api2::builder::Source;
+
+TEST(DisallowGate, VerifyConfig) {
+  mediapipe::api2::builder::Graph graph;
+
+  Source<bool> condition = graph.In("CONDITION").Cast<bool>();
+  Source<int> value1 = graph.In("VALUE_1").Cast<int>();
+  Source<int> value2 = graph.In("VALUE_2").Cast<int>();
+  Source<int> value3 = graph.In("VALUE_3").Cast<int>();
+
+  DisallowGate gate(condition, graph);
+  gate.Disallow(value1).SetName("gated_stream1");
+  gate.Disallow(value2).SetName("gated_stream2");
+  gate.Disallow(value3).SetName("gated_stream3");
+
+  EXPECT_THAT(graph.GetConfig(),
+              testing::EqualsProto(
+                  mediapipe::ParseTextProtoOrDie<CalculatorGraphConfig>(R"pb(
+                    node {
+                      calculator: "GateCalculator"
+                      input_stream: "__stream_1"
+                      input_stream: "__stream_2"
+                      input_stream: "__stream_3"
+                      input_stream: "DISALLOW:__stream_0"
+                      output_stream: "gated_stream1"
+                      output_stream: "gated_stream2"
+                      output_stream: "gated_stream3"
+                      options {
+                        [mediapipe.GateCalculatorOptions.ext] {
+                          empty_packets_as_allow: true
+                        }
+                      }
+                    }
+                    input_stream: "CONDITION:__stream_0"
+                    input_stream: "VALUE_1:__stream_1"
+                    input_stream: "VALUE_2:__stream_2"
+                    input_stream: "VALUE_3:__stream_3"
+                  )pb")));
+
+  CalculatorGraph calcualtor_graph;
+  MP_EXPECT_OK(calcualtor_graph.Initialize(graph.GetConfig()));
+}
+
+TEST(DisallowIf, VerifyConfig) {
+  mediapipe::api2::builder::Graph graph;
+
+  Source<int> value = graph.In("VALUE").Cast<int>();
+  Source<bool> condition = graph.In("CONDITION").Cast<bool>();
+
+  auto gated_stream = DisallowIf(value, condition, graph);
+  gated_stream.SetName("gated_stream");
+
+  EXPECT_THAT(graph.GetConfig(),
+              testing::EqualsProto(
+                  mediapipe::ParseTextProtoOrDie<CalculatorGraphConfig>(R"pb(
+                    node {
+                      calculator: "GateCalculator"
+                      input_stream: "__stream_1"
+                      input_stream: "DISALLOW:__stream_0"
+                      output_stream: "gated_stream"
+                      options {
+                        [mediapipe.GateCalculatorOptions.ext] {
+                          empty_packets_as_allow: true
+                        }
+                      }
+                    }
+                    input_stream: "CONDITION:__stream_0"
+                    input_stream: "VALUE:__stream_1"
+                  )pb")));
+
+  CalculatorGraph calcualtor_graph;
+  MP_EXPECT_OK(calcualtor_graph.Initialize(graph.GetConfig()));
+}
+
+TEST(DisallowIf, VerifyConfigWithSideCondition) {
+  mediapipe::api2::builder::Graph graph;
+
+  Source<int> value = graph.In("VALUE").Cast<int>();
+  SideSource<bool> condition = graph.SideIn("CONDITION").Cast<bool>();
+
+  auto gated_stream = DisallowIf(value, condition, graph);
+  gated_stream.SetName("gated_stream");
+
+  EXPECT_THAT(graph.GetConfig(),
+              testing::EqualsProto(
+                  mediapipe::ParseTextProtoOrDie<CalculatorGraphConfig>(R"pb(
+                    node {
+                      calculator: "GateCalculator"
+                      input_stream: "__stream_0"
+                      output_stream: "gated_stream"
+                      input_side_packet: "DISALLOW:__side_packet_1"
+                      options {
+                        [mediapipe.GateCalculatorOptions.ext] {
+                          empty_packets_as_allow: true
+                        }
+                      }
+                    }
+                    input_stream: "VALUE:__stream_0"
+                    input_side_packet: "CONDITION:__side_packet_1"
+                  )pb")));
+
+  CalculatorGraph calcualtor_graph;
+  MP_EXPECT_OK(calcualtor_graph.Initialize(graph.GetConfig()));
+}
+
+TEST(AllowGate, VerifyConfig) {
+  mediapipe::api2::builder::Graph graph;
+
+  Source<bool> condition = graph.In("CONDITION").Cast<bool>();
+  Source<int> value1 = graph.In("VALUE_1").Cast<int>();
+  Source<int> value2 = graph.In("VALUE_2").Cast<int>();
+  Source<int> value3 = graph.In("VALUE_3").Cast<int>();
+
+  AllowGate gate(condition, graph);
+  gate.Allow(value1).SetName("gated_stream1");
+  gate.Allow(value2).SetName("gated_stream2");
+  gate.Allow(value3).SetName("gated_stream3");
+
+  EXPECT_THAT(graph.GetConfig(),
+              testing::EqualsProto(
+                  mediapipe::ParseTextProtoOrDie<CalculatorGraphConfig>(R"pb(
+                    node {
+                      calculator: "GateCalculator"
+                      input_stream: "__stream_1"
+                      input_stream: "__stream_2"
+                      input_stream: "__stream_3"
+                      input_stream: "ALLOW:__stream_0"
+                      output_stream: "gated_stream1"
+                      output_stream: "gated_stream2"
+                      output_stream: "gated_stream3"
+                    }
+                    input_stream: "CONDITION:__stream_0"
+                    input_stream: "VALUE_1:__stream_1"
+                    input_stream: "VALUE_2:__stream_2"
+                    input_stream: "VALUE_3:__stream_3"
+                  )pb")));
+
+  CalculatorGraph calcualtor_graph;
+  MP_EXPECT_OK(calcualtor_graph.Initialize(graph.GetConfig()));
+}
+
+TEST(AllowIf, VerifyConfig) {
+  mediapipe::api2::builder::Graph graph;
+
+  Source<int> value = graph.In("VALUE").Cast<int>();
+  Source<bool> condition = graph.In("CONDITION").Cast<bool>();
+
+  auto gated_stream = AllowIf(value, condition, graph);
+  gated_stream.SetName("gated_stream");
+
+  EXPECT_THAT(graph.GetConfig(),
+              testing::EqualsProto(
+                  mediapipe::ParseTextProtoOrDie<CalculatorGraphConfig>(R"pb(
+                    node {
+                      calculator: "GateCalculator"
+                      input_stream: "__stream_1"
+                      input_stream: "ALLOW:__stream_0"
+                      output_stream: "gated_stream"
+                    }
+                    input_stream: "CONDITION:__stream_0"
+                    input_stream: "VALUE:__stream_1"
+                  )pb")));
+
+  CalculatorGraph calcualtor_graph;
+  MP_EXPECT_OK(calcualtor_graph.Initialize(graph.GetConfig()));
+}
+
+TEST(AllowIf, VerifyConfigWithSideConition) {
+  mediapipe::api2::builder::Graph graph;
+
+  Source<int> value = graph.In("VALUE").Cast<int>();
+  SideSource<bool> condition = graph.SideIn("CONDITION").Cast<bool>();
+
+  auto gated_stream = AllowIf(value, condition, graph);
+  gated_stream.SetName("gated_stream");
+
+  EXPECT_THAT(graph.GetConfig(),
+              testing::EqualsProto(
+                  mediapipe::ParseTextProtoOrDie<CalculatorGraphConfig>(R"pb(
+                    node {
+                      calculator: "GateCalculator"
+                      input_stream: "__stream_0"
+                      output_stream: "gated_stream"
+                      input_side_packet: "ALLOW:__side_packet_1"
+                    }
+                    input_stream: "VALUE:__stream_0"
+                    input_side_packet: "CONDITION:__side_packet_1"
+                  )pb")));
+
+  CalculatorGraph calcualtor_graph;
+  MP_EXPECT_OK(calcualtor_graph.Initialize(graph.GetConfig()));
+}
+
+}  // namespace
+}  // namespace utils
+}  // namespace components
+}  // namespace tasks
+}  // namespace mediapipe

mediapipe/tasks/cc/core/BUILD

@@ -23,6 +23,7 @@ cc_library(
     srcs = ["base_options.cc"],
     hdrs = ["base_options.h"],
     deps = [
+        ":mediapipe_builtin_op_resolver",
         "//mediapipe/calculators/tensor:inference_calculator_cc_proto",
         "//mediapipe/tasks/cc/core/proto:acceleration_cc_proto",
         "//mediapipe/tasks/cc/core/proto:base_options_cc_proto",
@@ -50,6 +51,21 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "mediapipe_builtin_op_resolver",
+    srcs = ["mediapipe_builtin_op_resolver.cc"],
+    hdrs = ["mediapipe_builtin_op_resolver.h"],
+    deps = [
+        "//mediapipe/util/tflite/operations:landmarks_to_transform_matrix",
+        "//mediapipe/util/tflite/operations:max_pool_argmax",
+        "//mediapipe/util/tflite/operations:max_unpooling",
+        "//mediapipe/util/tflite/operations:transform_landmarks",
+        "//mediapipe/util/tflite/operations:transform_tensor_bilinear",
+        "//mediapipe/util/tflite/operations:transpose_conv_bias",
+        "@org_tensorflow//tensorflow/lite/kernels:builtin_ops",
+    ],
+)
+
 # TODO: Switch to use cc_library_with_tflite after the MediaPipe InferenceCalculator
 # supports TFLite-in-GMSCore.
 cc_library(

mediapipe/tasks/cc/core/base_options.h

@@ -20,6 +20,7 @@ limitations under the License.
 #include <string>
 
 #include "absl/memory/memory.h"
+#include "mediapipe/tasks/cc/core/mediapipe_builtin_op_resolver.h"
 #include "mediapipe/tasks/cc/core/proto/base_options.pb.h"
 #include "tensorflow/lite/core/api/op_resolver.h"
 #include "tensorflow/lite/kernels/register.h"
@@ -63,7 +64,7 @@ struct BaseOptions {
   // A non-default OpResolver to support custom Ops or specify a subset of
   // built-in Ops.
   std::unique_ptr<tflite::OpResolver> op_resolver =
-      absl::make_unique<tflite::ops::builtin::BuiltinOpResolver>();
+      absl::make_unique<MediaPipeBuiltinOpResolver>();
 };
 
 // Converts a BaseOptions to a BaseOptionsProto.

mediapipe/tasks/cc/core/mediapipe_builtin_op_resolver.cc

@@ -13,7 +13,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 ==============================================================================*/
 
-#include "mediapipe/tasks/cc/vision/image_segmenter/image_segmenter_op_resolvers.h"
+#include "mediapipe/tasks/cc/core/mediapipe_builtin_op_resolver.h"
 
 #include "mediapipe/util/tflite/operations/landmarks_to_transform_matrix.h"
 #include "mediapipe/util/tflite/operations/max_pool_argmax.h"
@@ -21,14 +21,11 @@ limitations under the License.
 #include "mediapipe/util/tflite/operations/transform_landmarks.h"
 #include "mediapipe/util/tflite/operations/transform_tensor_bilinear.h"
 #include "mediapipe/util/tflite/operations/transpose_conv_bias.h"
-#include "tensorflow/lite/kernels/register.h"
 
 namespace mediapipe {
 namespace tasks {
-namespace vision {
+namespace core {
-
+MediaPipeBuiltinOpResolver::MediaPipeBuiltinOpResolver() {
-SelfieSegmentationModelOpResolver::SelfieSegmentationModelOpResolver()
-    : BuiltinOpResolver() {
   AddCustom("MaxPoolingWithArgmax2D",
             mediapipe::tflite_operations::RegisterMaxPoolingWithArgmax2D());
   AddCustom("MaxUnpooling2D",
@@ -46,7 +43,6 @@ SelfieSegmentationModelOpResolver::SelfieSegmentationModelOpResolver()
       mediapipe::tflite_operations::RegisterLandmarksToTransformMatrixV2(),
       /*version=*/2);
 }
-
+}  // namespace core
-}  // namespace vision
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/core/mediapipe_builtin_op_resolver.h

@@ -13,25 +13,23 @@ See the License for the specific language governing permissions and
 limitations under the License.
 ==============================================================================*/
 
-#ifndef MEDIAPIPE_TASKS_CC_VISION_IMAGE_SEGMENTER_IMAGE_SEGMENTER_OP_RESOLVERS_H_
+#ifndef MEDIAPIPE_TASKS_CC_CORE_MEDIAPIPE_BUILTIN_OP_RESOLVER_H_
-#define MEDIAPIPE_TASKS_CC_VISION_IMAGE_SEGMENTER_IMAGE_SEGMENTER_OP_RESOLVERS_H_
+#define MEDIAPIPE_TASKS_CC_CORE_MEDIAPIPE_BUILTIN_OP_RESOLVER_H_
 
 #include "tensorflow/lite/kernels/register.h"
 
 namespace mediapipe {
 namespace tasks {
-namespace vision {
+namespace core {
-
+class MediaPipeBuiltinOpResolver
-class SelfieSegmentationModelOpResolver
     : public tflite::ops::builtin::BuiltinOpResolver {
  public:
-  SelfieSegmentationModelOpResolver();
+  MediaPipeBuiltinOpResolver();
-  SelfieSegmentationModelOpResolver(
+  MediaPipeBuiltinOpResolver(const MediaPipeBuiltinOpResolver& r) = delete;
-      const SelfieSegmentationModelOpResolver& r) = delete;
 };
 
-}  // namespace vision
+}  // namespace core
 }  // namespace tasks
 }  // namespace mediapipe
 
-#endif  // MEDIAPIPE_TASKS_CC_VISION_IMAGE_SEGMENTER_IMAGE_SEGMENTER_OP_RESOLVERS_H_
+#endif  // MEDIAPIPE_TASKS_CC_CORE_MEDIAPIPE_BUILTIN_OP_RESOLVER_H_

mediapipe/tasks/cc/vision/hand_detector/BUILD

@@ -18,18 +18,6 @@ package(default_visibility = [
 
 licenses(["notice"])
 
-cc_library(
-    name = "hand_detector_op_resolver",
-    srcs = ["hand_detector_op_resolver.cc"],
-    hdrs = ["hand_detector_op_resolver.h"],
-    deps = [
-        "//mediapipe/util/tflite/operations:max_pool_argmax",
-        "//mediapipe/util/tflite/operations:max_unpooling",
-        "//mediapipe/util/tflite/operations:transpose_conv_bias",
-        "@org_tensorflow//tensorflow/lite/kernels:builtin_ops",
-    ],
-)
-
 cc_library(
     name = "hand_detector_graph",
     srcs = ["hand_detector_graph.cc"],

mediapipe/tasks/cc/vision/hand_detector/hand_detector_graph_test.cc

@@ -35,11 +35,11 @@ limitations under the License.
 #include "mediapipe/framework/port/gmock.h"
 #include "mediapipe/framework/port/gtest.h"
 #include "mediapipe/framework/port/parse_text_proto.h"
+#include "mediapipe/tasks/cc/core/mediapipe_builtin_op_resolver.h"
 #include "mediapipe/tasks/cc/core/model_resources.h"
 #include "mediapipe/tasks/cc/core/proto/base_options.pb.h"
 #include "mediapipe/tasks/cc/core/proto/external_file.pb.h"
 #include "mediapipe/tasks/cc/core/task_runner.h"
-#include "mediapipe/tasks/cc/vision/hand_detector/hand_detector_op_resolver.h"
 #include "mediapipe/tasks/cc/vision/hand_detector/proto/hand_detector_options.pb.h"
 #include "mediapipe/tasks/cc/vision/hand_detector/proto/hand_detector_result.pb.h"
 #include "mediapipe/tasks/cc/vision/utils/image_utils.h"
@@ -121,8 +121,8 @@ absl::StatusOr<std::unique_ptr<TaskRunner>> CreateTaskRunner(
   hand_detection.Out(kHandNormRectsTag).SetName(kHandNormRectsName) >>
       graph[Output<std::vector<NormalizedRect>>(kHandNormRectsTag)];
 
-  return TaskRunner::Create(graph.GetConfig(),
+  return TaskRunner::Create(
-                            absl::make_unique<HandDetectorOpResolver>());
+      graph.GetConfig(), std::make_unique<core::MediaPipeBuiltinOpResolver>());
 }
 
 HandDetectorResult GetExpectedHandDetectorResult(absl::string_view file_name) {

mediapipe/tasks/cc/vision/hand_detector/hand_detector_op_resolver.cc

@@ -1,35 +0,0 @@
-/* Copyright 2022 The MediaPipe Authors. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-==============================================================================*/
-
-#include "mediapipe/tasks/cc/vision/hand_detector/hand_detector_op_resolver.h"
-
-#include "mediapipe/util/tflite/operations/max_pool_argmax.h"
-#include "mediapipe/util/tflite/operations/max_unpooling.h"
-#include "mediapipe/util/tflite/operations/transpose_conv_bias.h"
-
-namespace mediapipe {
-namespace tasks {
-namespace vision {
-HandDetectorOpResolver::HandDetectorOpResolver() {
-  AddCustom("MaxPoolingWithArgmax2D",
-            mediapipe::tflite_operations::RegisterMaxPoolingWithArgmax2D());
-  AddCustom("MaxUnpooling2D",
-            mediapipe::tflite_operations::RegisterMaxUnpooling2D());
-  AddCustom("Convolution2DTransposeBias",
-            mediapipe::tflite_operations::RegisterConvolution2DTransposeBias());
-}
-}  // namespace vision
-}  // namespace tasks
-}  // namespace mediapipe

mediapipe/tasks/cc/vision/hand_gesture_recognizer/BUILD

@@ -54,10 +54,10 @@ cc_library(
         "//mediapipe/framework/formats:matrix",
         "//mediapipe/framework/formats:tensor",
         "//mediapipe/tasks/cc:common",
-        "//mediapipe/tasks/cc/components:classification_postprocessing",
-        "//mediapipe/tasks/cc/components:classification_postprocessing_options_cc_proto",
         "//mediapipe/tasks/cc/components:image_preprocessing",
-        "//mediapipe/tasks/cc/components/containers:classifications_cc_proto",
+        "//mediapipe/tasks/cc/components/containers/proto:classifications_cc_proto",
+        "//mediapipe/tasks/cc/components/processors:classification_postprocessing_graph",
+        "//mediapipe/tasks/cc/components/processors/proto:classification_postprocessing_graph_options_cc_proto",
         "//mediapipe/tasks/cc/core:model_resources",
         "//mediapipe/tasks/cc/core:model_task_graph",
         "//mediapipe/tasks/cc/core:utils",

mediapipe/tasks/cc/vision/hand_gesture_recognizer/hand_gesture_recognizer_subgraph.cc

@@ -27,9 +27,9 @@ limitations under the License.
 #include "mediapipe/framework/formats/matrix.h"
 #include "mediapipe/framework/formats/tensor.h"
 #include "mediapipe/tasks/cc/common.h"
-#include "mediapipe/tasks/cc/components/classification_postprocessing.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
-#include "mediapipe/tasks/cc/components/classification_postprocessing_options.pb.h"
+#include "mediapipe/tasks/cc/components/processors/classification_postprocessing_graph.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classification_postprocessing_graph_options.pb.h"
 #include "mediapipe/tasks/cc/core/model_resources.h"
 #include "mediapipe/tasks/cc/core/model_task_graph.h"
 #include "mediapipe/tasks/cc/core/proto/inference_subgraph.pb.h"
@@ -49,6 +49,7 @@ using ::mediapipe::api2::Input;
 using ::mediapipe::api2::Output;
 using ::mediapipe::api2::builder::Graph;
 using ::mediapipe::api2::builder::Source;
+using ::mediapipe::tasks::components::containers::proto::ClassificationResult;
 using ::mediapipe::tasks::vision::hand_gesture_recognizer::proto::
     HandGestureRecognizerSubgraphOptions;
 using ::mediapipe::tasks::vision::proto::LandmarksToMatrixCalculatorOptions;
@@ -218,11 +219,14 @@ class SingleHandGestureRecognizerSubgraph : public core::ModelTaskGraph {
     auto inference_output_tensors = inference.Out(kTensorsTag);
 
     auto& postprocessing = graph.AddNode(
-        "mediapipe.tasks.components.ClassificationPostprocessingSubgraph");
+        "mediapipe.tasks.components.processors."
-    MP_RETURN_IF_ERROR(ConfigureClassificationPostprocessing(
+        "ClassificationPostprocessingGraph");
+    MP_RETURN_IF_ERROR(
+        components::processors::ConfigureClassificationPostprocessingGraph(
             model_resources, graph_options.classifier_options(),
-        &postprocessing.GetOptions<
+            &postprocessing
-            tasks::components::ClassificationPostprocessingOptions>()));
+                 .GetOptions<components::processors::proto::
+                                 ClassificationPostprocessingGraphOptions>()));
     inference_output_tensors >> postprocessing.In(kTensorsTag);
     auto classification_result =
         postprocessing[Output<ClassificationResult>("CLASSIFICATION_RESULT")];

mediapipe/tasks/cc/vision/hand_gesture_recognizer/proto/BUILD

@@ -26,7 +26,7 @@ mediapipe_proto_library(
     deps = [
         "//mediapipe/framework:calculator_options_proto",
         "//mediapipe/framework:calculator_proto",
-        "//mediapipe/tasks/cc/components/proto:classifier_options_proto",
+        "//mediapipe/tasks/cc/components/processors/proto:classifier_options_proto",
         "//mediapipe/tasks/cc/core/proto:base_options_proto",
     ],
 )
@@ -37,7 +37,5 @@ mediapipe_proto_library(
     deps = [
         "//mediapipe/framework:calculator_options_proto",
         "//mediapipe/framework:calculator_proto",
-        "//mediapipe/tasks/cc/components/proto:classifier_options_proto",
-        "//mediapipe/tasks/cc/core/proto:base_options_proto",
     ],
 )

mediapipe/tasks/cc/vision/hand_gesture_recognizer/proto/hand_gesture_recognizer_subgraph_options.proto

@@ -18,7 +18,7 @@ syntax = "proto2";
 package mediapipe.tasks.vision.hand_gesture_recognizer.proto;
 
 import "mediapipe/framework/calculator.proto";
-import "mediapipe/tasks/cc/components/proto/classifier_options.proto";
+import "mediapipe/tasks/cc/components/processors/proto/classifier_options.proto";
 import "mediapipe/tasks/cc/core/proto/base_options.proto";
 
 message HandGestureRecognizerSubgraphOptions {
@@ -31,7 +31,7 @@ message HandGestureRecognizerSubgraphOptions {
 
   // Options for configuring the gesture classifier behavior, such as score
   // threshold, number of results, etc.
-  optional components.proto.ClassifierOptions classifier_options = 2;
+  optional components.processors.proto.ClassifierOptions classifier_options = 2;
 
   // Minimum confidence value ([0.0, 1.0]) for the hand landmarks to be
   // considered tracked successfully

mediapipe/tasks/cc/vision/hand_landmarker/calculators/BUILD

@@ -0,0 +1,49 @@
+# Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+load("//mediapipe/framework/port:build_config.bzl", "mediapipe_proto_library")
+
+package(default_visibility = [
+    "//mediapipe/app/xeno:__subpackages__",
+    "//mediapipe/tasks:internal",
+])
+
+licenses(["notice"])
+
+mediapipe_proto_library(
+    name = "hand_association_calculator_proto",
+    srcs = ["hand_association_calculator.proto"],
+    deps = [
+        "//mediapipe/framework:calculator_options_proto",
+        "//mediapipe/framework:calculator_proto",
+    ],
+)
+
+cc_library(
+    name = "hand_association_calculator",
+    srcs = ["hand_association_calculator.cc"],
+    deps = [
+        ":hand_association_calculator_cc_proto",
+        "//mediapipe/calculators/util:association_calculator",
+        "//mediapipe/framework:calculator_framework",
+        "//mediapipe/framework/api2:node",
+        "//mediapipe/framework/formats:rect_cc_proto",
+        "//mediapipe/framework/port:rectangle",
+        "//mediapipe/framework/port:status",
+        "//mediapipe/util:rectangle_util",
+    ],
+    alwayslink = 1,
+)
+
+# TODO: Enable this test

mediapipe/tasks/cc/vision/hand_landmarker/calculators/hand_association_calculator.cc

@@ -0,0 +1,125 @@
+/* Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+==============================================================================*/
+
+#include <memory>
+#include <utility>
+#include <vector>
+
+#include "mediapipe/framework/api2/node.h"
+#include "mediapipe/framework/calculator_framework.h"
+#include "mediapipe/framework/formats/rect.pb.h"
+#include "mediapipe/framework/port/rectangle.h"
+#include "mediapipe/framework/port/status.h"
+#include "mediapipe/tasks/cc/vision/hand_landmarker/calculators/hand_association_calculator.pb.h"
+#include "mediapipe/util/rectangle_util.h"
+
+namespace mediapipe::api2 {
+
+// HandAssociationCalculator accepts multiple inputs of vectors of
+// NormalizedRect. The output is a vector of NormalizedRect that contains
+// rects from the input vectors that don't overlap with each other. When two
+// rects overlap, the rect that comes in from an earlier input stream is
+// kept in the output. If a rect has no ID (i.e. from detection stream),
+// then a unique rect ID is assigned for it.
+
+// The rects in multiple input streams are effectively flattened to a single
+// list.  For example:
+// Stream1 : rect 1, rect 2
+// Stream2:  rect 3, rect 4
+// Stream3: rect 5, rect 6
+// (Conceptually) flattened list : rect 1, 2, 3, 4, 5, 6
+// In the flattened list, if a rect with a higher index overlaps with a rect a
+// lower index, beyond a specified IOU threshold, the rect with the lower
+// index will be in the output, and the rect with higher index will be
+// discarded.
+// TODO: Upgrade this to latest API for calculators
+class HandAssociationCalculator : public CalculatorBase {
+ public:
+  static absl::Status GetContract(CalculatorContract* cc) {
+    // Initialize input and output streams.
+    for (auto& input_stream : cc->Inputs()) {
+      input_stream.Set<std::vector<NormalizedRect>>();
+    }
+    cc->Outputs().Index(0).Set<std::vector<NormalizedRect>>();
+
+    return absl::OkStatus();
+  }
+
+  absl::Status Open(CalculatorContext* cc) override {
+    cc->SetOffset(TimestampDiff(0));
+
+    options_ = cc->Options<HandAssociationCalculatorOptions>();
+    CHECK_GT(options_.min_similarity_threshold(), 0.0);
+    CHECK_LE(options_.min_similarity_threshold(), 1.0);
+
+    return absl::OkStatus();
+  }
+
+  absl::Status Process(CalculatorContext* cc) override {
+    ASSIGN_OR_RETURN(auto result, GetNonOverlappingElements(cc));
+
+    auto output =
+        std::make_unique<std::vector<NormalizedRect>>(std::move(result));
+    cc->Outputs().Index(0).Add(output.release(), cc->InputTimestamp());
+
+    return absl::OkStatus();
+  }
+
+ private:
+  HandAssociationCalculatorOptions options_;
+
+  // Return a list of non-overlapping elements from all input streams, with
+  // decreasing order of priority based on input stream index and indices
+  // within an input stream.
+  absl::StatusOr<std::vector<NormalizedRect>> GetNonOverlappingElements(
+      CalculatorContext* cc) {
+    std::vector<NormalizedRect> result;
+
+    for (const auto& input_stream : cc->Inputs()) {
+      if (input_stream.IsEmpty()) {
+        continue;
+      }
+
+      for (auto rect : input_stream.Get<std::vector<NormalizedRect>>()) {
+        ASSIGN_OR_RETURN(
+            bool is_overlapping,
+            mediapipe::DoesRectOverlap(rect, result,
+                                       options_.min_similarity_threshold()));
+        if (!is_overlapping) {
+          if (!rect.has_rect_id()) {
+            rect.set_rect_id(GetNextRectId());
+          }
+          result.push_back(rect);
+        }
+      }
+    }
+
+    return result;
+  }
+
+ private:
+  // Each NormalizedRect processed by the calculator will be assigned
+  // an unique id, if it does not already have an ID. The starting ID will be 1.
+  // Note: This rect_id_ is local to an instance of this calculator. And it is
+  // expected that the hand tracking graph to have only one instance of
+  // this association calculator.
+  int64 rect_id_ = 1;
+
+  inline int GetNextRectId() { return rect_id_++; }
+};
+
+MEDIAPIPE_REGISTER_NODE(HandAssociationCalculator);
+
+}  // namespace mediapipe::api2

mediapipe/tasks/cc/vision/hand_landmarker/calculators/hand_association_calculator.proto

@@ -13,22 +13,16 @@ See the License for the specific language governing permissions and
 limitations under the License.
 ==============================================================================*/
 
-#ifndef MEDIAPIPE_TASKS_CC_VISION_HAND_DETECTOR_HAND_DETECTOR_OP_RESOLVER_H_
+syntax = "proto2";
-#define MEDIAPIPE_TASKS_CC_VISION_HAND_DETECTOR_HAND_DETECTOR_OP_RESOLVER_H_
 
-#include "tensorflow/lite/kernels/register.h"
+package mediapipe;
 
-namespace mediapipe {
+import "mediapipe/framework/calculator.proto";
-namespace tasks {
-namespace vision {
-class HandDetectorOpResolver : public tflite::ops::builtin::BuiltinOpResolver {
- public:
-  HandDetectorOpResolver();
-  HandDetectorOpResolver(const HandDetectorOpResolver& r) = delete;
-};
 
-}  // namespace vision
+message HandAssociationCalculatorOptions {
-}  // namespace tasks
+  extend mediapipe.CalculatorOptions {
-}  // namespace mediapipe
+    optional HandAssociationCalculatorOptions ext = 408244367;
+  }
 
-#endif  // MEDIAPIPE_TASKS_CC_VISION_HAND_DETECTOR_HAND_DETECTOR_OP_RESOLVER_H_
+  optional float min_similarity_threshold = 1 [default = 1.0];
+}

mediapipe/tasks/cc/vision/hand_landmarker/calculators/hand_association_calculator_test.cc

@@ -0,0 +1,302 @@
+/* Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+==============================================================================*/
+
+#include <memory>
+#include <vector>
+
+#include "mediapipe/framework/calculator_runner.h"
+#include "mediapipe/framework/formats/rect.pb.h"
+#include "mediapipe/framework/packet.h"
+#include "mediapipe/framework/port/gmock.h"
+#include "mediapipe/framework/port/gtest.h"
+#include "mediapipe/framework/port/parse_text_proto.h"
+
+namespace mediapipe {
+namespace {
+
+class HandAssociationCalculatorTest : public testing::Test {
+ protected:
+  HandAssociationCalculatorTest() {
+    //  0.4                                         ================
+    //                                              |    |    |    |
+    //  0.3 =====================                   |   NR2   |    |
+    //      |    |    |   NR1   |                   |    |    NR4  |
+    //  0.2 |   NR0   |    ===========              ================
+    //      |    |    |    |    |    |
+    //  0.1 =====|===============    |
+    //           |    NR3  |    |    |
+    //  0.0      ================    |
+    //                     |   NR5   |
+    // -0.1                ===========
+    //     0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9  1.0  1.1  1.2
+
+    // NormalizedRect nr_0.
+    nr_0_.set_x_center(0.2);
+    nr_0_.set_y_center(0.2);
+    nr_0_.set_width(0.2);
+    nr_0_.set_height(0.2);
+
+    // NormalizedRect nr_1.
+    nr_1_.set_x_center(0.4);
+    nr_1_.set_y_center(0.2);
+    nr_1_.set_width(0.2);
+    nr_1_.set_height(0.2);
+
+    // NormalizedRect nr_2.
+    nr_2_.set_x_center(1.0);
+    nr_2_.set_y_center(0.3);
+    nr_2_.set_width(0.2);
+    nr_2_.set_height(0.2);
+
+    // NormalizedRect nr_3.
+    nr_3_.set_x_center(0.35);
+    nr_3_.set_y_center(0.15);
+    nr_3_.set_width(0.3);
+    nr_3_.set_height(0.3);
+
+    // NormalizedRect nr_4.
+    nr_4_.set_x_center(1.1);
+    nr_4_.set_y_center(0.3);
+    nr_4_.set_width(0.2);
+    nr_4_.set_height(0.2);
+
+    // NormalizedRect nr_5.
+    nr_5_.set_x_center(0.5);
+    nr_5_.set_y_center(0.05);
+    nr_5_.set_width(0.3);
+    nr_5_.set_height(0.3);
+  }
+
+  NormalizedRect nr_0_, nr_1_, nr_2_, nr_3_, nr_4_, nr_5_;
+};
+
+TEST_F(HandAssociationCalculatorTest, NormRectAssocTest) {
+  CalculatorRunner runner(ParseTextProtoOrDie<CalculatorGraphConfig::Node>(R"pb(
+    calculator: "HandAssociationCalculator"
+    input_stream: "input_vec_0"
+    input_stream: "input_vec_1"
+    input_stream: "input_vec_2"
+    output_stream: "output_vec"
+    options {
+      [mediapipe.HandAssociationCalculatorOptions.ext] {
+        min_similarity_threshold: 0.1
+      }
+    }
+  )pb"));
+
+  // Input Stream 0: nr_0, nr_1, nr_2.
+  auto input_vec_0 = std::make_unique<std::vector<NormalizedRect>>();
+  input_vec_0->push_back(nr_0_);
+  input_vec_0->push_back(nr_1_);
+  input_vec_0->push_back(nr_2_);
+  runner.MutableInputs()->Index(0).packets.push_back(
+      Adopt(input_vec_0.release()).At(Timestamp(1)));
+
+  // Input Stream 1: nr_3, nr_4.
+  auto input_vec_1 = std::make_unique<std::vector<NormalizedRect>>();
+  input_vec_1->push_back(nr_3_);
+  input_vec_1->push_back(nr_4_);
+  runner.MutableInputs()->Index(1).packets.push_back(
+      Adopt(input_vec_1.release()).At(Timestamp(1)));
+
+  // Input Stream 2: nr_5.
+  auto input_vec_2 = std::make_unique<std::vector<NormalizedRect>>();
+  input_vec_2->push_back(nr_5_);
+  runner.MutableInputs()->Index(2).packets.push_back(
+      Adopt(input_vec_2.release()).At(Timestamp(1)));
+
+  MP_ASSERT_OK(runner.Run()) << "Calculator execution failed.";
+  const std::vector<Packet>& output = runner.Outputs().Index(0).packets;
+  EXPECT_EQ(1, output.size());
+  auto assoc_rects = output[0].Get<std::vector<NormalizedRect>>();
+
+  // Rectangles are added in the following sequence:
+  // nr_0 is added 1st.
+  // nr_1 is added because it does not overlap with nr_0.
+  // nr_2 is added because it does not overlap with nr_0 or nr_1.
+  // nr_3 is NOT added because it overlaps with nr_0.
+  // nr_4 is NOT added because it overlaps with nr_2.
+  // nr_5 is NOT added because it overlaps with nr_1.
+  EXPECT_EQ(3, assoc_rects.size());
+
+  // Check that IDs are filled in and contents match.
+  EXPECT_EQ(assoc_rects[0].rect_id(), 1);
+  assoc_rects[0].clear_rect_id();
+  EXPECT_THAT(assoc_rects[0], testing::EqualsProto(nr_0_));
+
+  EXPECT_EQ(assoc_rects[1].rect_id(), 2);
+  assoc_rects[1].clear_rect_id();
+  EXPECT_THAT(assoc_rects[1], testing::EqualsProto(nr_1_));
+
+  EXPECT_EQ(assoc_rects[2].rect_id(), 3);
+  assoc_rects[2].clear_rect_id();
+  EXPECT_THAT(assoc_rects[2], testing::EqualsProto(nr_2_));
+}
+
+TEST_F(HandAssociationCalculatorTest, NormRectAssocTestWithTrackedHands) {
+  CalculatorRunner runner(ParseTextProtoOrDie<CalculatorGraphConfig::Node>(R"pb(
+    calculator: "HandAssociationCalculator"
+    input_stream: "input_vec_0"
+    input_stream: "input_vec_1"
+    input_stream: "input_vec_2"
+    output_stream: "output_vec"
+    options {
+      [mediapipe.HandAssociationCalculatorOptions.ext] {
+        min_similarity_threshold: 0.1
+      }
+    }
+  )pb"));
+
+  // Input Stream 0: nr_0, nr_1.  Tracked hands.
+  auto input_vec_0 = std::make_unique<std::vector<NormalizedRect>>();
+  // Setting ID to a negative number for test only, since newly generated
+  // ID by HandAssociationCalculator are positive numbers.
+  nr_0_.set_rect_id(-2);
+  input_vec_0->push_back(nr_0_);
+  nr_1_.set_rect_id(-1);
+  input_vec_0->push_back(nr_1_);
+  runner.MutableInputs()->Index(0).packets.push_back(
+      Adopt(input_vec_0.release()).At(Timestamp(1)));
+
+  // Input Stream 1: nr_2, nr_3. Newly detected palms.
+  auto input_vec_1 = std::make_unique<std::vector<NormalizedRect>>();
+  input_vec_1->push_back(nr_2_);
+  input_vec_1->push_back(nr_3_);
+  runner.MutableInputs()->Index(1).packets.push_back(
+      Adopt(input_vec_1.release()).At(Timestamp(1)));
+
+  MP_ASSERT_OK(runner.Run()) << "Calculator execution failed.";
+  const std::vector<Packet>& output = runner.Outputs().Index(0).packets;
+  EXPECT_EQ(1, output.size());
+  auto assoc_rects = output[0].Get<std::vector<NormalizedRect>>();
+
+  // Rectangles are added in the following sequence:
+  // nr_0 is added 1st.
+  // nr_1 is added because it does not overlap with nr_0.
+  // nr_2 is added because it does not overlap with nr_0 or nr_1.
+  // nr_3 is NOT added because it overlaps with nr_0.
+  EXPECT_EQ(3, assoc_rects.size());
+
+  // Check that IDs are filled in and contents match.
+  EXPECT_EQ(assoc_rects[0].rect_id(), -2);
+  EXPECT_THAT(assoc_rects[0], testing::EqualsProto(nr_0_));
+
+  EXPECT_EQ(assoc_rects[1].rect_id(), -1);
+  EXPECT_THAT(assoc_rects[1], testing::EqualsProto(nr_1_));
+
+  EXPECT_EQ(assoc_rects[2].rect_id(), 1);
+  assoc_rects[2].clear_rect_id();
+  EXPECT_THAT(assoc_rects[2], testing::EqualsProto(nr_2_));
+}
+
+TEST_F(HandAssociationCalculatorTest, NormRectAssocTestReverse) {
+  CalculatorRunner runner(ParseTextProtoOrDie<CalculatorGraphConfig::Node>(R"pb(
+    calculator: "HandAssociationCalculator"
+    input_stream: "input_vec_0"
+    input_stream: "input_vec_1"
+    input_stream: "input_vec_2"
+    output_stream: "output_vec"
+    options {
+      [mediapipe.HandAssociationCalculatorOptions.ext] {
+        min_similarity_threshold: 0.1
+      }
+    }
+  )pb"));
+
+  // Input Stream 0: nr_5.
+  auto input_vec_0 = std::make_unique<std::vector<NormalizedRect>>();
+  input_vec_0->push_back(nr_5_);
+  runner.MutableInputs()->Index(0).packets.push_back(
+      Adopt(input_vec_0.release()).At(Timestamp(1)));
+
+  // Input Stream 1: nr_4, nr_3
+  auto input_vec_1 = std::make_unique<std::vector<NormalizedRect>>();
+  input_vec_1->push_back(nr_4_);
+  input_vec_1->push_back(nr_3_);
+  runner.MutableInputs()->Index(1).packets.push_back(
+      Adopt(input_vec_1.release()).At(Timestamp(1)));
+
+  // Input Stream 2: nr_2, nr_1, nr_0.
+  auto input_vec_2 = std::make_unique<std::vector<NormalizedRect>>();
+  input_vec_2->push_back(nr_2_);
+  input_vec_2->push_back(nr_1_);
+  input_vec_2->push_back(nr_0_);
+  runner.MutableInputs()->Index(2).packets.push_back(
+      Adopt(input_vec_2.release()).At(Timestamp(1)));
+
+  MP_ASSERT_OK(runner.Run()) << "Calculator execution failed.";
+  const std::vector<Packet>& output = runner.Outputs().Index(0).packets;
+  EXPECT_EQ(1, output.size());
+  auto assoc_rects = output[0].Get<std::vector<NormalizedRect>>();
+
+  // Rectangles are added in the following sequence:
+  // nr_5 is added 1st.
+  // nr_4 is added because it does not overlap with nr_5.
+  // nr_3 is NOT added because it overlaps with nr_5.
+  // nr_2 is NOT added because it overlaps with nr_4.
+  // nr_1 is NOT added because it overlaps with nr_5.
+  // nr_0 is added because it does not overlap with nr_5 or nr_4.
+  EXPECT_EQ(3, assoc_rects.size());
+
+  // Outputs are in same order as inputs, and IDs are filled in.
+  EXPECT_EQ(assoc_rects[0].rect_id(), 1);
+  assoc_rects[0].clear_rect_id();
+  EXPECT_THAT(assoc_rects[0], testing::EqualsProto(nr_5_));
+
+  EXPECT_EQ(assoc_rects[1].rect_id(), 2);
+  assoc_rects[1].clear_rect_id();
+  EXPECT_THAT(assoc_rects[1], testing::EqualsProto(nr_4_));
+
+  EXPECT_EQ(assoc_rects[2].rect_id(), 3);
+  assoc_rects[2].clear_rect_id();
+  EXPECT_THAT(assoc_rects[2], testing::EqualsProto(nr_0_));
+}
+
+TEST_F(HandAssociationCalculatorTest, NormRectAssocSingleInputStream) {
+  CalculatorRunner runner(ParseTextProtoOrDie<CalculatorGraphConfig::Node>(R"pb(
+    calculator: "HandAssociationCalculator"
+    input_stream: "input_vec"
+    output_stream: "output_vec"
+    options {
+      [mediapipe.HandAssociationCalculatorOptions.ext] {
+        min_similarity_threshold: 0.1
+      }
+    }
+  )pb"));
+
+  // Just one input stream : nr_3, nr_5.
+  auto input_vec = std::make_unique<std::vector<NormalizedRect>>();
+  input_vec->push_back(nr_3_);
+  input_vec->push_back(nr_5_);
+  runner.MutableInputs()->Index(0).packets.push_back(
+      Adopt(input_vec.release()).At(Timestamp(1)));
+
+  MP_ASSERT_OK(runner.Run()) << "Calculator execution failed.";
+  const std::vector<Packet>& output = runner.Outputs().Index(0).packets;
+  EXPECT_EQ(1, output.size());
+  auto assoc_rects = output[0].Get<std::vector<NormalizedRect>>();
+
+  // Rectangles are added in the following sequence:
+  // nr_3 is added 1st.
+  // nr_5 is NOT added because it overlaps with nr_3.
+  EXPECT_EQ(1, assoc_rects.size());
+
+  EXPECT_EQ(assoc_rects[0].rect_id(), 1);
+  assoc_rects[0].clear_rect_id();
+  EXPECT_THAT(assoc_rects[0], testing::EqualsProto(nr_3_));
+}
+
+}  // namespace
+}  // namespace mediapipe

mediapipe/tasks/cc/vision/image_classifier/BUILD

@@ -26,14 +26,14 @@ cc_library(
         "//mediapipe/framework/api2:port",
         "//mediapipe/framework/formats:image",
         "//mediapipe/framework/formats:rect_cc_proto",
-        "//mediapipe/tasks/cc/components:classification_postprocessing",
-        "//mediapipe/tasks/cc/components:classification_postprocessing_options_cc_proto",
         "//mediapipe/tasks/cc/components:image_preprocessing",
         "//mediapipe/tasks/cc/components:image_preprocessing_options_cc_proto",
-        "//mediapipe/tasks/cc/components/containers:classifications_cc_proto",
+        "//mediapipe/tasks/cc/components/containers/proto:classifications_cc_proto",
+        "//mediapipe/tasks/cc/components/processors:classification_postprocessing_graph",
+        "//mediapipe/tasks/cc/components/processors/proto:classification_postprocessing_graph_options_cc_proto",
         "//mediapipe/tasks/cc/core:model_resources",
         "//mediapipe/tasks/cc/core:model_task_graph",
-        "//mediapipe/tasks/cc/vision/image_classifier/proto:image_classifier_options_cc_proto",
+        "//mediapipe/tasks/cc/vision/image_classifier/proto:image_classifier_graph_options_cc_proto",
         "@com_google_absl//absl/status:statusor",
     ],
     alwayslink = 1,
@@ -50,9 +50,9 @@ cc_library(
         "//mediapipe/framework/api2:builder",
         "//mediapipe/framework/formats:image",
         "//mediapipe/framework/formats:rect_cc_proto",
-        "//mediapipe/tasks/cc/components:classifier_options",
+        "//mediapipe/tasks/cc/components/containers/proto:classifications_cc_proto",
-        "//mediapipe/tasks/cc/components/containers:classifications_cc_proto",
+        "//mediapipe/tasks/cc/components/processors:classifier_options",
-        "//mediapipe/tasks/cc/components/proto:classifier_options_cc_proto",
+        "//mediapipe/tasks/cc/components/processors/proto:classifier_options_cc_proto",
         "//mediapipe/tasks/cc/core:base_options",
         "//mediapipe/tasks/cc/core:task_runner",
         "//mediapipe/tasks/cc/core:utils",
@@ -61,7 +61,7 @@ cc_library(
         "//mediapipe/tasks/cc/vision/core:base_vision_task_api",
         "//mediapipe/tasks/cc/vision/core:running_mode",
         "//mediapipe/tasks/cc/vision/core:vision_task_api_factory",
-        "//mediapipe/tasks/cc/vision/image_classifier/proto:image_classifier_options_cc_proto",
+        "//mediapipe/tasks/cc/vision/image_classifier/proto:image_classifier_graph_options_cc_proto",
         "@com_google_absl//absl/status",
         "@com_google_absl//absl/status:statusor",
     ],

mediapipe/tasks/cc/vision/image_classifier/image_classifier.cc

@@ -26,9 +26,9 @@ limitations under the License.
 #include "mediapipe/framework/formats/rect.pb.h"
 #include "mediapipe/framework/packet.h"
 #include "mediapipe/framework/timestamp.h"
-#include "mediapipe/tasks/cc/components/classifier_options.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/processors/classifier_options.h"
-#include "mediapipe/tasks/cc/components/proto/classifier_options.pb.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classifier_options.pb.h"
 #include "mediapipe/tasks/cc/core/base_options.h"
 #include "mediapipe/tasks/cc/core/proto/base_options.pb.h"
 #include "mediapipe/tasks/cc/core/proto/inference_subgraph.pb.h"
@@ -36,11 +36,12 @@ limitations under the License.
 #include "mediapipe/tasks/cc/core/utils.h"
 #include "mediapipe/tasks/cc/vision/core/running_mode.h"
 #include "mediapipe/tasks/cc/vision/core/vision_task_api_factory.h"
-#include "mediapipe/tasks/cc/vision/image_classifier/proto/image_classifier_options.pb.h"
+#include "mediapipe/tasks/cc/vision/image_classifier/proto/image_classifier_graph_options.pb.h"
 
 namespace mediapipe {
 namespace tasks {
 namespace vision {
+namespace image_classifier {
 
 namespace {
 
@@ -52,12 +53,11 @@ constexpr char kImageTag[] = "IMAGE";
 constexpr char kNormRectName[] = "norm_rect_in";
 constexpr char kNormRectTag[] = "NORM_RECT";
 constexpr char kSubgraphTypeName[] =
-    "mediapipe.tasks.vision.ImageClassifierGraph";
+    "mediapipe.tasks.vision.image_classifier.ImageClassifierGraph";
 constexpr int kMicroSecondsPerMilliSecond = 1000;
 
+using ::mediapipe::tasks::components::containers::proto::ClassificationResult;
 using ::mediapipe::tasks::core::PacketMap;
-using ImageClassifierOptionsProto =
-    image_classifier::proto::ImageClassifierOptions;
 
 // Builds a NormalizedRect covering the entire image.
 NormalizedRect BuildFullImageNormRect() {
@@ -70,17 +70,17 @@ NormalizedRect BuildFullImageNormRect() {
 }
 
 // Creates a MediaPipe graph config that contains a subgraph node of
-// "mediapipe.tasks.vision.ImageClassifierGraph". If the task is running in the
+// type "ImageClassifierGraph". If the task is running in the live stream mode,
-// live stream mode, a "FlowLimiterCalculator" will be added to limit the number
+// a "FlowLimiterCalculator" will be added to limit the number of frames in
-// of frames in flight.
+// flight.
 CalculatorGraphConfig CreateGraphConfig(
-    std::unique_ptr<ImageClassifierOptionsProto> options_proto,
+    std::unique_ptr<proto::ImageClassifierGraphOptions> options_proto,
     bool enable_flow_limiting) {
   api2::builder::Graph graph;
   graph.In(kImageTag).SetName(kImageInStreamName);
   graph.In(kNormRectTag).SetName(kNormRectName);
   auto& task_subgraph = graph.AddNode(kSubgraphTypeName);
-  task_subgraph.GetOptions<ImageClassifierOptionsProto>().Swap(
+  task_subgraph.GetOptions<proto::ImageClassifierGraphOptions>().Swap(
       options_proto.get());
   task_subgraph.Out(kClassificationResultTag)
           .SetName(kClassificationResultStreamName) >>
@@ -98,18 +98,18 @@ CalculatorGraphConfig CreateGraphConfig(
 }
 
 // Converts the user-facing ImageClassifierOptions struct to the internal
-// ImageClassifierOptions proto.
+// ImageClassifierGraphOptions proto.
-std::unique_ptr<ImageClassifierOptionsProto>
+std::unique_ptr<proto::ImageClassifierGraphOptions>
 ConvertImageClassifierOptionsToProto(ImageClassifierOptions* options) {
-  auto options_proto = std::make_unique<ImageClassifierOptionsProto>();
+  auto options_proto = std::make_unique<proto::ImageClassifierGraphOptions>();
   auto base_options_proto = std::make_unique<tasks::core::proto::BaseOptions>(
       tasks::core::ConvertBaseOptionsToProto(&(options->base_options)));
   options_proto->mutable_base_options()->Swap(base_options_proto.get());
   options_proto->mutable_base_options()->set_use_stream_mode(
       options->running_mode != core::RunningMode::IMAGE);
   auto classifier_options_proto =
-      std::make_unique<tasks::components::proto::ClassifierOptions>(
+      std::make_unique<components::processors::proto::ClassifierOptions>(
-          components::ConvertClassifierOptionsToProto(
+          components::processors::ConvertClassifierOptionsToProto(
               &(options->classifier_options)));
   options_proto->mutable_classifier_options()->Swap(
       classifier_options_proto.get());
@@ -145,7 +145,7 @@ absl::StatusOr<std::unique_ptr<ImageClassifier>> ImageClassifier::Create(
         };
   }
   return core::VisionTaskApiFactory::Create<ImageClassifier,
-                                            ImageClassifierOptionsProto>(
+                                            proto::ImageClassifierGraphOptions>(
       CreateGraphConfig(
           std::move(options_proto),
           options->running_mode == core::RunningMode::LIVE_STREAM),
@@ -214,6 +214,7 @@ absl::Status ImageClassifier::ClassifyAsync(Image image, int64 timestamp_ms,
             .At(Timestamp(timestamp_ms * kMicroSecondsPerMilliSecond))}});
 }
 
+}  // namespace image_classifier
 }  // namespace vision
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/vision/image_classifier/image_classifier.h

@@ -23,8 +23,8 @@ limitations under the License.
 #include "absl/status/statusor.h"
 #include "mediapipe/framework/formats/image.h"
 #include "mediapipe/framework/formats/rect.pb.h"
-#include "mediapipe/tasks/cc/components/classifier_options.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/processors/classifier_options.h"
 #include "mediapipe/tasks/cc/core/base_options.h"
 #include "mediapipe/tasks/cc/vision/core/base_vision_task_api.h"
 #include "mediapipe/tasks/cc/vision/core/running_mode.h"
@@ -32,6 +32,7 @@ limitations under the License.
 namespace mediapipe {
 namespace tasks {
 namespace vision {
+namespace image_classifier {
 
 // The options for configuring a Mediapipe image classifier task.
 struct ImageClassifierOptions {
@@ -50,12 +51,14 @@ struct ImageClassifierOptions {
 
   // Options for configuring the classifier behavior, such as score threshold,
   // number of results, etc.
-  components::ClassifierOptions classifier_options;
+  components::processors::ClassifierOptions classifier_options;
 
   // The user-defined result callback for processing live stream data.
   // The result callback should only be specified when the running mode is set
   // to RunningMode::LIVE_STREAM.
-  std::function<void(absl::StatusOr<ClassificationResult>, const Image&, int64)>
+  std::function<void(
+      absl::StatusOr<components::containers::proto::ClassificationResult>,
+      const Image&, int64)>
       result_callback = nullptr;
 };
 
@@ -112,7 +115,7 @@ class ImageClassifier : tasks::vision::core::BaseVisionTaskApi {
   // The image can be of any size with format RGB or RGBA.
   // TODO: describe exact preprocessing steps once
   // YUVToImageCalculator is integrated.
-  absl::StatusOr<ClassificationResult> Classify(
+  absl::StatusOr<components::containers::proto::ClassificationResult> Classify(
       mediapipe::Image image,
       std::optional<mediapipe::NormalizedRect> roi = std::nullopt);
 
@@ -126,8 +129,8 @@ class ImageClassifier : tasks::vision::core::BaseVisionTaskApi {
   // The image can be of any size with format RGB or RGBA. It's required to
   // provide the video frame's timestamp (in milliseconds). The input timestamps
   // must be monotonically increasing.
-  absl::StatusOr<ClassificationResult> ClassifyForVideo(
+  absl::StatusOr<components::containers::proto::ClassificationResult>
-      mediapipe::Image image, int64 timestamp_ms,
+  ClassifyForVideo(mediapipe::Image image, int64 timestamp_ms,
                    std::optional<mediapipe::NormalizedRect> roi = std::nullopt);
 
   // Sends live image data to image classification, and the results will be
@@ -161,6 +164,7 @@ class ImageClassifier : tasks::vision::core::BaseVisionTaskApi {
   absl::Status Close() { return runner_->Close(); }
 };
 
+}  // namespace image_classifier
 }  // namespace vision
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/vision/image_classifier/image_classifier_graph.cc

@@ -22,18 +22,19 @@ limitations under the License.
 #include "mediapipe/framework/calculator_framework.h"
 #include "mediapipe/framework/formats/image.h"
 #include "mediapipe/framework/formats/rect.pb.h"
-#include "mediapipe/tasks/cc/components/classification_postprocessing.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
-#include "mediapipe/tasks/cc/components/classification_postprocessing_options.pb.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
 #include "mediapipe/tasks/cc/components/image_preprocessing.h"
 #include "mediapipe/tasks/cc/components/image_preprocessing_options.pb.h"
+#include "mediapipe/tasks/cc/components/processors/classification_postprocessing_graph.h"
+#include "mediapipe/tasks/cc/components/processors/proto/classification_postprocessing_graph_options.pb.h"
 #include "mediapipe/tasks/cc/core/model_resources.h"
 #include "mediapipe/tasks/cc/core/model_task_graph.h"
-#include "mediapipe/tasks/cc/vision/image_classifier/proto/image_classifier_options.pb.h"
+#include "mediapipe/tasks/cc/vision/image_classifier/proto/image_classifier_graph_options.pb.h"
 
 namespace mediapipe {
 namespace tasks {
 namespace vision {
+namespace image_classifier {
 
 namespace {
 
@@ -42,8 +43,7 @@ using ::mediapipe::api2::Output;
 using ::mediapipe::api2::builder::GenericNode;
 using ::mediapipe::api2::builder::Graph;
 using ::mediapipe::api2::builder::Source;
-using ImageClassifierOptionsProto =
+using ::mediapipe::tasks::components::containers::proto::ClassificationResult;
-    image_classifier::proto::ImageClassifierOptions;
 
 constexpr float kDefaultScoreThreshold = std::numeric_limits<float>::lowest();
 
@@ -61,8 +61,7 @@ struct ImageClassifierOutputStreams {
 
 }  // namespace
 
-// A "mediapipe.tasks.vision.ImageClassifierGraph" performs image
+// An "ImageClassifierGraph" performs image classification.
-// classification.
 // - Accepts CPU input images and outputs classifications on CPU.
 //
 // Inputs:
@@ -80,12 +79,12 @@ struct ImageClassifierOutputStreams {
 //
 // Example:
 // node {
-//   calculator: "mediapipe.tasks.vision.ImageClassifierGraph"
+//   calculator: "mediapipe.tasks.vision.image_classifier.ImageClassifierGraph"
 //   input_stream: "IMAGE:image_in"
 //   output_stream: "CLASSIFICATION_RESULT:classification_result_out"
 //   output_stream: "IMAGE:image_out"
 //   options {
-//     [mediapipe.tasks.vision.image_classifier.proto.ImageClassifierOptions.ext]
+//     [mediapipe.tasks.vision.image_classifier.proto.ImageClassifierGraphOptions.ext]
 //     {
 //       base_options {
 //         model_asset {
@@ -104,13 +103,14 @@ class ImageClassifierGraph : public core::ModelTaskGraph {
  public:
   absl::StatusOr<CalculatorGraphConfig> GetConfig(
       SubgraphContext* sc) override {
-    ASSIGN_OR_RETURN(const auto* model_resources,
+    ASSIGN_OR_RETURN(
-                     CreateModelResources<ImageClassifierOptionsProto>(sc));
+        const auto* model_resources,
+        CreateModelResources<proto::ImageClassifierGraphOptions>(sc));
     Graph graph;
     ASSIGN_OR_RETURN(
         auto output_streams,
         BuildImageClassificationTask(
-            sc->Options<ImageClassifierOptionsProto>(), *model_resources,
+            sc->Options<proto::ImageClassifierGraphOptions>(), *model_resources,
             graph[Input<Image>(kImageTag)],
             graph[Input<NormalizedRect>::Optional(kNormRectTag)], graph));
     output_streams.classification_result >>
@@ -125,13 +125,13 @@ class ImageClassifierGraph : public core::ModelTaskGraph {
   // (mediapipe::Image) as input and returns one classification result per input
   // image.
   //
-  // task_options: the mediapipe tasks ImageClassifierOptions.
+  // task_options: the mediapipe tasks ImageClassifierGraphOptions.
   // model_resources: the ModelSources object initialized from an image
   // classification model file with model metadata.
   // image_in: (mediapipe::Image) stream to run classification on.
   // graph: the mediapipe builder::Graph instance to be updated.
   absl::StatusOr<ImageClassifierOutputStreams> BuildImageClassificationTask(
-      const ImageClassifierOptionsProto& task_options,
+      const proto::ImageClassifierGraphOptions& task_options,
       const core::ModelResources& model_resources, Source<Image> image_in,
       Source<NormalizedRect> norm_rect_in, Graph& graph) {
     // Adds preprocessing calculators and connects them to the graph input image
@@ -153,11 +153,14 @@ class ImageClassifierGraph : public core::ModelTaskGraph {
 
     // Adds postprocessing calculators and connects them to the graph output.
     auto& postprocessing = graph.AddNode(
-        "mediapipe.tasks.components.ClassificationPostprocessingSubgraph");
+        "mediapipe.tasks.components.processors."
-    MP_RETURN_IF_ERROR(ConfigureClassificationPostprocessing(
+        "ClassificationPostprocessingGraph");
+    MP_RETURN_IF_ERROR(
+        components::processors::ConfigureClassificationPostprocessingGraph(
             model_resources, task_options.classifier_options(),
-        &postprocessing.GetOptions<
+            &postprocessing
-            tasks::components::ClassificationPostprocessingOptions>()));
+                 .GetOptions<components::processors::proto::
+                                 ClassificationPostprocessingGraphOptions>()));
     inference.Out(kTensorsTag) >> postprocessing.In(kTensorsTag);
 
     // Outputs the aggregated classification result as the subgraph output
@@ -168,8 +171,10 @@ class ImageClassifierGraph : public core::ModelTaskGraph {
         /*image=*/preprocessing[Output<Image>(kImageTag)]};
   }
 };
-REGISTER_MEDIAPIPE_GRAPH(::mediapipe::tasks::vision::ImageClassifierGraph);
+REGISTER_MEDIAPIPE_GRAPH(
+    ::mediapipe::tasks::vision::image_classifier::ImageClassifierGraph);
 
+}  // namespace image_classifier
 }  // namespace vision
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/vision/image_classifier/image_classifier_test.cc

@@ -32,8 +32,8 @@ limitations under the License.
 #include "mediapipe/framework/port/parse_text_proto.h"
 #include "mediapipe/framework/port/status_matchers.h"
 #include "mediapipe/tasks/cc/common.h"
-#include "mediapipe/tasks/cc/components/containers/category.pb.h"
+#include "mediapipe/tasks/cc/components/containers/proto/category.pb.h"
-#include "mediapipe/tasks/cc/components/containers/classifications.pb.h"
+#include "mediapipe/tasks/cc/components/containers/proto/classifications.pb.h"
 #include "mediapipe/tasks/cc/vision/core/running_mode.h"
 #include "mediapipe/tasks/cc/vision/utils/image_utils.h"
 #include "tensorflow/lite/core/api/op_resolver.h"
@@ -44,9 +44,13 @@ limitations under the License.
 namespace mediapipe {
 namespace tasks {
 namespace vision {
+namespace image_classifier {
 namespace {
 
 using ::mediapipe::file::JoinPath;
+using ::mediapipe::tasks::components::containers::proto::ClassificationEntry;
+using ::mediapipe::tasks::components::containers::proto::ClassificationResult;
+using ::mediapipe::tasks::components::containers::proto::Classifications;
 using ::testing::HasSubstr;
 using ::testing::Optional;
 
@@ -814,6 +818,7 @@ TEST_F(LiveStreamModeTest, SucceedsWithRegionOfInterest) {
 }
 
 }  // namespace
+}  // namespace image_classifier
 }  // namespace vision
 }  // namespace tasks
 }  // namespace mediapipe

mediapipe/tasks/cc/vision/image_classifier/proto/BUILD

@@ -19,12 +19,12 @@ package(default_visibility = ["//mediapipe/tasks:internal"])
 licenses(["notice"])
 
 mediapipe_proto_library(
-    name = "image_classifier_options_proto",
+    name = "image_classifier_graph_options_proto",
-    srcs = ["image_classifier_options.proto"],
+    srcs = ["image_classifier_graph_options.proto"],
     deps = [
         "//mediapipe/framework:calculator_options_proto",
         "//mediapipe/framework:calculator_proto",
-        "//mediapipe/tasks/cc/components/proto:classifier_options_proto",
+        "//mediapipe/tasks/cc/components/processors/proto:classifier_options_proto",
         "//mediapipe/tasks/cc/core/proto:base_options_proto",
     ],
 )

mediapipe/tasks/cc/vision/image_classifier/proto/image_classifier_graph_options.proto

@@ -18,12 +18,12 @@ syntax = "proto2";
 package mediapipe.tasks.vision.image_classifier.proto;
 
 import "mediapipe/framework/calculator.proto";
-import "mediapipe/tasks/cc/components/proto/classifier_options.proto";
+import "mediapipe/tasks/cc/components/processors/proto/classifier_options.proto";
 import "mediapipe/tasks/cc/core/proto/base_options.proto";
 
-message ImageClassifierOptions {
+message ImageClassifierGraphOptions {
   extend mediapipe.CalculatorOptions {
-    optional ImageClassifierOptions ext = 456383383;
+    optional ImageClassifierGraphOptions ext = 456383383;
   }
   // Base options for configuring MediaPipe Tasks, such as specifying the TfLite
   // model file with metadata, accelerator options, etc.
@@ -31,5 +31,5 @@ message ImageClassifierOptions {
 
   // Options for configuring the classifier behavior, such as score threshold,
   // number of results, etc.
-  optional components.proto.ClassifierOptions classifier_options = 2;
+  optional components.processors.proto.ClassifierOptions classifier_options = 2;
 }

mediapipe/tasks/cc/vision/image_segmenter/BUILD

@@ -33,7 +33,6 @@ cc_library(
         "//mediapipe/tasks/cc/vision/image_segmenter/proto:image_segmenter_options_cc_proto",
         "@com_google_absl//absl/memory",
         "@com_google_absl//absl/status:statusor",
-        "@org_tensorflow//tensorflow/lite/core/api:op_resolver",
         "@org_tensorflow//tensorflow/lite/kernels:builtin_ops",
     ],
 )
@@ -73,19 +72,4 @@ cc_library(
     alwayslink = 1,
 )
 
-cc_library(
-    name = "image_segmenter_op_resolvers",
-    srcs = ["image_segmenter_op_resolvers.cc"],
-    hdrs = ["image_segmenter_op_resolvers.h"],
-    deps = [
-        "//mediapipe/util/tflite/operations:landmarks_to_transform_matrix",
-        "//mediapipe/util/tflite/operations:max_pool_argmax",
-        "//mediapipe/util/tflite/operations:max_unpooling",
-        "//mediapipe/util/tflite/operations:transform_landmarks",
-        "//mediapipe/util/tflite/operations:transform_tensor_bilinear",
-        "//mediapipe/util/tflite/operations:transpose_conv_bias",
-        "@org_tensorflow//tensorflow/lite/kernels:builtin_ops",
-    ],
-)
-
 # TODO: This test fails in OSS

mediapipe/tasks/cc/vision/image_segmenter/image_segmenter.h

@@ -26,7 +26,6 @@ limitations under the License.
 #include "mediapipe/tasks/cc/core/base_options.h"
 #include "mediapipe/tasks/cc/vision/core/base_vision_task_api.h"
 #include "mediapipe/tasks/cc/vision/image_segmenter/proto/image_segmenter_options.pb.h"
-#include "tensorflow/lite/core/api/op_resolver.h"
 #include "tensorflow/lite/kernels/register.h"
 
 namespace mediapipe {

mediapipe/tasks/cc/vision/image_segmenter/image_segmenter_test.cc

@@ -31,7 +31,6 @@ limitations under the License.
 #include "mediapipe/tasks/cc/components/calculators/tensor/tensors_to_segmentation_calculator.pb.h"
 #include "mediapipe/tasks/cc/core/proto/base_options.pb.h"
 #include "mediapipe/tasks/cc/core/proto/external_file.pb.h"
-#include "mediapipe/tasks/cc/vision/image_segmenter/image_segmenter_op_resolvers.h"
 #include "mediapipe/tasks/cc/vision/image_segmenter/proto/image_segmenter_options.pb.h"
 #include "mediapipe/tasks/cc/vision/utils/image_utils.h"
 #include "tensorflow/lite/core/shims/cc/shims_test_util.h"
@@ -260,8 +259,6 @@ TEST_F(ImageModeTest, SucceedsSelfie128x128Segmentation) {
   auto options = std::make_unique<ImageSegmenterOptions>();
   options->base_options.model_asset_path =
       JoinPath("./", kTestDataDirectory, kSelfie128x128WithMetadata);
-  options->base_options.op_resolver =
-      absl::make_unique<SelfieSegmentationModelOpResolver>();
   options->output_type = ImageSegmenterOptions::OutputType::CONFIDENCE_MASK;
   options->activation = ImageSegmenterOptions::Activation::SOFTMAX;
 
@@ -290,8 +287,6 @@ TEST_F(ImageModeTest, SucceedsSelfie144x256Segmentations) {
   auto options = std::make_unique<ImageSegmenterOptions>();
   options->base_options.model_asset_path =
       JoinPath("./", kTestDataDirectory, kSelfie144x256WithMetadata);
-  options->base_options.op_resolver =
-      absl::make_unique<SelfieSegmentationModelOpResolver>();
   options->output_type = ImageSegmenterOptions::OutputType::CONFIDENCE_MASK;
   options->activation = ImageSegmenterOptions::Activation::NONE;
   MP_ASSERT_OK_AND_ASSIGN(std::unique_ptr<ImageSegmenter> segmenter,

mediapipe/tasks/java/com/google/mediapipe/tasks/components/containers/BUILD

@@ -11,3 +11,26 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+
+package(default_visibility = ["//mediapipe/tasks:internal"])
+
+licenses(["notice"])
+
+android_library(
+    name = "category",
+    srcs = ["Category.java"],
+    deps = [
+        "//third_party:autovalue",
+        "@maven//:com_google_guava_guava",
+    ],
+)
+
+android_library(
+    name = "detection",
+    srcs = ["Detection.java"],
+    deps = [
+        ":category",
+        "//third_party:autovalue",
+        "@maven//:com_google_guava_guava",
+    ],
+)

mediapipe/tasks/java/com/google/mediapipe/tasks/components/containers/Category.java

@@ -0,0 +1,86 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.components.containers;
+
+import com.google.auto.value.AutoValue;
+import java.util.Objects;
+
+/**
+ * Category is a util class, contains a category name, its display name, a float value as score, and
+ * the index of the label in the corresponding label file. Typically it's used as result of
+ * classification or detection tasks.
+ */
+@AutoValue
+public abstract class Category {
+  private static final float TOLERANCE = 1e-6f;
+
+  /**
+   * Creates a {@link Category} instance.
+   *
+   * @param score the probability score of this label category.
+   * @param index the index of the label in the corresponding label file.
+   * @param categoryName the label of this category object.
+   * @param displayName the display name of the label.
+   */
+  public static Category create(float score, int index, String categoryName, String displayName) {
+    return new AutoValue_Category(score, index, categoryName, displayName);
+  }
+
+  /** The probability score of this label category. */
+  public abstract float score();
+
+  /** The index of the label in the corresponding label file. Returns -1 if the index is not set. */
+  public abstract int index();
+
+  /** The label of this category object. */
+  public abstract String categoryName();
+
+  /**
+   * The display name of the label, which may be translated for different locales. For example, a
+   * label, "apple", may be translated into Spanish for display purpose, so that the display name is
+   * "manzana".
+   */
+  public abstract String displayName();
+
+  @Override
+  public final boolean equals(Object o) {
+    if (!(o instanceof Category)) {
+      return false;
+    }
+    Category other = (Category) o;
+    return Math.abs(other.score() - this.score()) < TOLERANCE
+        && other.index() == this.index()
+        && other.categoryName().equals(this.categoryName())
+        && other.displayName().equals(this.displayName());
+  }
+
+  @Override
+  public final int hashCode() {
+    return Objects.hash(categoryName(), displayName(), score(), index());
+  }
+
+  @Override
+  public final String toString() {
+    return "<Category \""
+        + categoryName()
+        + "\" (displayName="
+        + displayName()
+        + " score="
+        + score()
+        + " index="
+        + index()
+        + ")>";
+  }
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/components/containers/Detection.java

@@ -0,0 +1,50 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.components.containers;
+
+import android.graphics.RectF;
+import com.google.auto.value.AutoValue;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * Represents one detected object in the results of {@link
+ * com.google.mediapipe.tasks.version.objectdetector.ObjectDetector}.
+ */
+@AutoValue
+public abstract class Detection {
+
+  /**
+   * Creates a {@link Detection} instance from a list of {@link Category} and a bounding box.
+   *
+   * @param categories a list of {@link Category} objects that contain category name, display name,
+   *     score, and the label index.
+   * @param boundingBox a {@link RectF} object to represent the bounding box.
+   */
+  public static Detection create(List<Category> categories, RectF boundingBox) {
+
+    // As an open source project, we've been trying avoiding depending on common java libraries,
+    // such as Guava, because it may introduce conflicts with clients who also happen to use those
+    // libraries. Therefore, instead of using ImmutableList here, we convert the List into
+    // unmodifiableList
+    return new AutoValue_Detection(Collections.unmodifiableList(categories), boundingBox);
+  }
+
+  /** A list of {@link Category} objects. */
+  public abstract List<Category> categories();
+
+  /** A {@link RectF} object to represent the bounding box of the detected object. */
+  public abstract RectF boundingBox();
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/BUILD

@@ -11,3 +11,27 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+
+package(default_visibility = ["//mediapipe/tasks:internal"])
+
+android_library(
+    name = "core",
+    srcs = glob(["*.java"]),
+    javacopts = [
+        "-Xep:AndroidJdkLibsChecker:OFF",
+    ],
+    deps = [
+        "//mediapipe/calculators/core:flow_limiter_calculator_java_proto_lite",
+        "//mediapipe/calculators/tensor:inference_calculator_java_proto_lite",
+        "//mediapipe/framework:calculator_java_proto_lite",
+        "//mediapipe/framework:calculator_options_java_proto_lite",
+        "//mediapipe/java/com/google/mediapipe/framework:android_framework",
+        "//mediapipe/tasks/cc/core/proto:acceleration_java_proto_lite",
+        "//mediapipe/tasks/cc/core/proto:base_options_java_proto_lite",
+        "//mediapipe/tasks/cc/core/proto:external_file_java_proto_lite",
+        "//mediapipe/tasks/java/com/google/mediapipe/tasks/core/jni:model_resources_cache_jni",
+        "//third_party:autovalue",
+        "@com_google_protobuf//:protobuf_javalite",
+        "@maven//:com_google_guava_guava",
+    ],
+)

mediapipe/tasks/java/com/google/mediapipe/tasks/core/BaseOptions.java

@@ -0,0 +1,96 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.core;
+
+import com.google.auto.value.AutoValue;
+import java.nio.ByteBuffer;
+import java.nio.MappedByteBuffer;
+import java.util.Optional;
+
+/** Options to configure MediaPipe Tasks in general. */
+@AutoValue
+public abstract class BaseOptions {
+  /** Builder for {@link BaseOptions}. */
+  @AutoValue.Builder
+  public abstract static class Builder {
+    /**
+     * Sets the model path to a tflite model with metadata in the assets.
+     *
+     * <p>Note: when model path is set, both model file descriptor and model buffer should be empty.
+     */
+    public abstract Builder setModelAssetPath(String value);
+
+    /**
+     * Sets the native fd int of a tflite model with metadata.
+     *
+     * <p>Note: when model file descriptor is set, both model path and model buffer should be empty.
+     */
+    public abstract Builder setModelAssetFileDescriptor(Integer value);
+
+    /**
+     * Sets either the direct {@link ByteBuffer} or the {@link MappedByteBuffer} of a tflite model
+     * with metadata.
+     *
+     * <p>Note: when model buffer is set, both model file and model file descriptor should be empty.
+     */
+    public abstract Builder setModelAssetBuffer(ByteBuffer value);
+
+    /**
+     * Sets device Delegate to run the MediaPipe pipeline. If the delegate is not set, default
+     * delegate CPU is used.
+     */
+    public abstract Builder setDelegate(Delegate delegate);
+
+    abstract BaseOptions autoBuild();
+
+    /**
+     * Validates and builds the {@link BaseOptions} instance.
+     *
+     * @throws IllegalArgumentException if {@link BaseOptions} is invalid, or the provided model
+     *     buffer is not a direct {@link ByteBuffer} or a {@link MappedByteBuffer}.
+     */
+    public final BaseOptions build() {
+      BaseOptions options = autoBuild();
+      int modelAssetPathPresent = options.modelAssetPath().isPresent() ? 1 : 0;
+      int modelAssetFileDescriptorPresent = options.modelAssetFileDescriptor().isPresent() ? 1 : 0;
+      int modelAssetBufferPresent = options.modelAssetBuffer().isPresent() ? 1 : 0;
+
+      if (modelAssetPathPresent + modelAssetFileDescriptorPresent + modelAssetBufferPresent != 1) {
+        throw new IllegalArgumentException(
+            "Please specify only one of the model asset path, the model asset file descriptor, and"
+                + " the model asset buffer.");
+      }
+      if (options.modelAssetBuffer().isPresent()
+          && !(options.modelAssetBuffer().get().isDirect()
+              || options.modelAssetBuffer().get() instanceof MappedByteBuffer)) {
+        throw new IllegalArgumentException(
+            "The model buffer should be either a direct ByteBuffer or a MappedByteBuffer.");
+      }
+      return options;
+    }
+  }
+
+  abstract Optional<String> modelAssetPath();
+
+  abstract Optional<Integer> modelAssetFileDescriptor();
+
+  abstract Optional<ByteBuffer> modelAssetBuffer();
+
+  abstract Delegate delegate();
+
+  public static Builder builder() {
+    return new AutoValue_BaseOptions.Builder().setDelegate(Delegate.CPU);
+  }
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/Delegate.java

@@ -0,0 +1,22 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.core;
+
+/** MediaPipe Tasks delegate. */
+// TODO implement advanced delegate setting.
+public enum Delegate {
+  CPU,
+  GPU,
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/ErrorListener.java

@@ -0,0 +1,20 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.core;
+
+/** Interface for the customizable MediaPipe task error listener. */
+public interface ErrorListener {
+  void onError(RuntimeException e);
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/ModelResourcesCache.java

@@ -0,0 +1,49 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.core;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/** Facilitates creation and destruction of the native ModelResourcesCache. */
+class ModelResourcesCache {
+  private final long nativeHandle;
+  private final AtomicBoolean isHandleValid;
+
+  public ModelResourcesCache() {
+    nativeHandle = nativeCreateModelResourcesCache();
+    isHandleValid = new AtomicBoolean(true);
+  }
+
+  public boolean isHandleValid() {
+    return isHandleValid.get();
+  }
+
+  public long getNativeHandle() {
+    if (isHandleValid.get()) {
+      return nativeHandle;
+    }
+    return 0;
+  }
+
+  public void release() {
+    if (isHandleValid.compareAndSet(true, false)) {
+      nativeReleaseModelResourcesCache(nativeHandle);
+    }
+  }
+
+  private native long nativeCreateModelResourcesCache();
+
+  private native void nativeReleaseModelResourcesCache(long nativeHandle);
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/ModelResourcesCacheService.java

@@ -0,0 +1,29 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.core;
+
+import com.google.mediapipe.framework.GraphService;
+
+/** Java wrapper for graph service of ModelResourcesCacheService. */
+class ModelResourcesCacheService implements GraphService<ModelResourcesCache> {
+  public ModelResourcesCacheService() {}
+
+  @Override
+  public void installServiceObject(long context, ModelResourcesCache object) {
+    nativeInstallServiceObject(context, object.getNativeHandle());
+  }
+
+  public native void nativeInstallServiceObject(long context, long object);
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/OutputHandler.java

@@ -0,0 +1,130 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.core;
+
+import android.util.Log;
+import com.google.mediapipe.framework.MediaPipeException;
+import com.google.mediapipe.framework.Packet;
+import java.util.List;
+
+/** Base class for handling MediaPipe task graph outputs. */
+public class OutputHandler<OutputT extends TaskResult, InputT> {
+  /**
+   * Interface for converting MediaPipe graph output {@link Packet}s to task result object and task
+   * input object.
+   */
+  public interface OutputPacketConverter<OutputT extends TaskResult, InputT> {
+    OutputT convertToTaskResult(List<Packet> packets);
+
+    InputT convertToTaskInput(List<Packet> packets);
+  }
+
+  /** Interface for the customizable MediaPipe task result listener. */
+  public interface ResultListener<OutputT extends TaskResult, InputT> {
+    void run(OutputT result, InputT input);
+  }
+
+  private static final String TAG = "OutputHandler";
+  // A task-specific graph output packet converter that should be implemented per task.
+  private OutputPacketConverter<OutputT, InputT> outputPacketConverter;
+  // The user-defined task result listener.
+  private ResultListener<OutputT, InputT> resultListener;
+  // The user-defined error listener.
+  protected ErrorListener errorListener;
+  // The cached task result for non latency sensitive use cases.
+  protected OutputT cachedTaskResult;
+  // Whether the output handler should react to timestamp-bound changes by outputting empty packets.
+  private boolean handleTimestampBoundChanges = false;
+
+  /**
+   * Sets a callback to be invoked to convert a {@link Packet} list to a task result object and a
+   * task input object.
+   *
+   * @param converter the task-specific {@link OutputPacketConverter} callback.
+   */
+  public void setOutputPacketConverter(OutputPacketConverter<OutputT, InputT> converter) {
+    this.outputPacketConverter = converter;
+  }
+
+  /**
+   * Sets a callback to be invoked when task result objects become available.
+   *
+   * @param listener the user-defined {@link ResultListener} callback.
+   */
+  public void setResultListener(ResultListener<OutputT, InputT> listener) {
+    this.resultListener = listener;
+  }
+
+  /**
+   * Sets a callback to be invoked when exceptions are thrown from the task graph.
+   *
+   * @param listener The user-defined {@link ErrorListener} callback.
+   */
+  public void setErrorListener(ErrorListener listener) {
+    this.errorListener = listener;
+  }
+
+  /**
+   * Sets whether the output handler should react to the timestamp bound changes that are reprsented
+   * as empty output {@link Packet}s.
+   *
+   * @param handleTimestampBoundChanges A boolean value.
+   */
+  public void setHandleTimestampBoundChanges(boolean handleTimestampBoundChanges) {
+    this.handleTimestampBoundChanges = handleTimestampBoundChanges;
+  }
+
+  /** Returns true if the task graph is set to handle timestamp bound changes. */
+  boolean handleTimestampBoundChanges() {
+    return handleTimestampBoundChanges;
+  }
+
+  /* Returns the cached task result object. */
+  public OutputT retrieveCachedTaskResult() {
+    OutputT taskResult = cachedTaskResult;
+    cachedTaskResult = null;
+    return taskResult;
+  }
+
+  /**
+   * Handles a list of output {@link Packet}s. Invoked when a packet list become available.
+   *
+   * @param packets A list of output {@link Packet}s.
+   */
+  void run(List<Packet> packets) {
+    OutputT taskResult = null;
+    try {
+      taskResult = outputPacketConverter.convertToTaskResult(packets);
+      if (resultListener == null) {
+        cachedTaskResult = taskResult;
+      } else {
+        InputT taskInput = outputPacketConverter.convertToTaskInput(packets);
+        resultListener.run(taskResult, taskInput);
+      }
+    } catch (MediaPipeException e) {
+      if (errorListener != null) {
+        errorListener.onError(e);
+      } else {
+        Log.e(TAG, "Error occurs when getting MediaPipe vision task result. " + e);
+      }
+    } finally {
+      for (Packet packet : packets) {
+        if (packet != null) {
+          packet.release();
+        }
+      }
+    }
+  }
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/TaskInfo.java

@@ -0,0 +1,156 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.core;
+
+import com.google.auto.value.AutoValue;
+import com.google.mediapipe.proto.CalculatorOptionsProto.CalculatorOptions;
+import com.google.mediapipe.proto.CalculatorProto.CalculatorGraphConfig;
+import com.google.mediapipe.proto.CalculatorProto.CalculatorGraphConfig.Node;
+import com.google.mediapipe.proto.CalculatorProto.InputStreamInfo;
+import com.google.mediapipe.calculator.proto.FlowLimiterCalculatorProto.FlowLimiterCalculatorOptions;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * {@link TaskInfo} contains all needed informaton to initialize a MediaPipe Task {@link
+ * com.google.mediapipe.framework.Graph}.
+ */
+@AutoValue
+public abstract class TaskInfo<T extends TaskOptions> {
+  /** Builder for {@link TaskInfo}. */
+  @AutoValue.Builder
+  public abstract static class Builder<T extends TaskOptions> {
+    /** Sets the MediaPipe task graph name. */
+    public abstract Builder<T> setTaskGraphName(String value);
+
+    /** Sets a list of task graph input stream info {@link String}s in the form TAG:name. */
+    public abstract Builder<T> setInputStreams(List<String> value);
+
+    /** Sets a list of task graph output stream info {@link String}s in the form TAG:name. */
+    public abstract Builder<T> setOutputStreams(List<String> value);
+
+    /** Sets to true if the task requires a flow limiter. */
+    public abstract Builder<T> setEnableFlowLimiting(Boolean value);
+
+    /**
+     * Sets a task-specific options instance.
+     *
+     * @param value a task-specific options that is derived from {@link TaskOptions}.
+     */
+    public abstract Builder<T> setTaskOptions(T value);
+
+    public abstract TaskInfo<T> autoBuild();
+
+    /**
+     * Validates and builds the {@link TaskInfo} instance. *
+     *
+     * @throws IllegalArgumentException if the required information such as task graph name, graph
+     *     input streams, and the graph output streams are empty.
+     */
+    public final TaskInfo<T> build() {
+      TaskInfo<T> taskInfo = autoBuild();
+      if (taskInfo.taskGraphName().isEmpty()
+          || taskInfo.inputStreams().isEmpty()
+          || taskInfo.outputStreams().isEmpty()) {
+        throw new IllegalArgumentException(
+            "Task graph's name, input streams, and output streams should be non-empty.");
+      }
+      return taskInfo;
+    }
+  }
+
+  abstract String taskGraphName();
+
+  abstract T taskOptions();
+
+  abstract List<String> inputStreams();
+
+  abstract List<String> outputStreams();
+
+  abstract Boolean enableFlowLimiting();
+
+  public static <T extends TaskOptions> Builder<T> builder() {
+    return new AutoValue_TaskInfo.Builder<T>();
+  }
+
+  /* Returns a list of the output stream names without the stream tags. */
+  List<String> outputStreamNames() {
+    List<String> streamNames = new ArrayList<>(outputStreams().size());
+    for (String stream : outputStreams()) {
+      streamNames.add(stream.substring(stream.lastIndexOf(':') + 1));
+    }
+    return streamNames;
+  }
+
+  /**
+   * Creates a MediaPipe Task {@link CalculatorGraphConfig} protobuf message from the {@link
+   * TaskInfo} instance.
+   */
+  CalculatorGraphConfig generateGraphConfig() {
+    CalculatorGraphConfig.Builder graphBuilder = CalculatorGraphConfig.newBuilder();
+    Node.Builder taskSubgraphBuilder =
+        Node.newBuilder()
+            .setCalculator(taskGraphName())
+            .setOptions(taskOptions().convertToCalculatorOptionsProto());
+    for (String outputStream : outputStreams()) {
+      taskSubgraphBuilder.addOutputStream(outputStream);
+      graphBuilder.addOutputStream(outputStream);
+    }
+    if (!enableFlowLimiting()) {
+      for (String inputStream : inputStreams()) {
+        taskSubgraphBuilder.addInputStream(inputStream);
+        graphBuilder.addInputStream(inputStream);
+      }
+      graphBuilder.addNode(taskSubgraphBuilder.build());
+      return graphBuilder.build();
+    }
+    Node.Builder flowLimiterCalculatorBuilder =
+        Node.newBuilder()
+            .setCalculator("FlowLimiterCalculator")
+            .addInputStreamInfo(
+                InputStreamInfo.newBuilder().setTagIndex("FINISHED").setBackEdge(true).build())
+            .setOptions(
+                CalculatorOptions.newBuilder()
+                    .setExtension(
+                        FlowLimiterCalculatorOptions.ext,
+                        FlowLimiterCalculatorOptions.newBuilder()
+                            .setMaxInFlight(1)
+                            .setMaxInQueue(1)
+                            .build())
+                    .build());
+    for (String inputStream : inputStreams()) {
+      graphBuilder.addInputStream(inputStream);
+      flowLimiterCalculatorBuilder.addInputStream(stripTagIndex(inputStream));
+      String taskInputStream = addStreamNamePrefix(inputStream);
+      flowLimiterCalculatorBuilder.addOutputStream(stripTagIndex(taskInputStream));
+      taskSubgraphBuilder.addInputStream(taskInputStream);
+    }
+    flowLimiterCalculatorBuilder.addInputStream(
+        "FINISHED:" + stripTagIndex(outputStreams().get(0)));
+    graphBuilder.addNode(flowLimiterCalculatorBuilder.build());
+    graphBuilder.addNode(taskSubgraphBuilder.build());
+    return graphBuilder.build();
+  }
+
+  private String stripTagIndex(String tagIndexName) {
+    return tagIndexName.substring(tagIndexName.lastIndexOf(':') + 1);
+  }
+
+  private String addStreamNamePrefix(String tagIndexName) {
+    return tagIndexName.substring(0, tagIndexName.lastIndexOf(':') + 1)
+        + "throttled_"
+        + stripTagIndex(tagIndexName);
+  }
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/TaskOptions.java

@@ -0,0 +1,75 @@
+/* Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+==============================================================================*/
+
+package com.google.mediapipe.tasks.core;
+
+import com.google.mediapipe.calculator.proto.InferenceCalculatorProto;
+import com.google.mediapipe.proto.CalculatorOptionsProto.CalculatorOptions;
+import com.google.mediapipe.tasks.core.proto.AccelerationProto;
+import com.google.mediapipe.tasks.core.proto.BaseOptionsProto;
+import com.google.mediapipe.tasks.core.proto.ExternalFileProto;
+import com.google.protobuf.ByteString;
+
+/**
+ * MediaPipe Tasks options base class. Any MediaPipe task-specific options class should extend
+ * {@link TaskOptions}.
+ */
+public abstract class TaskOptions {
+  /**
+   * Converts a MediaPipe Tasks task-specific options to a {@link CalculatorOptions} protobuf
+   * message.
+   */
+  public abstract CalculatorOptions convertToCalculatorOptionsProto();
+
+  /**
+   * Converts a {@link BaseOptions} instance to a {@link BaseOptionsProto.BaseOptions} protobuf
+   * message.
+   */
+  protected BaseOptionsProto.BaseOptions convertBaseOptionsToProto(BaseOptions options) {
+    ExternalFileProto.ExternalFile.Builder externalFileBuilder =
+        ExternalFileProto.ExternalFile.newBuilder();
+    options.modelAssetPath().ifPresent(externalFileBuilder::setFileName);
+    options
+        .modelAssetFileDescriptor()
+        .ifPresent(
+            fd ->
+                externalFileBuilder.setFileDescriptorMeta(
+                    ExternalFileProto.FileDescriptorMeta.newBuilder().setFd(fd).build()));
+    options
+        .modelAssetBuffer()
+        .ifPresent(
+            modelBuffer -> {
+              modelBuffer.rewind();
+              externalFileBuilder.setFileContent(ByteString.copyFrom(modelBuffer));
+            });
+    AccelerationProto.Acceleration.Builder accelerationBuilder =
+        AccelerationProto.Acceleration.newBuilder();
+    switch (options.delegate()) {
+      case CPU:
+        accelerationBuilder.setXnnpack(
+            InferenceCalculatorProto.InferenceCalculatorOptions.Delegate.Xnnpack
+                .getDefaultInstance());
+        break;
+      case GPU:
+        accelerationBuilder.setGpu(
+            InferenceCalculatorProto.InferenceCalculatorOptions.Delegate.Gpu.getDefaultInstance());
+        break;
+    }
+    return BaseOptionsProto.BaseOptions.newBuilder()
+        .setModelAsset(externalFileBuilder.build())
+        .setAcceleration(accelerationBuilder.build())
+        .build();
+  }
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/TaskResult.java

@@ -0,0 +1,24 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.core;
+
+/**
+ * Interface for the MediaPipe Task result. Any MediaPipe task-specific result class should
+ * implement {@link TaskResult}.
+ */
+public interface TaskResult {
+  /** Returns the timestamp that is associated with the task result object. */
+  long timestampMs();
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/TaskRunner.java

@@ -0,0 +1,265 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.core;
+
+import android.content.Context;
+import android.util.Log;
+import com.google.mediapipe.framework.AndroidAssetUtil;
+import com.google.mediapipe.framework.AndroidPacketCreator;
+import com.google.mediapipe.framework.Graph;
+import com.google.mediapipe.framework.MediaPipeException;
+import com.google.mediapipe.framework.Packet;
+import java.util.Map;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/** The runner of MediaPipe task graphs. */
+public class TaskRunner implements AutoCloseable {
+  private static final String TAG = TaskRunner.class.getSimpleName();
+  private static final long TIMESATMP_UNITS_PER_SECOND = 1000000;
+
+  private final OutputHandler<? extends TaskResult, ?> outputHandler;
+  private final AtomicBoolean graphStarted = new AtomicBoolean(false);
+  private final Graph graph;
+  private final ModelResourcesCache modelResourcesCache;
+  private final AndroidPacketCreator packetCreator;
+  private long lastSeenTimestamp = Long.MIN_VALUE;
+  private ErrorListener errorListener;
+
+  /**
+   * Create a {@link TaskRunner} instance.
+   *
+   * @param context an Android {@link Context}.
+   * @param taskInfo a {@link TaskInfo} instance contains task graph name, task options, and graph
+   *     input and output stream names.
+   * @param outputHandler a {@link OutputHandler} instance handles task result object and runtime
+   *     exception.
+   * @throws MediaPipeException for any error during {@link TaskRunner} creation.
+   */
+  public static TaskRunner create(
+      Context context,
+      TaskInfo<? extends TaskOptions> taskInfo,
+      OutputHandler<? extends TaskResult, ?> outputHandler) {
+    AndroidAssetUtil.initializeNativeAssetManager(context);
+    Graph mediapipeGraph = new Graph();
+    mediapipeGraph.loadBinaryGraph(taskInfo.generateGraphConfig());
+    ModelResourcesCache graphModelResourcesCache = new ModelResourcesCache();
+    mediapipeGraph.setServiceObject(new ModelResourcesCacheService(), graphModelResourcesCache);
+    mediapipeGraph.addMultiStreamCallback(
+        taskInfo.outputStreamNames(),
+        outputHandler::run,
+        /*observeTimestampBounds=*/ outputHandler.handleTimestampBoundChanges());
+    mediapipeGraph.startRunningGraph();
+    // Waits until all calculators are opened and the graph is fully started.
+    mediapipeGraph.waitUntilGraphIdle();
+    return new TaskRunner(mediapipeGraph, graphModelResourcesCache, outputHandler);
+  }
+
+  /**
+   * Sets a callback to be invoked when exceptions are thrown by the {@link TaskRunner} instance.
+   *
+   * @param listener an {@link ErrorListener} callback.
+   */
+  public void setErrorListener(ErrorListener listener) {
+    this.errorListener = listener;
+  }
+
+  /** Returns the {@link AndroidPacketCreator} associated to the {@link TaskRunner} instance. */
+  public AndroidPacketCreator getPacketCreator() {
+    return packetCreator;
+  }
+
+  /**
+   * A synchronous method for processing batch data.
+   *
+   * <p>Note: This method is designed for processing batch data such as unrelated images and texts.
+   * The call blocks the current thread until a failure status or a successful result is returned.
+   * An internal timestamp will be assigend per invocation. This method is thread-safe and allows
+   * clients to call it from different threads.
+   *
+   * @param inputs a map contains (input stream {@link String}, data {@link Packet}) pairs.
+   */
+  public synchronized TaskResult process(Map<String, Packet> inputs) {
+    addPackets(inputs, generateSyntheticTimestamp());
+    graph.waitUntilGraphIdle();
+    return outputHandler.retrieveCachedTaskResult();
+  }
+
+  /**
+   * A synchronous method for processing offline streaming data.
+   *
+   * <p>Note: This method is designed for processing offline streaming data such as the decoded
+   * frames from a video file and an audio file. The call blocks the current thread until a failure
+   * status or a successful result is returned. The caller must ensure that the input timestamp is
+   * greater than the timestamps of previous invocations. This method is thread-unsafe and it is the
+   * caller's responsibility to synchronize access to this method across multiple threads and to
+   * ensure that the input packet timestamps are in order.
+   *
+   * @param inputs a map contains (input stream {@link String}, data {@link Packet}) pairs.
+   * @param inputTimestamp the timestamp of the input packets.
+   */
+  public synchronized TaskResult process(Map<String, Packet> inputs, long inputTimestamp) {
+    validateInputTimstamp(inputTimestamp);
+    addPackets(inputs, inputTimestamp);
+    graph.waitUntilGraphIdle();
+    return outputHandler.retrieveCachedTaskResult();
+  }
+
+  /**
+   * An asynchronous method for handling live streaming data.
+   *
+   * <p>Note: This method that is designed for handling live streaming data such as live camera and
+   * microphone data. A user-defined packets callback function must be provided in the constructor
+   * to receive the output packets. The caller must ensure that the input packet timestamps are
+   * monotonically increasing. This method is thread-unsafe and it is the caller's responsibility to
+   * synchronize access to this method across multiple threads and to ensure that the input packet
+   * timestamps are in order.
+   *
+   * @param inputs a map contains (input stream {@link String}, data {@link Packet}) pairs.
+   * @param inputTimestamp the timestamp of the input packets.
+   */
+  public synchronized void send(Map<String, Packet> inputs, long inputTimestamp) {
+    validateInputTimstamp(inputTimestamp);
+    addPackets(inputs, inputTimestamp);
+  }
+
+  /**
+   * Resets and restarts the {@link TaskRunner} instance. This can be useful for resetting a
+   * stateful task graph to process new data.
+   */
+  public void restart() {
+    if (graphStarted.get()) {
+      try {
+        graphStarted.set(false);
+        graph.closeAllPacketSources();
+        graph.waitUntilGraphDone();
+      } catch (MediaPipeException e) {
+        reportError(e);
+      }
+    }
+    try {
+      graph.startRunningGraph();
+      // Waits until all calculators are opened and the graph is fully restarted.
+      graph.waitUntilGraphIdle();
+      graphStarted.set(true);
+    } catch (MediaPipeException e) {
+      reportError(e);
+    }
+  }
+
+  /** Closes and cleans up the {@link TaskRunner} instance. */
+  @Override
+  public void close() {
+    if (!graphStarted.get()) {
+      return;
+    }
+    try {
+      graphStarted.set(false);
+      graph.closeAllPacketSources();
+      graph.waitUntilGraphDone();
+      if (modelResourcesCache != null) {
+        modelResourcesCache.release();
+      }
+    } catch (MediaPipeException e) {
+      // Note: errors during Process are reported at the earliest opportunity,
+      // which may be addPacket or waitUntilDone, depending on timing. For consistency,
+      // we want to always report them using the same async handler if installed.
+      reportError(e);
+    }
+    try {
+      graph.tearDown();
+    } catch (MediaPipeException e) {
+      reportError(e);
+    }
+  }
+
+  private synchronized void addPackets(Map<String, Packet> inputs, long inputTimestamp) {
+    if (!graphStarted.get()) {
+      reportError(
+          new MediaPipeException(
+              MediaPipeException.StatusCode.FAILED_PRECONDITION.ordinal(),
+              "The task graph hasn't been successfully started or error occurs during graph"
+                  + " initializaton."));
+    }
+    try {
+      for (Map.Entry<String, Packet> entry : inputs.entrySet()) {
+        // addConsumablePacketToInputStream allows the graph to take exclusive ownership of the
+        // packet, which may allow for more memory optimizations.
+        graph.addConsumablePacketToInputStream(entry.getKey(), entry.getValue(), inputTimestamp);
+        // If addConsumablePacket succeeded, we don't need to release the packet ourselves.
+        entry.setValue(null);
+      }
+    } catch (MediaPipeException e) {
+      // TODO: do not suppress exceptions here!
+      if (errorListener == null) {
+        Log.e(TAG, "Mediapipe error: ", e);
+      } else {
+        throw e;
+      }
+    } finally {
+      for (Packet packet : inputs.values()) {
+        // In case of error, addConsumablePacketToInputStream will not release the packet, so we
+        // have to release it ourselves.
+        if (packet != null) {
+          packet.release();
+        }
+      }
+    }
+  }
+
+  /**
+   * Checks if the input timestamp is strictly greater than the last timestamp that has been
+   * processed.
+   *
+   * @param inputTimestamp the input timestamp.
+   */
+  private void validateInputTimstamp(long inputTimestamp) {
+    if (lastSeenTimestamp >= inputTimestamp) {
+      reportError(
+          new MediaPipeException(
+              MediaPipeException.StatusCode.FAILED_PRECONDITION.ordinal(),
+              "The received packets having a smaller timestamp than the processed timestamp."));
+    }
+    lastSeenTimestamp = inputTimestamp;
+  }
+
+  /** Generates a synthetic input timestamp in the batch processing mode. */
+  private long generateSyntheticTimestamp() {
+    long timestamp =
+        lastSeenTimestamp == Long.MIN_VALUE ? 0 : lastSeenTimestamp + TIMESATMP_UNITS_PER_SECOND;
+    lastSeenTimestamp = timestamp;
+    return timestamp;
+  }
+
+  /** Private constructor. */
+  private TaskRunner(
+      Graph graph,
+      ModelResourcesCache modelResourcesCache,
+      OutputHandler<? extends TaskResult, ?> outputHandler) {
+    this.outputHandler = outputHandler;
+    this.graph = graph;
+    this.modelResourcesCache = modelResourcesCache;
+    this.packetCreator = new AndroidPacketCreator(graph);
+    graphStarted.set(true);
+  }
+
+  /** Reports error. */
+  private void reportError(MediaPipeException e) {
+    if (errorListener != null) {
+      errorListener.onError(e);
+    } else {
+      throw e;
+    }
+  }
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/jni/BUILD

@@ -0,0 +1,41 @@
+# Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+load("@org_tensorflow//tensorflow/lite/core/shims:cc_library_with_tflite.bzl", "cc_library_with_tflite")
+
+package(default_visibility = ["//mediapipe/tasks:internal"])
+
+licenses(["notice"])
+
+cc_library_with_tflite(
+    name = "model_resources_cache_jni",
+    srcs = [
+        "model_resources_cache_jni.cc",
+    ],
+    hdrs = [
+        "model_resources_cache_jni.h",
+    ],
+    tflite_deps = [
+        "//mediapipe/tasks/cc/core:model_resources_cache",
+        "@org_tensorflow//tensorflow/lite/core/shims:builtin_ops",
+    ],
+    deps = [
+        "//mediapipe/java/com/google/mediapipe/framework/jni:mediapipe_framework_jni",
+        "//mediapipe/tasks/cc/core:mediapipe_builtin_op_resolver",
+    ] + select({
+        "//conditions:default": ["//third_party/java/jdk:jni"],
+        "//mediapipe:android": [],
+    }),
+    alwayslink = 1,
+)

mediapipe/tasks/java/com/google/mediapipe/tasks/core/jni/BUILD.bazel

@@ -0,0 +1,72 @@
+# Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+load("@org_tensorflow//tensorflow/lite/core/shims:cc_library_with_tflite.bzl", "cc_library_with_tflite")
+
+package(default_visibility = ["//mediapipe/tasks:internal"])
+
+cc_library_with_tflite(
+    name = "model_resources_cache_jni",
+    srcs = [
+        "model_resources_cache_jni.cc",
+    ],
+    hdrs = [
+        "model_resources_cache_jni.h",
+    ] + select({
+        # The Android toolchain makes "jni.h" available in the include path.
+        # For non-Android toolchains, generate jni.h and jni_md.h.
+        "//mediapipe:android": [],
+        "//conditions:default": [
+            ":jni.h",
+            ":jni_md.h",
+        ],
+    }),
+    tflite_deps = [
+        "//mediapipe/tasks/cc/core:model_resources_cache",
+    ],
+    deps = [
+        "//mediapipe/java/com/google/mediapipe/framework/jni:mediapipe_framework_jni",
+        "//mediapipe/tasks/cc/core:mediapipe_builtin_op_resolver",
+    ] + select({
+        "//conditions:default": [],
+        "//mediapipe:android": [],
+    }),
+    alwayslink = 1,
+)
+
+# Silly rules to make
+# #include <jni.h>
+# in the source headers work
+# (in combination with the "includes" attribute of the tf_cuda_library rule
+# above. Not needed when using the Android toolchain).
+#
+# Inspired from:
+# https://github.com/bazelbuild/bazel/blob/f99a0543f8d97339d32075c7176b79f35be84606/src/main/native/BUILD
+# but hopefully there is a simpler alternative to this.
+genrule(
+    name = "copy_jni_h",
+    srcs = ["@bazel_tools//tools/jdk:jni_header"],
+    outs = ["jni.h"],
+    cmd = "cp -f $< $@",
+)
+
+genrule(
+    name = "copy_jni_md_h",
+    srcs = select({
+        "//mediapipe:macos": ["@bazel_tools//tools/jdk:jni_md_header-darwin"],
+        "//conditions:default": ["@bazel_tools//tools/jdk:jni_md_header-linux"],
+    }),
+    outs = ["jni_md.h"],
+    cmd = "cp -f $< $@",
+)

mediapipe/tasks/java/com/google/mediapipe/tasks/core/jni/model_resources_cache_jni.cc

@@ -0,0 +1,51 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "mediapipe/tasks/java/com/google/mediapipe/tasks/core/jni/model_resources_cache_jni.h"
+
+#include <utility>
+
+#include "mediapipe/java/com/google/mediapipe/framework/jni/graph_service_jni.h"
+#include "mediapipe/tasks/cc/core/mediapipe_builtin_op_resolver.h"
+#include "mediapipe/tasks/cc/core/model_resources_cache.h"
+#include "tensorflow/lite/core/shims/cc/kernels/register.h"
+
+namespace {
+using ::mediapipe::tasks::core::kModelResourcesCacheService;
+using ::mediapipe::tasks::core::MediaPipeBuiltinOpResolver;
+using ::mediapipe::tasks::core::ModelResourcesCache;
+using HandleType = std::shared_ptr<ModelResourcesCache>*;
+}  // namespace
+
+JNIEXPORT jlong JNICALL MODEL_RESOURCES_CACHE_METHOD(
+    nativeCreateModelResourcesCache)(JNIEnv* env, jobject thiz) {
+  auto ptr = std::make_shared<ModelResourcesCache>(
+      absl::make_unique<MediaPipeBuiltinOpResolver>());
+  HandleType handle = new std::shared_ptr<ModelResourcesCache>(std::move(ptr));
+  return reinterpret_cast<jlong>(handle);
+}
+
+JNIEXPORT void JNICALL MODEL_RESOURCES_CACHE_METHOD(
+    nativeReleaseModelResourcesCache)(JNIEnv* env, jobject thiz,
+                                      jlong nativeHandle) {
+  delete reinterpret_cast<HandleType>(nativeHandle);
+}
+
+JNIEXPORT void JNICALL MODEL_RESOURCES_CACHE_SERVICE_METHOD(
+    nativeInstallServiceObject)(JNIEnv* env, jobject thiz, jlong contextHandle,
+                                jlong objectHandle) {
+  mediapipe::android::GraphServiceHelper::SetServiceObject(
+      contextHandle, kModelResourcesCacheService,
+      *reinterpret_cast<HandleType>(objectHandle));
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/core/jni/model_resources_cache_jni.h

@@ -0,0 +1,45 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef JAVA_COM_GOOGLE_MEDIAPIPE_TASKS_CORE_JNI_MODEL_RESOURCES_CACHE_JNI_H_
+#define JAVA_COM_GOOGLE_MEDIAPIPE_TASKS_CORE_JNI_MODEL_RESOURCES_CACHE_JNI_H_
+
+#include <jni.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif  // __cplusplus
+
+#define MODEL_RESOURCES_CACHE_METHOD(METHOD_NAME) \
+  Java_com_google_mediapipe_tasks_core_ModelResourcesCache_##METHOD_NAME
+
+#define MODEL_RESOURCES_CACHE_SERVICE_METHOD(METHOD_NAME) \
+  Java_com_google_mediapipe_tasks_core_ModelResourcesCacheService_##METHOD_NAME
+
+JNIEXPORT jlong JNICALL MODEL_RESOURCES_CACHE_METHOD(
+    nativeCreateModelResourcesCache)(JNIEnv* env, jobject thiz);
+
+JNIEXPORT void JNICALL MODEL_RESOURCES_CACHE_METHOD(
+    nativeReleaseModelResourcesCache)(JNIEnv* env, jobject thiz,
+                                      jlong nativeHandle);
+
+JNIEXPORT void JNICALL MODEL_RESOURCES_CACHE_SERVICE_METHOD(
+    nativeInstallServiceObject)(JNIEnv* env, jobject thiz, jlong contextHandle,
+                                jlong objectHandle);
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif  // __cplusplus
+
+#endif  // JAVA_COM_GOOGLE_MEDIAPIPE_TASKS_CORE_JNI_MODEL_RESOURCES_CACHE_JNI_H_

mediapipe/tasks/java/com/google/mediapipe/tasks/vision/core/BUILD

@@ -11,3 +11,38 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+
+licenses(["notice"])
+
+package(default_visibility = ["//mediapipe/tasks:internal"])
+
+android_library(
+    name = "core",
+    srcs = glob(["*.java"]),
+    deps = [
+        ":libmediapipe_tasks_vision_jni_lib",
+        "//mediapipe/java/com/google/mediapipe/framework:android_framework_no_mff",
+        "//mediapipe/java/com/google/mediapipe/framework/image",
+        "//mediapipe/tasks/java/com/google/mediapipe/tasks/core",
+        "@maven//:com_google_guava_guava",
+    ],
+)
+
+# The native library of all MediaPipe vision tasks.
+cc_binary(
+    name = "libmediapipe_tasks_vision_jni.so",
+    linkshared = 1,
+    linkstatic = 1,
+    deps = [
+        "//mediapipe/calculators/core:flow_limiter_calculator",
+        "//mediapipe/java/com/google/mediapipe/framework/jni:mediapipe_framework_jni",
+        "//mediapipe/tasks/cc/vision/object_detector:object_detector_graph",
+        "//mediapipe/tasks/java/com/google/mediapipe/tasks/core/jni:model_resources_cache_jni",
+    ],
+)
+
+cc_library(
+    name = "libmediapipe_tasks_vision_jni_lib",
+    srcs = [":libmediapipe_tasks_vision_jni.so"],
+    alwayslink = 1,
+)

mediapipe/tasks/java/com/google/mediapipe/tasks/vision/core/BaseVisionTaskApi.java

@@ -0,0 +1,114 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.vision.core;
+
+import com.google.mediapipe.framework.MediaPipeException;
+import com.google.mediapipe.framework.Packet;
+import com.google.mediapipe.framework.image.Image;
+import com.google.mediapipe.tasks.core.TaskResult;
+import com.google.mediapipe.tasks.core.TaskRunner;
+import java.util.HashMap;
+import java.util.Map;
+
+/** The base class of MediaPipe vision tasks. */
+public class BaseVisionTaskApi implements AutoCloseable {
+  private static final long MICROSECONDS_PER_MILLISECOND = 1000;
+  private final TaskRunner runner;
+  private final RunningMode runningMode;
+
+  static {
+    System.loadLibrary("mediapipe_tasks_vision_jni");
+  }
+
+  /**
+   * Constructor to initialize an {@link BaseVisionTaskApi} from a {@link TaskRunner} and a vision
+   * task {@link RunningMode}.
+   *
+   * @param runner a {@link TaskRunner}.
+   * @param runningMode a mediapipe vision task {@link RunningMode}.
+   */
+  public BaseVisionTaskApi(TaskRunner runner, RunningMode runningMode) {
+    this.runner = runner;
+    this.runningMode = runningMode;
+  }
+
+  /**
+   * A synchronous method to process single image inputs. The call blocks the current thread until a
+   * failure status or a successful result is returned.
+   *
+   * @param imageStreamName the image input stream name.
+   * @param image a MediaPipe {@link Image} object for processing.
+   * @throws MediaPipeException if the task is not in the image mode.
+   */
+  protected TaskResult processImageData(String imageStreamName, Image image) {
+    if (runningMode != RunningMode.IMAGE) {
+      throw new MediaPipeException(
+          MediaPipeException.StatusCode.FAILED_PRECONDITION.ordinal(),
+          "Task is not initialized with the image mode. Current running mode:"
+              + runningMode.name());
+    }
+    Map<String, Packet> inputPackets = new HashMap<>();
+    inputPackets.put(imageStreamName, runner.getPacketCreator().createImage(image));
+    return runner.process(inputPackets);
+  }
+
+  /**
+   * A synchronous method to process continuous video frames. The call blocks the current thread
+   * until a failure status or a successful result is returned.
+   *
+   * @param imageStreamName the image input stream name.
+   * @param image a MediaPipe {@link Image} object for processing.
+   * @param timestampMs the corresponding timestamp of the input image in milliseconds.
+   * @throws MediaPipeException if the task is not in the video mode.
+   */
+  protected TaskResult processVideoData(String imageStreamName, Image image, long timestampMs) {
+    if (runningMode != RunningMode.VIDEO) {
+      throw new MediaPipeException(
+          MediaPipeException.StatusCode.FAILED_PRECONDITION.ordinal(),
+          "Task is not initialized with the video mode. Current running mode:"
+              + runningMode.name());
+    }
+    Map<String, Packet> inputPackets = new HashMap<>();
+    inputPackets.put(imageStreamName, runner.getPacketCreator().createImage(image));
+    return runner.process(inputPackets, timestampMs * MICROSECONDS_PER_MILLISECOND);
+  }
+
+  /**
+   * An asynchronous method to send live stream data to the {@link TaskRunner}. The results will be
+   * available in the user-defined result listener.
+   *
+   * @param imageStreamName the image input stream name.
+   * @param image a MediaPipe {@link Image} object for processing.
+   * @param timestampMs the corresponding timestamp of the input image in milliseconds.
+   * @throws MediaPipeException if the task is not in the video mode.
+   */
+  protected void sendLiveStreamData(String imageStreamName, Image image, long timestampMs) {
+    if (runningMode != RunningMode.LIVE_STREAM) {
+      throw new MediaPipeException(
+          MediaPipeException.StatusCode.FAILED_PRECONDITION.ordinal(),
+          "Task is not initialized with the live stream mode. Current running mode:"
+              + runningMode.name());
+    }
+    Map<String, Packet> inputPackets = new HashMap<>();
+    inputPackets.put(imageStreamName, runner.getPacketCreator().createImage(image));
+    runner.send(inputPackets, timestampMs * MICROSECONDS_PER_MILLISECOND);
+  }
+
+  /** Closes and cleans up the MediaPipe vision task. */
+  @Override
+  public void close() {
+    runner.close();
+  }
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/vision/core/RunningMode.java

@@ -0,0 +1,32 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.vision.core;
+
+/**
+ * MediaPipe vision task running mode. A MediaPipe vision task can be run with three different
+ * modes:
+ *
+ * <ul>
+ *   <li>IMAGE: The mode for running a mediapipe vision task on single image inputs.
+ *   <li>VIDEO: The mode for running a mediapipe vision task on the decoded frames of a video.
+ *   <li>LIVE_STREAM: The mode for running a mediapipe vision task on a live stream of input data,
+ *       such as from camera.
+ * </ul>
+ */
+public enum RunningMode {
+  IMAGE,
+  VIDEO,
+  LIVE_STREAM
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/vision/objectdetector/BUILD

@@ -11,3 +11,34 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+
+package(default_visibility = ["//mediapipe/tasks:internal"])
+
+licenses(["notice"])
+
+android_library(
+    name = "objectdetector",
+    srcs = [
+        "ObjectDetectionResult.java",
+        "ObjectDetector.java",
+    ],
+    javacopts = [
+        "-Xep:AndroidJdkLibsChecker:OFF",
+    ],
+    manifest = ":AndroidManifest.xml",
+    deps = [
+        "//mediapipe/framework:calculator_options_java_proto_lite",
+        "//mediapipe/framework/formats:detection_java_proto_lite",
+        "//mediapipe/framework/formats:location_data_java_proto_lite",
+        "//mediapipe/java/com/google/mediapipe/framework:android_framework",
+        "//mediapipe/java/com/google/mediapipe/framework/image",
+        "//mediapipe/tasks/cc/core/proto:base_options_java_proto_lite",
+        "//mediapipe/tasks/cc/vision/object_detector/proto:object_detector_options_java_proto_lite",
+        "//mediapipe/tasks/java/com/google/mediapipe/tasks/components/containers:category",
+        "//mediapipe/tasks/java/com/google/mediapipe/tasks/components/containers:detection",
+        "//mediapipe/tasks/java/com/google/mediapipe/tasks/core",
+        "//mediapipe/tasks/java/com/google/mediapipe/tasks/vision/core",
+        "//third_party:autovalue",
+        "@maven//:com_google_guava_guava",
+    ],
+)

mediapipe/tasks/java/com/google/mediapipe/tasks/vision/objectdetector/ObjectDetectionResult.java

@@ -0,0 +1,75 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.vision.objectdetector;
+
+import android.graphics.RectF;
+import com.google.auto.value.AutoValue;
+import com.google.mediapipe.tasks.components.containers.Category;
+import com.google.mediapipe.tasks.core.TaskResult;
+import com.google.mediapipe.formats.proto.DetectionProto.Detection;
+import com.google.mediapipe.formats.proto.LocationDataProto.LocationData.BoundingBox;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+/** Represents the detection results generated by {@link ObjectDetector}. */
+@AutoValue
+public abstract class ObjectDetectionResult implements TaskResult {
+  private static final int DEFAULT_CATEGORY_INDEX = -1;
+
+  @Override
+  public abstract long timestampMs();
+
+  public abstract List<com.google.mediapipe.tasks.components.containers.Detection> detections();
+
+  /**
+   * Creates an {@link ObjectDetectionResult} instance from a list of {@link Detection} protobuf
+   * messages.
+   *
+   * @param detectionList a list of {@link Detection} protobuf messages.
+   */
+  static ObjectDetectionResult create(List<Detection> detectionList, long timestampMs) {
+    List<com.google.mediapipe.tasks.components.containers.Detection> detections = new ArrayList<>();
+    for (Detection detectionProto : detectionList) {
+      List<Category> categories = new ArrayList<>();
+      for (int idx = 0; idx < detectionProto.getScoreCount(); ++idx) {
+        categories.add(
+            Category.create(
+                detectionProto.getScore(idx),
+                detectionProto.getLabelIdCount() > idx
+                    ? detectionProto.getLabelId(idx)
+                    : DEFAULT_CATEGORY_INDEX,
+                detectionProto.getLabelCount() > idx ? detectionProto.getLabel(idx) : "",
+                detectionProto.getDisplayNameCount() > idx
+                    ? detectionProto.getDisplayName(idx)
+                    : ""));
+      }
+      RectF boundingBox = new RectF();
+      if (detectionProto.getLocationData().hasBoundingBox()) {
+        BoundingBox boundingBoxProto = detectionProto.getLocationData().getBoundingBox();
+        boundingBox.set(
+            /*left=*/ boundingBoxProto.getXmin(),
+            /*top=*/ boundingBoxProto.getYmin(),
+            /*right=*/ boundingBoxProto.getXmin() + boundingBoxProto.getWidth(),
+            /*bottom=*/ boundingBoxProto.getYmin() + boundingBoxProto.getHeight());
+      }
+      detections.add(
+          com.google.mediapipe.tasks.components.containers.Detection.create(
+              categories, boundingBox));
+    }
+    return new AutoValue_ObjectDetectionResult(
+        timestampMs, Collections.unmodifiableList(detections));
+  }
+}

mediapipe/tasks/java/com/google/mediapipe/tasks/vision/objectdetector/ObjectDetector.java

@@ -0,0 +1,418 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.vision.objectdetector;
+
+import android.content.Context;
+import android.os.ParcelFileDescriptor;
+import com.google.auto.value.AutoValue;
+import com.google.mediapipe.proto.CalculatorOptionsProto.CalculatorOptions;
+import com.google.mediapipe.framework.AndroidPacketGetter;
+import com.google.mediapipe.framework.Packet;
+import com.google.mediapipe.framework.PacketGetter;
+import com.google.mediapipe.framework.image.BitmapImageBuilder;
+import com.google.mediapipe.framework.image.Image;
+import com.google.mediapipe.tasks.core.BaseOptions;
+import com.google.mediapipe.tasks.core.ErrorListener;
+import com.google.mediapipe.tasks.core.OutputHandler;
+import com.google.mediapipe.tasks.core.OutputHandler.ResultListener;
+import com.google.mediapipe.tasks.core.TaskInfo;
+import com.google.mediapipe.tasks.core.TaskOptions;
+import com.google.mediapipe.tasks.core.TaskRunner;
+import com.google.mediapipe.tasks.core.proto.BaseOptionsProto;
+import com.google.mediapipe.tasks.vision.core.BaseVisionTaskApi;
+import com.google.mediapipe.tasks.vision.core.RunningMode;
+import com.google.mediapipe.formats.proto.DetectionProto.Detection;
+import java.io.File;
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * Performs object detection on images.
+ *
+ * <p>The API expects a TFLite model with <a
+ * href="https://www.tensorflow.org/lite/convert/metadata">TFLite Model Metadata.</a>.
+ *
+ * <p>The API supports models with one image input tensor and four output tensors. To be more
+ * specific, here are the requirements.
+ *
+ * <ul>
+ *   <li>Input image tensor ({@code kTfLiteUInt8}/{@code kTfLiteFloat32})
+ *       <ul>
+ *         <li>image input of size {@code [batch x height x width x channels]}.
+ *         <li>batch inference is not supported ({@code batch} is required to be 1).
+ *         <li>only RGB inputs are supported ({@code channels} is required to be 3).
+ *         <li>if type is {@code kTfLiteFloat32}, NormalizationOptions are required to be attached
+ *             to the metadata for input normalization.
+ *       </ul>
+ *   <li>Output tensors must be the 4 outputs of a {@code DetectionPostProcess} op, i.e:
+ *       <ul>
+ *         <li>Location tensor ({@code kTfLiteFloat32}):
+ *             <ul>
+ *               <li>tensor of size {@code [1 x num_results x 4]}, the inner array representing
+ *                   bounding boxes in the form [top, left, right, bottom].
+ *               <li>{@code BoundingBoxProperties} are required to be attached to the metadata and
+ *                   must specify {@code type=BOUNDARIES} and {@code coordinate_type=RATIO}.
+ *             </ul>
+ *         <li>Classes tensor ({@code kTfLiteFloat32}):
+ *             <ul>
+ *               <li>tensor of size {@code [1 x num_results]}, each value representing the integer
+ *                   index of a class.
+ *               <li>if label maps are attached to the metadata as {@code TENSOR_VALUE_LABELS}
+ *                   associated files, they are used to convert the tensor values into labels.
+ *             </ul>
+ *         <li>scores tensor ({@code kTfLiteFloat32}):
+ *             <ul>
+ *               <li>tensor of size {@code [1 x num_results]}, each value representing the score of
+ *                   the detected object.
+ *             </ul>
+ *         <li>Number of detection tensor ({@code kTfLiteFloat32}):
+ *             <ul>
+ *               <li>integer num_results as a tensor of size {@code [1]}.
+ *             </ul>
+ *       </ul>
+ * </ul>
+ *
+ * <p>An example of such model can be found on <a
+ * href="https://tfhub.dev/google/lite-model/object_detection/mobile_object_localizer_v1/1/metadata/1">TensorFlow
+ * Hub.</a>.
+ */
+public final class ObjectDetector extends BaseVisionTaskApi {
+  private static final String TAG = ObjectDetector.class.getSimpleName();
+  private static final String IMAGE_IN_STREAM_NAME = "image_in";
+  private static final List<String> INPUT_STREAMS =
+      Collections.unmodifiableList(Arrays.asList("IMAGE:" + IMAGE_IN_STREAM_NAME));
+  private static final List<String> OUTPUT_STREAMS =
+      Collections.unmodifiableList(Arrays.asList("DETECTIONS:detections_out", "IMAGE:image_out"));
+  private static final int DETECTIONS_OUT_STREAM_INDEX = 0;
+  private static final int IMAGE_OUT_STREAM_INDEX = 1;
+  private static final String TASK_GRAPH_NAME = "mediapipe.tasks.vision.ObjectDetectorGraph";
+
+  /**
+   * Creates an {@link ObjectDetector} instance from a model file and the default {@link
+   * ObjectDetectorOptions}.
+   *
+   * @param context an Android {@link Context}.
+   * @param modelPath path to the detection model with metadata in the assets.
+   * @throws MediaPipeException if there is an error during {@link ObjectDetector} creation.
+   */
+  public static ObjectDetector createFromFile(Context context, String modelPath) {
+    BaseOptions baseOptions = BaseOptions.builder().setModelAssetPath(modelPath).build();
+    return createFromOptions(
+        context, ObjectDetectorOptions.builder().setBaseOptions(baseOptions).build());
+  }
+
+  /**
+   * Creates an {@link ObjectDetector} instance from a model file and the default {@link
+   * ObjectDetectorOptions}.
+   *
+   * @param context an Android {@link Context}.
+   * @param modelFile the detection model {@link File} instance.
+   * @throws IOException if an I/O error occurs when opening the tflite model file.
+   * @throws MediaPipeException if there is an error during {@link ObjectDetector} creation.
+   */
+  public static ObjectDetector createFromFile(Context context, File modelFile) throws IOException {
+    try (ParcelFileDescriptor descriptor =
+        ParcelFileDescriptor.open(modelFile, ParcelFileDescriptor.MODE_READ_ONLY)) {
+      BaseOptions baseOptions =
+          BaseOptions.builder().setModelAssetFileDescriptor(descriptor.getFd()).build();
+      return createFromOptions(
+          context, ObjectDetectorOptions.builder().setBaseOptions(baseOptions).build());
+    }
+  }
+
+  /**
+   * Creates an {@link ObjectDetector} instance from a model buffer and the default {@link
+   * ObjectDetectorOptions}.
+   *
+   * @param context an Android {@link Context}.
+   * @param modelBuffer a direct {@link ByteBuffer} or a {@link MappedByteBuffer} of the detection
+   *     model.
+   * @throws MediaPipeException if there is an error during {@link ObjectDetector} creation.
+   */
+  public static ObjectDetector createFromBuffer(Context context, final ByteBuffer modelBuffer) {
+    BaseOptions baseOptions = BaseOptions.builder().setModelAssetBuffer(modelBuffer).build();
+    return createFromOptions(
+        context, ObjectDetectorOptions.builder().setBaseOptions(baseOptions).build());
+  }
+
+  /**
+   * Creates an {@link ObjectDetector} instance from an {@link ObjectDetectorOptions}.
+   *
+   * @param context an Android {@link Context}.
+   * @param detectorOptions a {@link ObjectDetectorOptions} instance.
+   * @throws MediaPipeException if there is an error during {@link ObjectDetector} creation.
+   */
+  public static ObjectDetector createFromOptions(
+      Context context, ObjectDetectorOptions detectorOptions) {
+    // TODO: Consolidate OutputHandler and TaskRunner.
+    OutputHandler<ObjectDetectionResult, Image> handler = new OutputHandler<>();
+    handler.setOutputPacketConverter(
+        new OutputHandler.OutputPacketConverter<ObjectDetectionResult, Image>() {
+          @Override
+          public ObjectDetectionResult convertToTaskResult(List<Packet> packets) {
+            return ObjectDetectionResult.create(
+                PacketGetter.getProtoVector(
+                    packets.get(DETECTIONS_OUT_STREAM_INDEX), Detection.parser()),
+                packets.get(DETECTIONS_OUT_STREAM_INDEX).getTimestamp());
+          }
+
+          @Override
+          public Image convertToTaskInput(List<Packet> packets) {
+            return new BitmapImageBuilder(
+                    AndroidPacketGetter.getBitmapFromRgb(packets.get(IMAGE_OUT_STREAM_INDEX)))
+                .build();
+          }
+        });
+    detectorOptions.resultListener().ifPresent(handler::setResultListener);
+    detectorOptions.errorListener().ifPresent(handler::setErrorListener);
+    TaskRunner runner =
+        TaskRunner.create(
+            context,
+            TaskInfo.<ObjectDetectorOptions>builder()
+                .setTaskGraphName(TASK_GRAPH_NAME)
+                .setInputStreams(INPUT_STREAMS)
+                .setOutputStreams(OUTPUT_STREAMS)
+                .setTaskOptions(detectorOptions)
+                .setEnableFlowLimiting(detectorOptions.runningMode() == RunningMode.LIVE_STREAM)
+                .build(),
+            handler);
+    detectorOptions.errorListener().ifPresent(runner::setErrorListener);
+    return new ObjectDetector(runner, detectorOptions.runningMode());
+  }
+
+  /**
+   * Constructor to initialize an {@link ObjectDetector} from a {@link TaskRunner} and a {@link
+   * RunningMode}.
+   *
+   * @param taskRunner a {@link TaskRunner}.
+   * @param runningMode a mediapipe vision task {@link RunningMode}.
+   */
+  private ObjectDetector(TaskRunner taskRunner, RunningMode runningMode) {
+    super(taskRunner, runningMode);
+  }
+
+  /**
+   * Performs object detection on the provided single image. Only use this method when the {@link
+   * ObjectDetector} is created with {@link RunningMode.IMAGE}.
+   *
+   * <p>{@link ObjectDetector} supports the following color space types:
+   *
+   * <ul>
+   *   <li>{@link Bitmap.Config.ARGB_8888}
+   * </ul>
+   *
+   * @param inputImage a MediaPipe {@link Image} object for processing.
+   * @throws MediaPipeException if there is an internal error.
+   */
+  public ObjectDetectionResult detect(Image inputImage) {
+    return (ObjectDetectionResult) processImageData(IMAGE_IN_STREAM_NAME, inputImage);
+  }
+
+  /**
+   * Performs object detection on the provided video frame. Only use this method when the {@link
+   * ObjectDetector} is created with {@link RunningMode.VIDEO}.
+   *
+   * <p>It's required to provide the video frame's timestamp (in milliseconds). The input timestamps
+   * must be monotonically increasing.
+   *
+   * <p>{@link ObjectDetector} supports the following color space types:
+   *
+   * <ul>
+   *   <li>{@link Bitmap.Config.ARGB_8888}
+   * </ul>
+   *
+   * @param inputImage a MediaPipe {@link Image} object for processing.
+   * @param inputTimestampMs the input timestamp (in milliseconds).
+   * @throws MediaPipeException if there is an internal error.
+   */
+  public ObjectDetectionResult detectForVideo(Image inputImage, long inputTimestampMs) {
+    return (ObjectDetectionResult)
+        processVideoData(IMAGE_IN_STREAM_NAME, inputImage, inputTimestampMs);
+  }
+
+  /**
+   * Sends live image data to perform object detection, and the results will be available via the
+   * {@link ResultListener} provided in the {@link ObjectDetectorOptions}. Only use this method when
+   * the {@link ObjectDetector} is created with {@link RunningMode.LIVE_STREAM}.
+   *
+   * <p>It's required to provide a timestamp (in milliseconds) to indicate when the input image is
+   * sent to the object detector. The input timestamps must be monotonically increasing.
+   *
+   * <p>{@link ObjectDetector} supports the following color space types:
+   *
+   * <ul>
+   *   <li>{@link Bitmap.Config.ARGB_8888}
+   * </ul>
+   *
+   * @param inputImage a MediaPipe {@link Image} object for processing.
+   * @param inputTimestampMs the input timestamp (in milliseconds).
+   * @throws MediaPipeException if there is an internal error.
+   */
+  public void detectAsync(Image inputImage, long inputTimestampMs) {
+    sendLiveStreamData(IMAGE_IN_STREAM_NAME, inputImage, inputTimestampMs);
+  }
+
+  /** Options for setting up an {@link ObjectDetector}. */
+  @AutoValue
+  public abstract static class ObjectDetectorOptions extends TaskOptions {
+
+    /** Builder for {@link ObjectDetectorOptions}. */
+    @AutoValue.Builder
+    public abstract static class Builder {
+      /** Sets the base options for the object detector task. */
+      public abstract Builder setBaseOptions(BaseOptions value);
+
+      /**
+       * Sets the running mode for the object detector task. Default to the image mode. Object
+       * detector has three modes:
+       *
+       * <ul>
+       *   <li>IMAGE: The mode for detecting objects on single image inputs.
+       *   <li>VIDEO: The mode for detecting objects on the decoded frames of a video.
+       *   <li>LIVE_STREAM: The mode for for detecting objects on a live stream of input data, such
+       *       as from camera. In this mode, {@code setResultListener} must be called to set up a
+       *       listener to receive the detection results asynchronously.
+       * </ul>
+       */
+      public abstract Builder setRunningMode(RunningMode value);
+
+      /**
+       * Sets the locale to use for display names specified through the TFLite Model Metadata, if
+       * any. Defaults to English.
+       */
+      public abstract Builder setDisplayNamesLocale(String value);
+
+      /**
+       * Sets the optional maximum number of top-scored detection results to return.
+       *
+       * <p>Overrides the ones provided in the model metadata. Results below this value are
+       * rejected.
+       */
+      public abstract Builder setMaxResults(Integer value);
+
+      /**
+       * Sets the optional score threshold that overrides the one provided in the model metadata (if
+       * any). Results below this value are rejected.
+       */
+      public abstract Builder setScoreThreshold(Float value);
+
+      /**
+       * Sets the optional allowlist of category names.
+       *
+       * <p>If non-empty, detection results whose category name is not in this set will be filtered
+       * out. Duplicate or unknown category names are ignored. Mutually exclusive with {@code
+       * categoryDenylist}.
+       */
+      public abstract Builder setCategoryAllowlist(List<String> value);
+
+      /**
+       * Sets the optional denylist of category names.
+       *
+       * <p>If non-empty, detection results whose category name is in this set will be filtered out.
+       * Duplicate or unknown category names are ignored. Mutually exclusive with {@code
+       * categoryAllowlist}.
+       */
+      public abstract Builder setCategoryDenylist(List<String> value);
+
+      /**
+       * Sets the result listener to receive the detection results asynchronously when the object
+       * detector is in the live stream mode.
+       */
+      public abstract Builder setResultListener(ResultListener<ObjectDetectionResult, Image> value);
+
+      /** Sets an optional error listener. */
+      public abstract Builder setErrorListener(ErrorListener value);
+
+      abstract ObjectDetectorOptions autoBuild();
+
+      /**
+       * Validates and builds the {@link ObjectDetectorOptions} instance.
+       *
+       * @throws IllegalArgumentException if the result listener and the running mode are not
+       *     properly configured. The result listener should only be set when the object detector is
+       *     in the live stream mode.
+       */
+      public final ObjectDetectorOptions build() {
+        ObjectDetectorOptions options = autoBuild();
+        if (options.runningMode() == RunningMode.LIVE_STREAM) {
+          if (!options.resultListener().isPresent()) {
+            throw new IllegalArgumentException(
+                "The object detector is in the live stream mode, a user-defined result listener"
+                    + " must be provided in ObjectDetectorOptions.");
+          }
+        } else if (options.resultListener().isPresent()) {
+          throw new IllegalArgumentException(
+              "The object detector is in the image or the video mode, a user-defined result"
+                  + " listener shouldn't be provided in ObjectDetectorOptions.");
+        }
+        return options;
+      }
+    }
+
+    abstract BaseOptions baseOptions();
+
+    abstract RunningMode runningMode();
+
+    abstract Optional<String> displayNamesLocale();
+
+    abstract Optional<Integer> maxResults();
+
+    abstract Optional<Float> scoreThreshold();
+
+    abstract List<String> categoryAllowlist();
+
+    abstract List<String> categoryDenylist();
+
+    abstract Optional<ResultListener<ObjectDetectionResult, Image>> resultListener();
+
+    abstract Optional<ErrorListener> errorListener();
+
+    public static Builder builder() {
+      return new AutoValue_ObjectDetector_ObjectDetectorOptions.Builder()
+          .setRunningMode(RunningMode.IMAGE)
+          .setCategoryAllowlist(Collections.emptyList())
+          .setCategoryDenylist(Collections.emptyList());
+    }
+
+    /** Converts a {@link ObjectDetectorOptions} to a {@link CalculatorOptions} protobuf message. */
+    @Override
+    public CalculatorOptions convertToCalculatorOptionsProto() {
+      BaseOptionsProto.BaseOptions.Builder baseOptionsBuilder =
+          BaseOptionsProto.BaseOptions.newBuilder();
+      baseOptionsBuilder.setUseStreamMode(runningMode() != RunningMode.IMAGE);
+      baseOptionsBuilder.mergeFrom(convertBaseOptionsToProto(baseOptions()));
+      ObjectDetectorOptionsProto.ObjectDetectorOptions.Builder taskOptionsBuilder =
+          ObjectDetectorOptionsProto.ObjectDetectorOptions.newBuilder()
+              .setBaseOptions(baseOptionsBuilder);
+      displayNamesLocale().ifPresent(taskOptionsBuilder::setDisplayNamesLocale);
+      maxResults().ifPresent(taskOptionsBuilder::setMaxResults);
+      scoreThreshold().ifPresent(taskOptionsBuilder::setScoreThreshold);
+      if (!categoryAllowlist().isEmpty()) {
+        taskOptionsBuilder.addAllCategoryAllowlist(categoryAllowlist());
+      }
+      if (!categoryDenylist().isEmpty()) {
+        taskOptionsBuilder.addAllCategoryDenylist(categoryDenylist());
+      }
+      return CalculatorOptions.newBuilder()
+          .setExtension(
+              ObjectDetectorOptionsProto.ObjectDetectorOptions.ext, taskOptionsBuilder.build())
+          .build();
+    }
+  }
+}

mediapipe/tasks/javatests/com/google/mediapipe/tasks/core/BUILD

@@ -11,3 +11,15 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+
+package(default_visibility = ["//mediapipe/tasks:internal"])
+
+licenses(["notice"])
+
+android_library(
+    name = "test_utils",
+    srcs = ["TestUtils.java"],
+    deps = [
+        "//third_party/java/android_libs/guava_jdk5:io",
+    ],
+)

mediapipe/tasks/javatests/com/google/mediapipe/tasks/core/TestUtils.java

@@ -0,0 +1,83 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.core;
+
+import android.content.Context;
+import android.content.res.AssetManager;
+import com.google.common.io.ByteStreams;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+/** Helper class for the Java test in MediaPipe Tasks. */
+public final class TestUtils {
+
+  /**
+   * Loads the file and create a {@link File} object by reading a file from the asset directory.
+   * Simulates downloading or reading a file that's not precompiled with the app.
+   *
+   * @return a {@link File} object for the model.
+   */
+  public static File loadFile(Context context, String fileName) {
+    File target = new File(context.getFilesDir(), fileName);
+    try (InputStream is = context.getAssets().open(fileName);
+        FileOutputStream os = new FileOutputStream(target)) {
+      ByteStreams.copy(is, os);
+    } catch (IOException e) {
+      throw new AssertionError("Failed to load model file at " + fileName, e);
+    }
+    return target;
+  }
+
+  /**
+   * Reads a file into a direct {@link ByteBuffer} object from the asset directory.
+   *
+   * @return a {@link ByteBuffer} object for the file.
+   */
+  public static ByteBuffer loadToDirectByteBuffer(Context context, String fileName)
+      throws IOException {
+    AssetManager assetManager = context.getAssets();
+    InputStream inputStream = assetManager.open(fileName);
+    byte[] bytes = ByteStreams.toByteArray(inputStream);
+
+    ByteBuffer buffer = ByteBuffer.allocateDirect(bytes.length).order(ByteOrder.nativeOrder());
+    buffer.put(bytes);
+    return buffer;
+  }
+
+  /**
+   * Reads a file into a non-direct {@link ByteBuffer} object from the asset directory.
+   *
+   * @return a {@link ByteBuffer} object for the file.
+   */
+  public static ByteBuffer loadToNonDirectByteBuffer(Context context, String fileName)
+      throws IOException {
+    AssetManager assetManager = context.getAssets();
+    InputStream inputStream = assetManager.open(fileName);
+    byte[] bytes = ByteStreams.toByteArray(inputStream);
+    return ByteBuffer.wrap(bytes);
+  }
+
+  public enum ByteBufferType {
+    DIRECT,
+    BACK_UP_ARRAY,
+    OTHER // Non-direct ByteBuffer without a back-up array.
+  }
+
+  private TestUtils() {}
+}

mediapipe/tasks/javatests/com/google/mediapipe/tasks/vision/objectdetector/BUILD

@@ -12,4 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+package(default_visibility = ["//mediapipe/tasks:internal"])
+
+licenses(["notice"])
+
 # TODO: Enable this in OSS

mediapipe/tasks/javatests/com/google/mediapipe/tasks/vision/objectdetector/ObjectDetectorTest.java

@@ -0,0 +1,456 @@
+// Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.mediapipe.tasks.vision.objectdetector;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertThrows;
+
+import android.content.res.AssetManager;
+import android.graphics.BitmapFactory;
+import android.graphics.RectF;
+import androidx.test.core.app.ApplicationProvider;
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+import com.google.mediapipe.framework.MediaPipeException;
+import com.google.mediapipe.framework.image.BitmapImageBuilder;
+import com.google.mediapipe.framework.image.Image;
+import com.google.mediapipe.tasks.components.containers.Category;
+import com.google.mediapipe.tasks.components.containers.Detection;
+import com.google.mediapipe.tasks.core.BaseOptions;
+import com.google.mediapipe.tasks.core.TestUtils;
+import com.google.mediapipe.tasks.vision.core.RunningMode;
+import com.google.mediapipe.tasks.vision.objectdetector.ObjectDetector.ObjectDetectorOptions;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.util.Arrays;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Suite;
+import org.junit.runners.Suite.SuiteClasses;
+
+/** Test for {@link ObjectDetector}. */
+@RunWith(Suite.class)
+@SuiteClasses({ObjectDetectorTest.General.class, ObjectDetectorTest.RunningModeTest.class})
+public class ObjectDetectorTest {
+  private static final String MODEL_FILE = "coco_ssd_mobilenet_v1_1.0_quant_2018_06_29.tflite";
+  private static final String CAT_AND_DOG_IMAGE = "cats_and_dogs.jpg";
+  private static final int IMAGE_WIDTH = 1200;
+  private static final int IMAGE_HEIGHT = 600;
+  private static final float CAT_SCORE = 0.69f;
+  private static final RectF catBoundingBox = new RectF(611, 164, 986, 596);
+  // TODO: Figure out why android_x86 and android_arm tests have slightly different
+  // scores (0.6875 vs 0.69921875).
+  private static final float SCORE_DIFF_TOLERANCE = 0.01f;
+  private static final float PIXEL_DIFF_TOLERANCE = 5.0f;
+
+  @RunWith(AndroidJUnit4.class)
+  public static final class General extends ObjectDetectorTest {
+
+    @Test
+    public void detect_successWithValidModels() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setMaxResults(1)
+              .build();
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options);
+      ObjectDetectionResult results = objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE));
+      assertContainsOnlyCat(results, catBoundingBox, CAT_SCORE);
+    }
+
+    @Test
+    public void detect_successWithNoOptions() throws Exception {
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromFile(ApplicationProvider.getApplicationContext(), MODEL_FILE);
+      ObjectDetectionResult results = objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE));
+      // Check if the object with the highest score is cat.
+      assertIsCat(results.detections().get(0).categories().get(0), CAT_SCORE);
+    }
+
+    @Test
+    public void detect_succeedsWithMaxResultsOption() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setMaxResults(8)
+              .build();
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options);
+      ObjectDetectionResult results = objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE));
+      // results should have 8 detected objects because maxResults was set to 8.
+      assertThat(results.detections()).hasSize(8);
+    }
+
+    @Test
+    public void detect_succeedsWithScoreThresholdOption() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setScoreThreshold(0.68f)
+              .build();
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options);
+      ObjectDetectionResult results = objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE));
+      // The score threshold should block all other other objects, except cat.
+      assertContainsOnlyCat(results, catBoundingBox, CAT_SCORE);
+    }
+
+    @Test
+    public void detect_succeedsWithAllowListOption() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setCategoryAllowlist(Arrays.asList("cat"))
+              .build();
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options);
+      ObjectDetectionResult results = objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE));
+      // Because of the allowlist, results should only contain cat, and there are 6 detected
+      // bounding boxes of cats in CAT_AND_DOG_IMAGE.
+      assertThat(results.detections()).hasSize(5);
+    }
+
+    @Test
+    public void detect_succeedsWithDenyListOption() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setCategoryDenylist(Arrays.asList("cat"))
+              .build();
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options);
+      ObjectDetectionResult results = objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE));
+      // Because of the denylist, the highest result is not cat anymore.
+      assertThat(results.detections().get(0).categories().get(0).categoryName())
+          .isNotEqualTo("cat");
+    }
+
+    @Test
+    public void detect_succeedsWithModelFileObject() throws Exception {
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromFile(
+              ApplicationProvider.getApplicationContext(),
+              TestUtils.loadFile(ApplicationProvider.getApplicationContext(), MODEL_FILE));
+      ObjectDetectionResult results = objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE));
+      // Check if the object with the highest score is cat.
+      assertIsCat(results.detections().get(0).categories().get(0), CAT_SCORE);
+    }
+
+    @Test
+    public void detect_succeedsWithModelBuffer() throws Exception {
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromBuffer(
+              ApplicationProvider.getApplicationContext(),
+              TestUtils.loadToDirectByteBuffer(
+                  ApplicationProvider.getApplicationContext(), MODEL_FILE));
+      ObjectDetectionResult results = objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE));
+      // Check if the object with the highest score is cat.
+      assertIsCat(results.detections().get(0).categories().get(0), CAT_SCORE);
+    }
+
+    @Test
+    public void detect_succeedsWithModelBufferAndOptions() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(
+                  BaseOptions.builder()
+                      .setModelAssetBuffer(
+                          TestUtils.loadToDirectByteBuffer(
+                              ApplicationProvider.getApplicationContext(), MODEL_FILE))
+                      .build())
+              .setMaxResults(1)
+              .build();
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options);
+      ObjectDetectionResult results = objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE));
+      assertContainsOnlyCat(results, catBoundingBox, CAT_SCORE);
+    }
+
+    @Test
+    public void create_failsWithMissingModel() throws Exception {
+      String nonexistentFile = "/path/to/non/existent/file";
+      MediaPipeException exception =
+          assertThrows(
+              MediaPipeException.class,
+              () ->
+                  ObjectDetector.createFromFile(
+                      ApplicationProvider.getApplicationContext(), nonexistentFile));
+      assertThat(exception).hasMessageThat().contains(nonexistentFile);
+    }
+
+    @Test
+    public void create_failsWithInvalidModelBuffer() throws Exception {
+      // Create a non-direct model ByteBuffer.
+      ByteBuffer modelBuffer =
+          TestUtils.loadToNonDirectByteBuffer(
+              ApplicationProvider.getApplicationContext(), MODEL_FILE);
+
+      IllegalArgumentException exception =
+          assertThrows(
+              IllegalArgumentException.class,
+              () ->
+                  ObjectDetector.createFromBuffer(
+                      ApplicationProvider.getApplicationContext(), modelBuffer));
+
+      assertThat(exception)
+          .hasMessageThat()
+          .contains("The model buffer should be either a direct ByteBuffer or a MappedByteBuffer.");
+    }
+
+    @Test
+    public void detect_failsWithBothAllowAndDenyListOption() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setCategoryAllowlist(Arrays.asList("cat"))
+              .setCategoryDenylist(Arrays.asList("dog"))
+              .build();
+      MediaPipeException exception =
+          assertThrows(
+              MediaPipeException.class,
+              () ->
+                  ObjectDetector.createFromOptions(
+                      ApplicationProvider.getApplicationContext(), options));
+      assertThat(exception)
+          .hasMessageThat()
+          .contains("`category_allowlist` and `category_denylist` are mutually exclusive options.");
+    }
+
+    // TODO: Implement detect_succeedsWithFloatImages, detect_succeedsWithOrientation,
+    // detect_succeedsWithNumThreads, detect_successWithNumThreadsFromBaseOptions,
+    // detect_failsWithInvalidNegativeNumThreads, detect_failsWithInvalidNumThreadsAsZero.
+  }
+
+  @RunWith(AndroidJUnit4.class)
+  public static final class RunningModeTest extends ObjectDetectorTest {
+
+    @Test
+    public void create_failsWithIllegalResultListenerInNonLiveStreamMode() throws Exception {
+      for (RunningMode mode : new RunningMode[] {RunningMode.IMAGE, RunningMode.VIDEO}) {
+        IllegalArgumentException exception =
+            assertThrows(
+                IllegalArgumentException.class,
+                () ->
+                    ObjectDetectorOptions.builder()
+                        .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+                        .setRunningMode(mode)
+                        .setResultListener((objectDetectionResult, inputImage) -> {})
+                        .build());
+        assertThat(exception)
+            .hasMessageThat()
+            .contains("a user-defined result listener shouldn't be provided");
+      }
+    }
+
+    @Test
+    public void create_failsWithMissingResultListenerInLiveSteamMode() throws Exception {
+      IllegalArgumentException exception =
+          assertThrows(
+              IllegalArgumentException.class,
+              () ->
+                  ObjectDetectorOptions.builder()
+                      .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+                      .setRunningMode(RunningMode.LIVE_STREAM)
+                      .build());
+      assertThat(exception)
+          .hasMessageThat()
+          .contains("a user-defined result listener must be provided");
+    }
+
+    @Test
+    public void detect_failsWithCallingWrongApiInImageMode() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setRunningMode(RunningMode.IMAGE)
+              .build();
+
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options);
+      MediaPipeException exception =
+          assertThrows(
+              MediaPipeException.class,
+              () -> objectDetector.detectForVideo(getImageFromAsset(CAT_AND_DOG_IMAGE), 0));
+      assertThat(exception).hasMessageThat().contains("not initialized with the video mode");
+      exception =
+          assertThrows(
+              MediaPipeException.class,
+              () -> objectDetector.detectAsync(getImageFromAsset(CAT_AND_DOG_IMAGE), 0));
+      assertThat(exception).hasMessageThat().contains("not initialized with the live stream mode");
+    }
+
+    @Test
+    public void detect_failsWithCallingWrongApiInVideoMode() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setRunningMode(RunningMode.VIDEO)
+              .build();
+
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options);
+      MediaPipeException exception =
+          assertThrows(
+              MediaPipeException.class,
+              () -> objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE)));
+      assertThat(exception).hasMessageThat().contains("not initialized with the image mode");
+      exception =
+          assertThrows(
+              MediaPipeException.class,
+              () -> objectDetector.detectAsync(getImageFromAsset(CAT_AND_DOG_IMAGE), 0));
+      assertThat(exception).hasMessageThat().contains("not initialized with the live stream mode");
+    }
+
+    @Test
+    public void detect_failsWithCallingWrongApiInLiveSteamMode() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setRunningMode(RunningMode.LIVE_STREAM)
+              .setResultListener((objectDetectionResult, inputImage) -> {})
+              .build();
+
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options);
+
+      MediaPipeException exception =
+          assertThrows(
+              MediaPipeException.class,
+              () -> objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE)));
+      assertThat(exception).hasMessageThat().contains("not initialized with the image mode");
+      exception =
+          assertThrows(
+              MediaPipeException.class,
+              () -> objectDetector.detectForVideo(getImageFromAsset(CAT_AND_DOG_IMAGE), 0));
+      assertThat(exception).hasMessageThat().contains("not initialized with the video mode");
+    }
+
+    @Test
+    public void detect_successWithImageMode() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setRunningMode(RunningMode.IMAGE)
+              .setMaxResults(1)
+              .build();
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options);
+      ObjectDetectionResult results = objectDetector.detect(getImageFromAsset(CAT_AND_DOG_IMAGE));
+      assertContainsOnlyCat(results, catBoundingBox, CAT_SCORE);
+    }
+
+    @Test
+    public void detect_successWithVideoMode() throws Exception {
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setRunningMode(RunningMode.VIDEO)
+              .setMaxResults(1)
+              .build();
+      ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options);
+      for (int i = 0; i < 3; i++) {
+        ObjectDetectionResult results =
+            objectDetector.detectForVideo(getImageFromAsset(CAT_AND_DOG_IMAGE), i);
+        assertContainsOnlyCat(results, catBoundingBox, CAT_SCORE);
+      }
+    }
+
+    @Test
+    public void detect_failsWithOutOfOrderInputTimestamps() throws Exception {
+      Image image = getImageFromAsset(CAT_AND_DOG_IMAGE);
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setRunningMode(RunningMode.LIVE_STREAM)
+              .setResultListener(
+                  (objectDetectionResult, inputImage) -> {
+                    assertContainsOnlyCat(objectDetectionResult, catBoundingBox, CAT_SCORE);
+                    assertImageSizeIsExpected(inputImage);
+                  })
+              .setMaxResults(1)
+              .build();
+      try (ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options)) {
+        objectDetector.detectAsync(image, 1);
+        MediaPipeException exception =
+            assertThrows(MediaPipeException.class, () -> objectDetector.detectAsync(image, 0));
+        assertThat(exception)
+            .hasMessageThat()
+            .contains("having a smaller timestamp than the processed timestamp");
+      }
+    }
+
+    @Test
+    public void detect_successWithLiveSteamMode() throws Exception {
+      Image image = getImageFromAsset(CAT_AND_DOG_IMAGE);
+      ObjectDetectorOptions options =
+          ObjectDetectorOptions.builder()
+              .setBaseOptions(BaseOptions.builder().setModelAssetPath(MODEL_FILE).build())
+              .setRunningMode(RunningMode.LIVE_STREAM)
+              .setResultListener(
+                  (objectDetectionResult, inputImage) -> {
+                    assertContainsOnlyCat(objectDetectionResult, catBoundingBox, CAT_SCORE);
+                    assertImageSizeIsExpected(inputImage);
+                  })
+              .setMaxResults(1)
+              .build();
+      try (ObjectDetector objectDetector =
+          ObjectDetector.createFromOptions(ApplicationProvider.getApplicationContext(), options)) {
+        for (int i = 0; i < 3; i++) {
+          objectDetector.detectAsync(image, i);
+        }
+      }
+    }
+  }
+
+  private static Image getImageFromAsset(String filePath) throws Exception {
+    AssetManager assetManager = ApplicationProvider.getApplicationContext().getAssets();
+    InputStream istr = assetManager.open(filePath);
+    return new BitmapImageBuilder(BitmapFactory.decodeStream(istr)).build();
+  }
+
+  // Checks if results has one and only detection result, which is a cat.
+  private static void assertContainsOnlyCat(
+      ObjectDetectionResult result, RectF expectedBoundingBox, float expectedScore) {
+    assertThat(result.detections()).hasSize(1);
+    Detection catResult = result.detections().get(0);
+    assertApproximatelyEqualBoundingBoxes(catResult.boundingBox(), expectedBoundingBox);
+    // We only support one category for each detected object at this point.
+    assertIsCat(catResult.categories().get(0), expectedScore);
+  }
+
+  private static void assertIsCat(Category category, float expectedScore) {
+    assertThat(category.categoryName()).isEqualTo("cat");
+    // coco_ssd_mobilenet_v1_1.0_quant_2018_06_29.tflite does not support label locale.
+    assertThat(category.displayName()).isEmpty();
+    assertThat((double) category.score()).isWithin(SCORE_DIFF_TOLERANCE).of(expectedScore);
+    assertThat(category.index()).isEqualTo(-1);
+  }
+
+  private static void assertApproximatelyEqualBoundingBoxes(
+      RectF boundingBox1, RectF boundingBox2) {
+    assertThat(boundingBox1.left).isWithin(PIXEL_DIFF_TOLERANCE).of(boundingBox2.left);
+    assertThat(boundingBox1.top).isWithin(PIXEL_DIFF_TOLERANCE).of(boundingBox2.top);
+    assertThat(boundingBox1.right).isWithin(PIXEL_DIFF_TOLERANCE).of(boundingBox2.right);
+    assertThat(boundingBox1.bottom).isWithin(PIXEL_DIFF_TOLERANCE).of(boundingBox2.bottom);
+  }
+
+  private static void assertImageSizeIsExpected(Image inputImage) {
+    assertThat(inputImage).isNotNull();
+    assertThat(inputImage.getWidth()).isEqualTo(IMAGE_WIDTH);
+    assertThat(inputImage.getHeight()).isEqualTo(IMAGE_HEIGHT);
+  }
+}

mediapipe/tasks/metadata/BUILD

@@ -1,4 +1,4 @@
-load("@flatbuffers//:build_defs.bzl", "flatbuffer_cc_library")
+load("@flatbuffers//:build_defs.bzl", "flatbuffer_cc_library", "flatbuffer_py_library")
 
 package(
     default_visibility = [
@@ -14,3 +14,13 @@ flatbuffer_cc_library(
     name = "metadata_schema_cc",
     srcs = ["metadata_schema.fbs"],
 )
+
+flatbuffer_py_library(
+    name = "schema_py",
+    srcs = ["@org_tensorflow//tensorflow/lite/schema:schema.fbs"],
+)
+
+flatbuffer_py_library(
+    name = "metadata_schema_py",
+    srcs = ["metadata_schema.fbs"],
+)

mediapipe/tasks/python/components/containers/BUILD

@@ -31,7 +31,7 @@ py_library(
     name = "category",
     srcs = ["category.py"],
     deps = [
-        "//mediapipe/tasks/cc/components/containers:category_py_pb2",
+        "//mediapipe/tasks/cc/components/containers/proto:category_py_pb2",
         "//mediapipe/tasks/python/core:optional_dependencies",
     ],
 )

mediapipe/tasks/python/components/containers/category.py

@@ -16,7 +16,7 @@
 import dataclasses
 from typing import Any
 
-from mediapipe.tasks.cc.components.containers import category_pb2
+from mediapipe.tasks.cc.components.containers.proto import category_pb2
 from mediapipe.tasks.python.core.optional_dependencies import doc_controls
 
 _CategoryProto = category_pb2.Category

mediapipe/tasks/python/core/pybind/BUILD

@@ -27,6 +27,7 @@ pybind_library(
         "//mediapipe/framework/api2:builder",
         "//mediapipe/framework/port:parse_text_proto",
         "//mediapipe/python/pybind:util",
+        "//mediapipe/tasks/cc/core:mediapipe_builtin_op_resolver",
         "//mediapipe/tasks/cc/core:task_runner",
         "@org_tensorflow//tensorflow/lite/core/api:op_resolver",
         "@pybind11_protobuf//pybind11_protobuf:native_proto_caster",

mediapipe/tasks/python/core/pybind/task_runner.cc

@@ -16,6 +16,7 @@
 
 #include "mediapipe/framework/calculator.pb.h"
 #include "mediapipe/python/pybind/util.h"
+#include "mediapipe/tasks/cc/core/mediapipe_builtin_op_resolver.h"
 #include "mediapipe/tasks/cc/core/task_runner.h"
 #include "pybind11/stl.h"
 #include "pybind11_protobuf/native_proto_caster.h"
@@ -75,7 +76,7 @@ mode) or not (synchronous mode).)doc");
         }
         auto task_runner = TaskRunner::Create(
             std::move(graph_config),
-            absl::make_unique<tflite::ops::builtin::BuiltinOpResolver>(),
+            absl::make_unique<core::MediaPipeBuiltinOpResolver>(),
             std::move(callback));
         RaisePyErrorIfNotOk(task_runner.status());
         return std::move(*task_runner);

mediapipe/tasks/python/metadata/BUILD

@@ -0,0 +1,38 @@
+load("//mediapipe/tasks/metadata:build_defs.bzl", "stamp_metadata_parser_version")
+
+package(
+    licenses = ["notice"],  # Apache 2.0
+)
+
+stamp_metadata_parser_version(
+    name = "metadata_parser_py",
+    srcs = ["metadata_parser.py.template"],
+    outs = ["metadata_parser.py"],
+)
+
+py_library(
+    name = "metadata",
+    srcs = [
+        "metadata.py",
+        ":metadata_parser_py",
+    ],
+    data = ["//mediapipe/tasks/metadata:metadata_schema.fbs"],
+    srcs_version = "PY3",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//mediapipe/tasks/cc/metadata/python:_pywrap_metadata_version",
+        "//mediapipe/tasks/metadata:metadata_schema_py",
+        "//mediapipe/tasks/metadata:schema_py",
+        "//mediapipe/tasks/python/metadata/flatbuffers_lib:_pywrap_flatbuffers",
+        "@flatbuffers//:runtime_py",
+    ],
+)
+
+py_binary(
+    name = "metadata_displayer_cli",
+    srcs = ["metadata_displayer_cli.py"],
+    visibility = [
+        "//visibility:public",
+    ],
+    deps = [":metadata"],
+)

mediapipe/tasks/python/metadata/__init__.py

@@ -0,0 +1,13 @@
+# Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.

mediapipe/tasks/python/metadata/flatbuffers_lib/BUILD

@@ -0,0 +1,20 @@
+load("@org_tensorflow//tensorflow:tensorflow.bzl", "pybind_extension")
+
+package(
+    default_visibility = ["//mediapipe/tasks:internal"],
+    licenses = ["notice"],  # Apache 2.0
+)
+
+pybind_extension(
+    name = "_pywrap_flatbuffers",
+    srcs = [
+        "flatbuffers_lib.cc",
+    ],
+    features = ["-use_header_modules"],
+    module_name = "_pywrap_flatbuffers",
+    deps = [
+        "@flatbuffers",
+        "@local_config_python//:python_headers",
+        "@pybind11",
+    ],
+)

mediapipe/tasks/python/metadata/flatbuffers_lib/flatbuffers_lib.cc

@@ -0,0 +1,59 @@
+/* Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+==============================================================================*/
+
+#include "flatbuffers/flatbuffers.h"
+#include "flatbuffers/idl.h"
+#include "pybind11/pybind11.h"
+#include "pybind11/pytypes.h"
+#include "pybind11/stl.h"
+
+namespace tflite {
+namespace support {
+
+PYBIND11_MODULE(_pywrap_flatbuffers, m) {
+  pybind11::class_<flatbuffers::IDLOptions>(m, "IDLOptions")
+      .def(pybind11::init<>())
+      .def_readwrite("strict_json", &flatbuffers::IDLOptions::strict_json);
+  pybind11::class_<flatbuffers::Parser>(m, "Parser")
+      .def(pybind11::init<const flatbuffers::IDLOptions&>())
+      .def("parse",
+           [](flatbuffers::Parser* self, const std::string& source) {
+             return self->Parse(source.c_str());
+           })
+      .def_readonly("builder", &flatbuffers::Parser::builder_)
+      .def_readonly("error", &flatbuffers::Parser::error_);
+  pybind11::class_<flatbuffers::FlatBufferBuilder>(m, "FlatBufferBuilder")
+      .def("clear", &flatbuffers::FlatBufferBuilder::Clear)
+      .def("push_flat_buffer", [](flatbuffers::FlatBufferBuilder* self,
+                                  const std::string& contents) {
+        self->PushFlatBuffer(reinterpret_cast<const uint8_t*>(contents.c_str()),
+                             contents.length());
+      });
+  m.def("generate_text_file", &flatbuffers::GenerateTextFile);
+  m.def(
+      "generate_text",
+      [](const flatbuffers::Parser& parser,
+         const std::string& buffer) -> std::string {
+        std::string text;
+        if (!flatbuffers::GenerateText(
+                parser, reinterpret_cast<const void*>(buffer.c_str()), &text)) {
+          return "";
+        }
+        return text;
+      });
+}
+
+}  // namespace support
+}  // namespace tflite

mediapipe/tasks/python/metadata/metadata.py

@@ -0,0 +1,865 @@
+# Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+"""TensorFlow Lite metadata tools."""
+
+import copy
+import inspect
+import io
+import os
+import shutil
+import sys
+import tempfile
+import warnings
+import zipfile
+
+import flatbuffers
+from mediapipe.tasks.cc.metadata.python import _pywrap_metadata_version
+from mediapipe.tasks.metadata import metadata_schema_py_generated as _metadata_fb
+from mediapipe.tasks.metadata import schema_py_generated as _schema_fb
+from mediapipe.tasks.python.metadata.flatbuffers_lib import _pywrap_flatbuffers
+
+try:
+  # If exists, optionally use TensorFlow to open and check files. Used to
+  # support more than local file systems.
+  # In pip requirements, we doesn't necessarily need tensorflow as a dep.
+  import tensorflow as tf
+  _open_file = tf.io.gfile.GFile
+  _exists_file = tf.io.gfile.exists
+except ImportError as e:
+  # If TensorFlow package doesn't exist, fall back to original open and exists.
+  _open_file = open
+  _exists_file = os.path.exists
+
+
+def _maybe_open_as_binary(filename, mode):
+  """Maybe open the binary file, and returns a file-like."""
+  if hasattr(filename, "read"):  # A file-like has read().
+    return filename
+  openmode = mode if "b" in mode else mode + "b"  # Add binary explicitly.
+  return _open_file(filename, openmode)
+
+
+def _open_as_zipfile(filename, mode="r"):
+  """Open file as a zipfile.
+
+  Args:
+    filename: str or file-like or path-like, to the zipfile.
+    mode: str, common file mode for zip.
+          (See: https://docs.python.org/3/library/zipfile.html)
+
+  Returns:
+    A ZipFile object.
+  """
+  file_like = _maybe_open_as_binary(filename, mode)
+  return zipfile.ZipFile(file_like, mode)
+
+
+def _is_zipfile(filename):
+  """Checks whether it is a zipfile."""
+  with _maybe_open_as_binary(filename, "r") as f:
+    return zipfile.is_zipfile(f)
+
+
+def get_path_to_datafile(path):
+  """Gets the path to the specified file in the data dependencies.
+
+  The path is relative to the file calling the function.
+
+  It's a simple replacement of
+  "tensorflow.python.platform.resource_loader.get_path_to_datafile".
+
+  Args:
+    path: a string resource path relative to the calling file.
+
+  Returns:
+    The path to the specified file present in the data attribute of py_test
+    or py_binary.
+  """
+  data_files_path = os.path.dirname(inspect.getfile(sys._getframe(1)))  # pylint: disable=protected-access
+  return os.path.join(data_files_path, path)
+
+
+_FLATC_TFLITE_METADATA_SCHEMA_FILE = get_path_to_datafile(
+    "../../metadata/metadata_schema.fbs")
+
+
+# TODO: add delete method for associated files.
+class MetadataPopulator(object):
+  """Packs metadata and associated files into TensorFlow Lite model file.
+
+  MetadataPopulator can be used to populate metadata and model associated files
+  into a model file or a model buffer (in bytearray). It can also help to
+  inspect list of files that have been packed into the model or are supposed to
+  be packed into the model.
+
+  The metadata file (or buffer) should be generated based on the metadata
+  schema:
+  third_party/tensorflow/lite/schema/metadata_schema.fbs
+
+  Example usage:
+  Populate matadata and label file into an image classifier model.
+
+  First, based on metadata_schema.fbs, generate the metadata for this image
+  classifer model using Flatbuffers API. Attach the label file onto the ouput
+  tensor (the tensor of probabilities) in the metadata.
+
+  Then, pack the metadata and label file into the model as follows.
+
+    ```python
+    # Populating a metadata file (or a metadta buffer) and associated files to
+    a model file:
+    populator = MetadataPopulator.with_model_file(model_file)
+    # For metadata buffer (bytearray read from the metadata file), use:
+    # populator.load_metadata_buffer(metadata_buf)
+    populator.load_metadata_file(metadata_file)
+    populator.load_associated_files([label.txt])
+    # For associated file buffer (bytearray read from the file), use:
+    # populator.load_associated_file_buffers({"label.txt": b"file content"})
+    populator.populate()
+
+    # Populating a metadata file (or a metadata buffer) and associated files to
+    a model buffer:
+    populator = MetadataPopulator.with_model_buffer(model_buf)
+    populator.load_metadata_file(metadata_file)
+    populator.load_associated_files([label.txt])
+    populator.populate()
+    # Writing the updated model buffer into a file.
+    updated_model_buf = populator.get_model_buffer()
+    with open("updated_model.tflite", "wb") as f:
+      f.write(updated_model_buf)
+
+    # Transferring metadata and associated files from another TFLite model:
+    populator = MetadataPopulator.with_model_buffer(model_buf)
+    populator_dst.load_metadata_and_associated_files(src_model_buf)
+    populator_dst.populate()
+    updated_model_buf = populator.get_model_buffer()
+    with open("updated_model.tflite", "wb") as f:
+      f.write(updated_model_buf)
+    ```
+
+  Note that existing metadata buffer (if applied) will be overridden by the new
+  metadata buffer.
+  """
+  # As Zip API is used to concatenate associated files after tflite model file,
+  # the populating operation is developed based on a model file. For in-memory
+  # model buffer, we create a tempfile to serve the populating operation.
+  # Creating the deleting such a tempfile is handled by the class,
+  # _MetadataPopulatorWithBuffer.
+
+  METADATA_FIELD_NAME = "TFLITE_METADATA"
+  TFLITE_FILE_IDENTIFIER = b"TFL3"
+  METADATA_FILE_IDENTIFIER = b"M001"
+
+  def __init__(self, model_file):
+    """Constructor for MetadataPopulator.
+
+    Args:
+      model_file: valid path to a TensorFlow Lite model file.
+
+    Raises:
+      IOError: File not found.
+      ValueError: the model does not have the expected flatbuffer identifer.
+    """
+    _assert_model_file_identifier(model_file)
+    self._model_file = model_file
+    self._metadata_buf = None
+    # _associated_files is a dict of file name and file buffer.
+    self._associated_files = {}
+
+  @classmethod
+  def with_model_file(cls, model_file):
+    """Creates a MetadataPopulator object that populates data to a model file.
+
+    Args:
+      model_file: valid path to a TensorFlow Lite model file.
+
+    Returns:
+      MetadataPopulator object.
+
+    Raises:
+      IOError: File not found.
+      ValueError: the model does not have the expected flatbuffer identifer.
+    """
+    return cls(model_file)
+
+  # TODO: investigate if type check can be applied to model_buf for
+  # FB.
+  @classmethod
+  def with_model_buffer(cls, model_buf):
+    """Creates a MetadataPopulator object that populates data to a model buffer.
+
+    Args:
+      model_buf: TensorFlow Lite model buffer in bytearray.
+
+    Returns:
+      A MetadataPopulator(_MetadataPopulatorWithBuffer) object.
+
+    Raises:
+      ValueError: the model does not have the expected flatbuffer identifer.
+    """
+    return _MetadataPopulatorWithBuffer(model_buf)
+
+  def get_model_buffer(self):
+    """Gets the buffer of the model with packed metadata and associated files.
+
+    Returns:
+      Model buffer (in bytearray).
+    """
+    with _open_file(self._model_file, "rb") as f:
+      return f.read()
+
+  def get_packed_associated_file_list(self):
+    """Gets a list of associated files packed to the model file.
+
+    Returns:
+      List of packed associated files.
+    """
+    if not _is_zipfile(self._model_file):
+      return []
+
+    with _open_as_zipfile(self._model_file, "r") as zf:
+      return zf.namelist()
+
+  def get_recorded_associated_file_list(self):
+    """Gets a list of associated files recorded in metadata of the model file.
+
+    Associated files may be attached to a model, a subgraph, or an input/output
+    tensor.
+
+    Returns:
+      List of recorded associated files.
+    """
+    if not self._metadata_buf:
+      return []
+
+    metadata = _metadata_fb.ModelMetadataT.InitFromObj(
+        _metadata_fb.ModelMetadata.GetRootAsModelMetadata(
+            self._metadata_buf, 0))
+
+    return [
+        file.name.decode("utf-8")
+        for file in self._get_recorded_associated_file_object_list(metadata)
+    ]
+
+  def load_associated_file_buffers(self, associated_files):
+    """Loads the associated file buffers (in bytearray) to be populated.
+
+    Args:
+      associated_files: a dictionary of associated file names and corresponding
+        file buffers, such as {"file.txt": b"file content"}. If pass in file
+          paths for the file name, only the basename will be populated.
+    """
+
+    self._associated_files.update({
+        os.path.basename(name): buffers
+        for name, buffers in associated_files.items()
+    })
+
+  def load_associated_files(self, associated_files):
+    """Loads associated files that to be concatenated after the model file.
+
+    Args:
+      associated_files: list of file paths.
+
+    Raises:
+      IOError:
+        File not found.
+    """
+    for af_name in associated_files:
+      _assert_file_exist(af_name)
+      with _open_file(af_name, "rb") as af:
+        self.load_associated_file_buffers({af_name: af.read()})
+
+  def load_metadata_buffer(self, metadata_buf):
+    """Loads the metadata buffer (in bytearray) to be populated.
+
+    Args:
+      metadata_buf: metadata buffer (in bytearray) to be populated.
+
+    Raises:
+      ValueError: The metadata to be populated is empty.
+      ValueError: The metadata does not have the expected flatbuffer identifer.
+      ValueError: Cannot get minimum metadata parser version.
+      ValueError: The number of SubgraphMetadata is not 1.
+      ValueError: The number of input/output tensors does not match the number
+        of input/output tensor metadata.
+    """
+    if not metadata_buf:
+      raise ValueError("The metadata to be populated is empty.")
+
+    self._validate_metadata(metadata_buf)
+
+    # Gets the minimum metadata parser version of the metadata_buf.
+    min_version = _pywrap_metadata_version.GetMinimumMetadataParserVersion(
+        bytes(metadata_buf))
+
+    # Inserts in the minimum metadata parser version into the metadata_buf.
+    metadata = _metadata_fb.ModelMetadataT.InitFromObj(
+        _metadata_fb.ModelMetadata.GetRootAsModelMetadata(metadata_buf, 0))
+    metadata.minParserVersion = min_version
+
+    # Remove local file directory in the `name` field of `AssociatedFileT`, and
+    # make it consistent with the name of the actual file packed in the model.
+    self._use_basename_for_associated_files_in_metadata(metadata)
+
+    b = flatbuffers.Builder(0)
+    b.Finish(metadata.Pack(b), self.METADATA_FILE_IDENTIFIER)
+    metadata_buf_with_version = b.Output()
+
+    self._metadata_buf = metadata_buf_with_version
+
+  def load_metadata_file(self, metadata_file):
+    """Loads the metadata file to be populated.
+
+    Args:
+      metadata_file: path to the metadata file to be populated.
+
+    Raises:
+      IOError: File not found.
+      ValueError: The metadata to be populated is empty.
+      ValueError: The metadata does not have the expected flatbuffer identifer.
+      ValueError: Cannot get minimum metadata parser version.
+      ValueError: The number of SubgraphMetadata is not 1.
+      ValueError: The number of input/output tensors does not match the number
+        of input/output tensor metadata.
+    """
+    _assert_file_exist(metadata_file)
+    with _open_file(metadata_file, "rb") as f:
+      metadata_buf = f.read()
+    self.load_metadata_buffer(bytearray(metadata_buf))
+
+  def load_metadata_and_associated_files(self, src_model_buf):
+    """Loads the metadata and associated files from another model buffer.
+
+    Args:
+      src_model_buf: source model buffer (in bytearray) with metadata and
+        associated files.
+    """
+    # Load the model metadata from src_model_buf if exist.
+    metadata_buffer = get_metadata_buffer(src_model_buf)
+    if metadata_buffer:
+      self.load_metadata_buffer(metadata_buffer)
+
+    # Load the associated files from src_model_buf if exist.
+    if _is_zipfile(io.BytesIO(src_model_buf)):
+      with _open_as_zipfile(io.BytesIO(src_model_buf)) as zf:
+        self.load_associated_file_buffers(
+            {f: zf.read(f) for f in zf.namelist()})
+
+  def populate(self):
+    """Populates loaded metadata and associated files into the model file."""
+    self._assert_validate()
+    self._populate_metadata_buffer()
+    self._populate_associated_files()
+
+  def _assert_validate(self):
+    """Validates the metadata and associated files to be populated.
+
+    Raises:
+      ValueError:
+        File is recorded in the metadata, but is not going to be populated.
+        File has already been packed.
+    """
+    # Gets files that are recorded in metadata.
+    recorded_files = self.get_recorded_associated_file_list()
+
+    # Gets files that have been packed to self._model_file.
+    packed_files = self.get_packed_associated_file_list()
+
+    # Gets the file name of those associated files to be populated.
+    to_be_populated_files = self._associated_files.keys()
+
+    # Checks all files recorded in the metadata will be populated.
+    for rf in recorded_files:
+      if rf not in to_be_populated_files and rf not in packed_files:
+        raise ValueError("File, '{0}', is recorded in the metadata, but has "
+                         "not been loaded into the populator.".format(rf))
+
+    for f in to_be_populated_files:
+      if f in packed_files:
+        raise ValueError("File, '{0}', has already been packed.".format(f))
+
+      if f not in recorded_files:
+        warnings.warn(
+            "File, '{0}', does not exist in the metadata. But packing it to "
+            "tflite model is still allowed.".format(f))
+
+  def _copy_archived_files(self, src_zip, file_list, dst_zip):
+    """Copy archieved files in file_list from src_zip ro dst_zip."""
+
+    if not _is_zipfile(src_zip):
+      raise ValueError("File, '{0}', is not a zipfile.".format(src_zip))
+
+    with _open_as_zipfile(src_zip, "r") as src_zf, \
+         _open_as_zipfile(dst_zip, "a") as dst_zf:
+      src_list = src_zf.namelist()
+      for f in file_list:
+        if f not in src_list:
+          raise ValueError(
+              "File, '{0}', does not exist in the zipfile, {1}.".format(
+                  f, src_zip))
+        file_buffer = src_zf.read(f)
+        dst_zf.writestr(f, file_buffer)
+
+  def _get_associated_files_from_process_units(self, table, field_name):
+    """Gets the files that are attached the process units field of a table.
+
+    Args:
+      table: a Flatbuffers table object that contains fields of an array of
+        ProcessUnit, such as TensorMetadata and SubGraphMetadata.
+      field_name: the name of the field in the table that represents an array of
+        ProcessUnit. If the table is TensorMetadata, field_name can be
+        "ProcessUnits". If the table is SubGraphMetadata, field_name can be
+        either "InputProcessUnits" or "OutputProcessUnits".
+
+    Returns:
+      A list of AssociatedFileT objects.
+    """
+
+    if table is None:
+      return []
+
+    file_list = []
+    process_units = getattr(table, field_name)
+    # If the process_units field is not populated, it will be None. Use an
+    # empty list to skip the check.
+    for process_unit in process_units or []:
+      options = process_unit.options
+      if isinstance(options, (_metadata_fb.BertTokenizerOptionsT,
+                              _metadata_fb.RegexTokenizerOptionsT)):
+        file_list += self._get_associated_files_from_table(options, "vocabFile")
+      elif isinstance(options, _metadata_fb.SentencePieceTokenizerOptionsT):
+        file_list += self._get_associated_files_from_table(
+            options, "sentencePieceModel")
+        file_list += self._get_associated_files_from_table(options, "vocabFile")
+    return file_list
+
+  def _get_associated_files_from_table(self, table, field_name):
+    """Gets the associated files that are attached a table directly.
+
+    Args:
+      table: a Flatbuffers table object that contains fields of an array of
+        AssociatedFile, such as TensorMetadata and BertTokenizerOptions.
+      field_name: the name of the field in the table that represents an array of
+        ProcessUnit. If the table is TensorMetadata, field_name can be
+        "AssociatedFiles". If the table is BertTokenizerOptions, field_name can
+        be "VocabFile".
+
+    Returns:
+      A list of AssociatedFileT objects.
+    """
+
+    if table is None:
+      return []
+
+    # If the associated file field is not populated,
+    # `getattr(table, field_name)` will be None. Return an empty list.
+    return getattr(table, field_name) or []
+
+  def _get_recorded_associated_file_object_list(self, metadata):
+    """Gets a list of AssociatedFileT objects recorded in the metadata.
+
+    Associated files may be attached to a model, a subgraph, or an input/output
+    tensor.
+
+    Args:
+      metadata: the ModelMetadataT object.
+
+    Returns:
+      List of recorded AssociatedFileT objects.
+    """
+    recorded_files = []
+
+    # Add associated files attached to ModelMetadata.
+    recorded_files += self._get_associated_files_from_table(
+        metadata, "associatedFiles")
+
+    # Add associated files attached to each SubgraphMetadata.
+    for subgraph in metadata.subgraphMetadata or []:
+      recorded_files += self._get_associated_files_from_table(
+          subgraph, "associatedFiles")
+
+      # Add associated files attached to each input tensor.
+      for tensor_metadata in subgraph.inputTensorMetadata or []:
+        recorded_files += self._get_associated_files_from_table(
+            tensor_metadata, "associatedFiles")
+        recorded_files += self._get_associated_files_from_process_units(
+            tensor_metadata, "processUnits")
+
+      # Add associated files attached to each output tensor.
+      for tensor_metadata in subgraph.outputTensorMetadata or []:
+        recorded_files += self._get_associated_files_from_table(
+            tensor_metadata, "associatedFiles")
+        recorded_files += self._get_associated_files_from_process_units(
+            tensor_metadata, "processUnits")
+
+      # Add associated files attached to the input_process_units.
+      recorded_files += self._get_associated_files_from_process_units(
+          subgraph, "inputProcessUnits")
+
+      # Add associated files attached to the output_process_units.
+      recorded_files += self._get_associated_files_from_process_units(
+          subgraph, "outputProcessUnits")
+
+    return recorded_files
+
+  def _populate_associated_files(self):
+    """Concatenates associated files after TensorFlow Lite model file.
+
+    If the MetadataPopulator object is created using the method,
+    with_model_file(model_file), the model file will be updated.
+    """
+    # Opens up the model file in "appending" mode.
+    # If self._model_file already has pack files, zipfile will concatenate
+    # addition files after self._model_file. For example, suppose we have
+    # self._model_file = old_tflite_file | label1.txt | label2.txt
+    # Then after trigger populate() to add label3.txt, self._model_file becomes
+    # self._model_file = old_tflite_file | label1.txt | label2.txt | label3.txt
+    with tempfile.SpooledTemporaryFile() as temp:
+      # (1) Copy content from model file of to temp file.
+      with _open_file(self._model_file, "rb") as f:
+        shutil.copyfileobj(f, temp)
+
+      # (2) Append of to a temp file as a zip.
+      with _open_as_zipfile(temp, "a") as zf:
+        for file_name, file_buffer in self._associated_files.items():
+          zf.writestr(file_name, file_buffer)
+
+      # (3) Copy temp file to model file.
+      temp.seek(0)
+      with _open_file(self._model_file, "wb") as f:
+        shutil.copyfileobj(temp, f)
+
+  def _populate_metadata_buffer(self):
+    """Populates the metadata buffer (in bytearray) into the model file.
+
+    Inserts metadata_buf into the metadata field of schema.Model. If the
+    MetadataPopulator object is created using the method,
+    with_model_file(model_file), the model file will be updated.
+
+    Existing metadata buffer (if applied) will be overridden by the new metadata
+    buffer.
+    """
+
+    with _open_file(self._model_file, "rb") as f:
+      model_buf = f.read()
+
+    model = _schema_fb.ModelT.InitFromObj(
+        _schema_fb.Model.GetRootAsModel(model_buf, 0))
+    buffer_field = _schema_fb.BufferT()
+    buffer_field.data = self._metadata_buf
+
+    is_populated = False
+    if not model.metadata:
+      model.metadata = []
+    else:
+      # Check if metadata has already been populated.
+      for meta in model.metadata:
+        if meta.name.decode("utf-8") == self.METADATA_FIELD_NAME:
+          is_populated = True
+          model.buffers[meta.buffer] = buffer_field
+
+    if not is_populated:
+      if not model.buffers:
+        model.buffers = []
+      model.buffers.append(buffer_field)
+      # Creates a new metadata field.
+      metadata_field = _schema_fb.MetadataT()
+      metadata_field.name = self.METADATA_FIELD_NAME
+      metadata_field.buffer = len(model.buffers) - 1
+      model.metadata.append(metadata_field)
+
+    # Packs model back to a flatbuffer binaray file.
+    b = flatbuffers.Builder(0)
+    b.Finish(model.Pack(b), self.TFLITE_FILE_IDENTIFIER)
+    model_buf = b.Output()
+
+    # Saves the updated model buffer to model file.
+    # Gets files that have been packed to self._model_file.
+    packed_files = self.get_packed_associated_file_list()
+    if packed_files:
+      # Writes the updated model buffer and associated files into a new model
+      # file (in memory). Then overwrites the original model file.
+      with tempfile.SpooledTemporaryFile() as temp:
+        temp.write(model_buf)
+        self._copy_archived_files(self._model_file, packed_files, temp)
+        temp.seek(0)
+        with _open_file(self._model_file, "wb") as f:
+          shutil.copyfileobj(temp, f)
+    else:
+      with _open_file(self._model_file, "wb") as f:
+        f.write(model_buf)
+
+  def _use_basename_for_associated_files_in_metadata(self, metadata):
+    """Removes any associated file local directory (if exists)."""
+    for file in self._get_recorded_associated_file_object_list(metadata):
+      file.name = os.path.basename(file.name)
+
+  def _validate_metadata(self, metadata_buf):
+    """Validates the metadata to be populated."""
+    _assert_metadata_buffer_identifier(metadata_buf)
+
+    # Verify the number of SubgraphMetadata is exactly one.
+    # TFLite currently only support one subgraph.
+    model_meta = _metadata_fb.ModelMetadata.GetRootAsModelMetadata(
+        metadata_buf, 0)
+    if model_meta.SubgraphMetadataLength() != 1:
+      raise ValueError("The number of SubgraphMetadata should be exactly one, "
+                       "but got {0}.".format(
+                           model_meta.SubgraphMetadataLength()))
+
+    # Verify if the number of tensor metadata matches the number of tensors.
+    with _open_file(self._model_file, "rb") as f:
+      model_buf = f.read()
+    model = _schema_fb.Model.GetRootAsModel(model_buf, 0)
+
+    num_input_tensors = model.Subgraphs(0).InputsLength()
+    num_input_meta = model_meta.SubgraphMetadata(0).InputTensorMetadataLength()
+    if num_input_tensors != num_input_meta:
+      raise ValueError(
+          "The number of input tensors ({0}) should match the number of "
+          "input tensor metadata ({1})".format(num_input_tensors,
+                                               num_input_meta))
+    num_output_tensors = model.Subgraphs(0).OutputsLength()
+    num_output_meta = model_meta.SubgraphMetadata(
+        0).OutputTensorMetadataLength()
+    if num_output_tensors != num_output_meta:
+      raise ValueError(
+          "The number of output tensors ({0}) should match the number of "
+          "output tensor metadata ({1})".format(num_output_tensors,
+                                                num_output_meta))
+
+
+class _MetadataPopulatorWithBuffer(MetadataPopulator):
+  """Subclass of MetadtaPopulator that populates metadata to a model buffer.
+
+  This class is used to populate metadata into a in-memory model buffer. As we
+  use Zip API to concatenate associated files after tflite model file, the
+  populating operation is developed based on a model file. For in-memory model
+  buffer, we create a tempfile to serve the populating operation. This class is
+  then used to generate this tempfile, and delete the file when the
+  MetadataPopulator object is deleted.
+  """
+
+  def __init__(self, model_buf):
+    """Constructor for _MetadataPopulatorWithBuffer.
+
+    Args:
+      model_buf: TensorFlow Lite model buffer in bytearray.
+
+    Raises:
+      ValueError: model_buf is empty.
+      ValueError: model_buf does not have the expected flatbuffer identifer.
+    """
+    if not model_buf:
+      raise ValueError("model_buf cannot be empty.")
+
+    with tempfile.NamedTemporaryFile() as temp:
+      model_file = temp.name
+
+    with _open_file(model_file, "wb") as f:
+      f.write(model_buf)
+
+    super().__init__(model_file)
+
+  def __del__(self):
+    """Destructor of _MetadataPopulatorWithBuffer.
+
+    Deletes the tempfile.
+    """
+    if os.path.exists(self._model_file):
+      os.remove(self._model_file)
+
+
+class MetadataDisplayer(object):
+  """Displays metadata and associated file info in human-readable format."""
+
+  def __init__(self, model_buffer, metadata_buffer, associated_file_list):
+    """Constructor for MetadataDisplayer.
+
+    Args:
+      model_buffer: valid buffer of the model file.
+      metadata_buffer: valid buffer of the metadata file.
+      associated_file_list: list of associate files in the model file.
+    """
+    _assert_model_buffer_identifier(model_buffer)
+    _assert_metadata_buffer_identifier(metadata_buffer)
+    self._model_buffer = model_buffer
+    self._metadata_buffer = metadata_buffer
+    self._associated_file_list = associated_file_list
+
+  @classmethod
+  def with_model_file(cls, model_file):
+    """Creates a MetadataDisplayer object for the model file.
+
+    Args:
+      model_file: valid path to a TensorFlow Lite model file.
+
+    Returns:
+      MetadataDisplayer object.
+
+    Raises:
+      IOError: File not found.
+      ValueError: The model does not have metadata.
+    """
+    _assert_file_exist(model_file)
+    with _open_file(model_file, "rb") as f:
+      return cls.with_model_buffer(f.read())
+
+  @classmethod
+  def with_model_buffer(cls, model_buffer):
+    """Creates a MetadataDisplayer object for a file buffer.
+
+    Args:
+      model_buffer: TensorFlow Lite model buffer in bytearray.
+
+    Returns:
+      MetadataDisplayer object.
+    """
+    if not model_buffer:
+      raise ValueError("model_buffer cannot be empty.")
+    metadata_buffer = get_metadata_buffer(model_buffer)
+    if not metadata_buffer:
+      raise ValueError("The model does not have metadata.")
+    associated_file_list = cls._parse_packed_associted_file_list(model_buffer)
+    return cls(model_buffer, metadata_buffer, associated_file_list)
+
+  def get_associated_file_buffer(self, filename):
+    """Get the specified associated file content in bytearray.
+
+    Args:
+      filename: name of the file to be extracted.
+
+    Returns:
+      The file content in bytearray.
+
+    Raises:
+      ValueError: if the file does not exist in the model.
+    """
+    if filename not in self._associated_file_list:
+      raise ValueError(
+          "The file, {}, does not exist in the model.".format(filename))
+
+    with _open_as_zipfile(io.BytesIO(self._model_buffer)) as zf:
+      return zf.read(filename)
+
+  def get_metadata_buffer(self):
+    """Get the metadata buffer in bytearray out from the model."""
+    return copy.deepcopy(self._metadata_buffer)
+
+  def get_metadata_json(self):
+    """Converts the metadata into a json string."""
+    return convert_to_json(self._metadata_buffer)
+
+  def get_packed_associated_file_list(self):
+    """Returns a list of associated files that are packed in the model.
+
+    Returns:
+      A name list of associated files.
+    """
+    return copy.deepcopy(self._associated_file_list)
+
+  @staticmethod
+  def _parse_packed_associted_file_list(model_buf):
+    """Gets a list of associated files packed to the model file.
+
+    Args:
+      model_buf: valid file buffer.
+
+    Returns:
+      List of packed associated files.
+    """
+
+    try:
+      with _open_as_zipfile(io.BytesIO(model_buf)) as zf:
+        return zf.namelist()
+    except zipfile.BadZipFile:
+      return []
+
+
+# Create an individual method for getting the metadata json file, so that it can
+# be used as a standalone util.
+def convert_to_json(metadata_buffer):
+  """Converts the metadata into a json string.
+
+  Args:
+    metadata_buffer: valid metadata buffer in bytes.
+
+  Returns:
+    Metadata in JSON format.
+
+  Raises:
+    ValueError: error occured when parsing the metadata schema file.
+  """
+
+  opt = _pywrap_flatbuffers.IDLOptions()
+  opt.strict_json = True
+  parser = _pywrap_flatbuffers.Parser(opt)
+  with _open_file(_FLATC_TFLITE_METADATA_SCHEMA_FILE) as f:
+    metadata_schema_content = f.read()
+  if not parser.parse(metadata_schema_content):
+    raise ValueError("Cannot parse metadata schema. Reason: " + parser.error)
+  return _pywrap_flatbuffers.generate_text(parser, metadata_buffer)
+
+
+def _assert_file_exist(filename):
+  """Checks if a file exists."""
+  if not _exists_file(filename):
+    raise IOError("File, '{0}', does not exist.".format(filename))
+
+
+def _assert_model_file_identifier(model_file):
+  """Checks if a model file has the expected TFLite schema identifier."""
+  _assert_file_exist(model_file)
+  with _open_file(model_file, "rb") as f:
+    _assert_model_buffer_identifier(f.read())
+
+
+def _assert_model_buffer_identifier(model_buf):
+  if not _schema_fb.Model.ModelBufferHasIdentifier(model_buf, 0):
+    raise ValueError(
+        "The model provided does not have the expected identifier, and "
+        "may not be a valid TFLite model.")
+
+
+def _assert_metadata_buffer_identifier(metadata_buf):
+  """Checks if a metadata buffer has the expected Metadata schema identifier."""
+  if not _metadata_fb.ModelMetadata.ModelMetadataBufferHasIdentifier(
+      metadata_buf, 0):
+    raise ValueError(
+        "The metadata buffer does not have the expected identifier, and may not"
+        " be a valid TFLite Metadata.")
+
+
+def get_metadata_buffer(model_buf):
+  """Returns the metadata in the model file as a buffer.
+
+  Args:
+    model_buf: valid buffer of the model file.
+
+  Returns:
+    Metadata buffer. Returns `None` if the model does not have metadata.
+  """
+  tflite_model = _schema_fb.Model.GetRootAsModel(model_buf, 0)
+
+  # Gets metadata from the model file.
+  for i in range(tflite_model.MetadataLength()):
+    meta = tflite_model.Metadata(i)
+    if meta.Name().decode("utf-8") == MetadataPopulator.METADATA_FIELD_NAME:
+      buffer_index = meta.Buffer()
+      metadata = tflite_model.Buffers(buffer_index)
+      return metadata.DataAsNumpy().tobytes()
+
+  return None

mediapipe/tasks/python/metadata/metadata_displayer_cli.py

@@ -0,0 +1,34 @@
+# Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+"""CLI tool for display metadata."""
+
+from absl import app
+from absl import flags
+
+from mediapipe.tasks.python.metadata import metadata
+
+FLAGS = flags.FLAGS
+flags.DEFINE_string('model_path', None, 'Path to the TFLite model file.')
+flags.DEFINE_string('export_json_path', None, 'Path to the output JSON file.')
+
+
+def main(_):
+  displayer = metadata.MetadataDisplayer.with_model_file(FLAGS.model_path)
+  with open(FLAGS.export_json_path, 'w') as f:
+    f.write(displayer.get_metadata_json())
+
+
+if __name__ == '__main__':
+  app.run(main)