Project import generated by Copybara.

GitOrigin-RevId: 43cd697ec87dcc5cab5051f27960bb77a057399d

WORKSPACE

@@ -129,7 +129,11 @@ http_archive(
     ],
     # A compatibility patch
     patches = [
-        "@//third_party:org_tensorflow_528e22eae8bf3206189a066032c66e9e5c9b4a61.diff"
+        "@//third_party:org_tensorflow_528e22eae8bf3206189a066032c66e9e5c9b4a61.diff",
+        # Updates for XNNPACK: https://github.com/tensorflow/tensorflow/commit/cfc31e324c8de6b52f752a39cb161d99d853ca99
+        "@//third_party:org_tensorflow_cfc31e324c8de6b52f752a39cb161d99d853ca99.diff",
+        # CpuInfo's build rule fixes.
+        "@//third_party:org_tensorflow_9696366bcadab23a25c773b3ed405bac8ded4d0d.diff",
     ],
     patch_args = [
         "-p1",

mediapipe/calculators/core/BUILD

@@ -228,6 +228,7 @@ cc_library(
         "//mediapipe/framework:calculator_framework",
         "//mediapipe/framework:collection_item_id",
         "//mediapipe/framework:packet",
+        "//mediapipe/framework/formats:detection_cc_proto",
         "//mediapipe/framework/formats:landmark_cc_proto",
         "//mediapipe/framework/formats:rect_cc_proto",
         "//mediapipe/framework/port:integral_types",
@@ -249,6 +250,7 @@ cc_library(
         "//mediapipe/framework:calculator_framework",
         "//mediapipe/framework:collection_item_id",
         "//mediapipe/framework:packet",
+        "//mediapipe/framework/formats:classification_cc_proto",
         "//mediapipe/framework/formats:landmark_cc_proto",
         "//mediapipe/framework/formats:rect_cc_proto",
         "//mediapipe/framework/port:integral_types",
@@ -265,10 +267,11 @@ cc_test(
     deps = [
         ":begin_loop_calculator",
         ":end_loop_calculator",
-        "//mediapipe/calculators/core:packet_cloner_calculator",
+        ":gate_calculator",
         "//mediapipe/framework:calculator_context",
         "//mediapipe/framework:calculator_contract",
         "//mediapipe/framework:calculator_framework",
+        "//mediapipe/framework:packet",
         "//mediapipe/framework/port:gtest_main",
         "//mediapipe/framework/port:integral_types",
         "//mediapipe/framework/port:parse_text_proto",
@@ -334,6 +337,7 @@ cc_library(
     deps = [
         ":clip_vector_size_calculator_cc_proto",
         "//mediapipe/framework:calculator_framework",
+        "//mediapipe/framework/formats:detection_cc_proto",
         "//mediapipe/framework/formats:rect_cc_proto",
         "//mediapipe/framework/port:ret_check",
         "//mediapipe/framework/port:status",
@@ -693,15 +697,17 @@ cc_test(
     name = "previous_loopback_calculator_test",
     srcs = ["previous_loopback_calculator_test.cc"],
     deps = [
+        ":gate_calculator",
+        ":make_pair_calculator",
+        ":pass_through_calculator",
         ":previous_loopback_calculator",
-        "//mediapipe/calculators/core:make_pair_calculator",
-        "//mediapipe/calculators/core:pass_through_calculator",
         "//mediapipe/framework:calculator_framework",
         "//mediapipe/framework:calculator_runner",
         "//mediapipe/framework:timestamp",
         "//mediapipe/framework/port:gtest_main",
         "//mediapipe/framework/port:integral_types",
         "//mediapipe/framework/port:parse_text_proto",
+        "//mediapipe/framework/port:status",
         "//mediapipe/framework/stream_handler:immediate_input_stream_handler",
         "//mediapipe/framework/tool:sink",
         "@com_google_absl//absl/time",
@@ -769,6 +775,7 @@ cc_library(
     visibility = ["//visibility:public"],
     deps = [
         ":split_vector_calculator_cc_proto",
+        "//mediapipe/framework/formats:detection_cc_proto",
         "//mediapipe/framework:calculator_framework",
         "//mediapipe/framework/formats:landmark_cc_proto",
         "//mediapipe/framework/formats:rect_cc_proto",

mediapipe/calculators/core/begin_end_loop_calculator_graph_test.cc

@@ -20,6 +20,8 @@
 #include "mediapipe/calculators/core/end_loop_calculator.h"
 #include "mediapipe/framework/calculator_contract.h"
 #include "mediapipe/framework/calculator_framework.h"
+#include "mediapipe/framework/packet.h"
+#include "mediapipe/framework/port/gmock.h"
 #include "mediapipe/framework/port/gtest.h"
 #include "mediapipe/framework/port/integral_types.h"
 #include "mediapipe/framework/port/parse_text_proto.h"
@@ -28,6 +30,13 @@
 namespace mediapipe {
 namespace {
 
+MATCHER_P2(PacketOfIntsEq, timestamp, value, "") {
+  Timestamp actual_timestamp = arg.Timestamp();
+  const auto& actual_value = arg.template Get<std::vector<int>>();
+  return testing::Value(actual_timestamp, testing::Eq(timestamp)) &&
+         testing::Value(actual_value, testing::ElementsAreArray(value));
+}
+
 typedef BeginLoopCalculator<std::vector<int>> BeginLoopIntegerCalculator;
 REGISTER_CALCULATOR(BeginLoopIntegerCalculator);
 
@@ -59,8 +68,8 @@ REGISTER_CALCULATOR(EndLoopIntegersCalculator);
 
 class BeginEndLoopCalculatorGraphTest : public ::testing::Test {
  protected:
-  BeginEndLoopCalculatorGraphTest() {
+  void SetUp() override {
-    graph_config_ = ParseTextProtoOrDie<CalculatorGraphConfig>(
+    auto graph_config = ParseTextProtoOrDie<CalculatorGraphConfig>(
         R"(
           num_threads: 4
           input_stream: "ints"
@@ -82,94 +91,222 @@ class BeginEndLoopCalculatorGraphTest : public ::testing::Test {
             output_stream: "ITERABLE:ints_plus_one"
           }
         )");
-    tool::AddVectorSink("ints_plus_one", &graph_config_, &output_packets_);
+    tool::AddVectorSink("ints_plus_one", &graph_config, &output_packets_);
+    MP_ASSERT_OK(graph_.Initialize(graph_config));
+    MP_ASSERT_OK(graph_.StartRun({}));
   }
 
-  CalculatorGraphConfig graph_config_;
+  void SendPacketOfInts(Timestamp timestamp, std::vector<int> ints) {
+    MP_ASSERT_OK(graph_.AddPacketToInputStream(
+        "ints", MakePacket<std::vector<int>>(std::move(ints)).At(timestamp)));
+  }
+
+  CalculatorGraph graph_;
   std::vector<Packet> output_packets_;
 };
 
+TEST_F(BeginEndLoopCalculatorGraphTest, InputStreamForIterableIsEmpty) {
+  MP_ASSERT_OK(graph_.WaitUntilIdle());
+
+  // EndLoopCalc will forward the timestamp bound because there are no packets
+  // to process.
+  ASSERT_EQ(0, output_packets_.size());
+
+  MP_ASSERT_OK(graph_.CloseAllPacketSources());
+  MP_ASSERT_OK(graph_.WaitUntilDone());
+}
+
 TEST_F(BeginEndLoopCalculatorGraphTest, SingleEmptyVector) {
-  CalculatorGraph graph;
+  SendPacketOfInts(Timestamp(0), {});
-  MP_EXPECT_OK(graph.Initialize(graph_config_));
+  MP_ASSERT_OK(graph_.WaitUntilIdle());
-  MP_EXPECT_OK(graph.StartRun({}));
-  auto input_vector = absl::make_unique<std::vector<int>>();
-  Timestamp input_timestamp = Timestamp(0);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
-      "ints", Adopt(input_vector.release()).At(input_timestamp)));
-  MP_ASSERT_OK(graph.WaitUntilIdle());
 
   // EndLoopCalc will forward the timestamp bound because there are no elements
   // in collection to output.
-  ASSERT_EQ(0, output_packets_.size());
+  EXPECT_TRUE(output_packets_.empty());
 
-  MP_ASSERT_OK(graph.CloseAllPacketSources());
+  MP_ASSERT_OK(graph_.CloseAllPacketSources());
-  MP_ASSERT_OK(graph.WaitUntilDone());
+  MP_ASSERT_OK(graph_.WaitUntilDone());
 }
 
 TEST_F(BeginEndLoopCalculatorGraphTest, SingleNonEmptyVector) {
-  CalculatorGraph graph;
-  MP_EXPECT_OK(graph.Initialize(graph_config_));
-  MP_EXPECT_OK(graph.StartRun({}));
-  auto input_vector = absl::make_unique<std::vector<int>>();
-  input_vector->emplace_back(0);
-  input_vector->emplace_back(1);
-  input_vector->emplace_back(2);
   Timestamp input_timestamp = Timestamp(0);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
+  SendPacketOfInts(input_timestamp, {0, 1, 2});
-      "ints", Adopt(input_vector.release()).At(input_timestamp)));
+  MP_ASSERT_OK(graph_.WaitUntilIdle());
-  MP_ASSERT_OK(graph.WaitUntilIdle());
 
-  ASSERT_EQ(1, output_packets_.size());
+  EXPECT_THAT(output_packets_,
-  EXPECT_EQ(input_timestamp, output_packets_[0].Timestamp());
+              testing::ElementsAre(
-  std::vector<int> expected_output_vector = {1, 2, 3};
+                  PacketOfIntsEq(input_timestamp, std::vector<int>{1, 2, 3})));
-  EXPECT_EQ(expected_output_vector, output_packets_[0].Get<std::vector<int>>());
 
-  MP_ASSERT_OK(graph.CloseAllPacketSources());
+  MP_ASSERT_OK(graph_.CloseAllPacketSources());
-  MP_ASSERT_OK(graph.WaitUntilDone());
+  MP_ASSERT_OK(graph_.WaitUntilDone());
 }
 
 TEST_F(BeginEndLoopCalculatorGraphTest, MultipleVectors) {
-  CalculatorGraph graph;
-  MP_EXPECT_OK(graph.Initialize(graph_config_));
-  MP_EXPECT_OK(graph.StartRun({}));
-
-  auto input_vector0 = absl::make_unique<std::vector<int>>();
-  input_vector0->emplace_back(0);
-  input_vector0->emplace_back(1);
   Timestamp input_timestamp0 = Timestamp(0);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
+  SendPacketOfInts(input_timestamp0, {0, 1});
-      "ints", Adopt(input_vector0.release()).At(input_timestamp0)));
 
-  auto input_vector1 = absl::make_unique<std::vector<int>>();
   Timestamp input_timestamp1 = Timestamp(1);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
+  SendPacketOfInts(input_timestamp1, {});
-      "ints", Adopt(input_vector1.release()).At(input_timestamp1)));
 
-  auto input_vector2 = absl::make_unique<std::vector<int>>();
-  input_vector2->emplace_back(2);
-  input_vector2->emplace_back(3);
   Timestamp input_timestamp2 = Timestamp(2);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
+  SendPacketOfInts(input_timestamp2, {2, 3});
-      "ints", Adopt(input_vector2.release()).At(input_timestamp2)));
 
-  MP_ASSERT_OK(graph.CloseAllPacketSources());
+  MP_ASSERT_OK(graph_.CloseAllPacketSources());
-  MP_ASSERT_OK(graph.WaitUntilDone());
+  MP_ASSERT_OK(graph_.WaitUntilDone());
-
-  ASSERT_EQ(2, output_packets_.size());
-
-  EXPECT_EQ(input_timestamp0, output_packets_[0].Timestamp());
-  std::vector<int> expected_output_vector0 = {1, 2};
-  EXPECT_EQ(expected_output_vector0,
-            output_packets_[0].Get<std::vector<int>>());
 
   // At input_timestamp1, EndLoopCalc will forward timestamp bound as there are
   // no elements in vector to process.
+  EXPECT_THAT(output_packets_,
+              testing::ElementsAre(
+                  PacketOfIntsEq(input_timestamp0, std::vector<int>{1, 2}),
+                  PacketOfIntsEq(input_timestamp2, std::vector<int>{3, 4})));
+}
 
-  EXPECT_EQ(input_timestamp2, output_packets_[1].Timestamp());
+// Passes non empty vector through or outputs empty vector in case of timestamp
-  std::vector<int> expected_output_vector2 = {3, 4};
+// bound update.
-  EXPECT_EQ(expected_output_vector2,
+class PassThroughOrEmptyVectorCalculator : public CalculatorBase {
-            output_packets_[1].Get<std::vector<int>>());
+ public:
+  static ::mediapipe::Status GetContract(CalculatorContract* cc) {
+    cc->SetProcessTimestampBounds(true);
+    cc->Inputs().Index(0).Set<std::vector<int>>();
+    cc->Outputs().Index(0).Set<std::vector<int>>();
+    return ::mediapipe::OkStatus();
+  }
+
+  ::mediapipe::Status Open(CalculatorContext* cc) override {
+    cc->SetOffset(TimestampDiff(0));
+    return ::mediapipe::OkStatus();
+  }
+
+  ::mediapipe::Status Process(CalculatorContext* cc) override {
+    if (!cc->Inputs().Index(0).IsEmpty()) {
+      cc->Outputs().Index(0).AddPacket(cc->Inputs().Index(0).Value());
+    } else {
+      cc->Outputs().Index(0).AddPacket(
+          MakePacket<std::vector<int>>(std::vector<int>())
+              .At(cc->InputTimestamp()));
+    }
+    return ::mediapipe::OkStatus();
+  }
+};
+
+REGISTER_CALCULATOR(PassThroughOrEmptyVectorCalculator);
+
+class BeginEndLoopCalculatorGraphProcessingEmptyPacketsTest
+    : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    auto graph_config = ParseTextProtoOrDie<CalculatorGraphConfig>(
+        R"(
+          num_threads: 4
+          input_stream: "ints"
+          input_stream: "force_ints_to_be_timestamp_bound_update"
+          node {
+            calculator: "GateCalculator"
+            input_stream: "ints"
+            input_stream: "DISALLOW:force_ints_to_be_timestamp_bound_update"
+            output_stream: "ints_passed_through"
+          }
+          node {
+            calculator: "BeginLoopIntegerCalculator"
+            input_stream: "ITERABLE:ints_passed_through"
+            output_stream: "ITEM:int"
+            output_stream: "BATCH_END:timestamp"
+          }
+          node {
+            calculator: "IncrementCalculator"
+            input_stream: "int"
+            output_stream: "int_plus_one"
+          }
+          node {
+            calculator: "EndLoopIntegersCalculator"
+            input_stream: "ITEM:int_plus_one"
+            input_stream: "BATCH_END:timestamp"
+            output_stream: "ITERABLE:ints_plus_one"
+          }
+          node {
+            calculator: "PassThroughOrEmptyVectorCalculator"
+            input_stream: "ints_plus_one"
+            output_stream: "ints_plus_one_passed_through"
+          }
+        )");
+    tool::AddVectorSink("ints_plus_one_passed_through", &graph_config,
+                        &output_packets_);
+    MP_ASSERT_OK(graph_.Initialize(graph_config));
+    MP_ASSERT_OK(graph_.StartRun({}));
+  }
+
+  void SendPacketOfIntsOrBound(Timestamp timestamp, std::vector<int> ints) {
+    // All "ints" packets which are empty are forced to be just timestamp
+    // bound updates for begin loop calculator.
+    bool force_ints_to_be_timestamp_bound_update = ints.empty();
+    MP_ASSERT_OK(graph_.AddPacketToInputStream(
+        "force_ints_to_be_timestamp_bound_update",
+        MakePacket<bool>(force_ints_to_be_timestamp_bound_update)
+            .At(timestamp)));
+    MP_ASSERT_OK(graph_.AddPacketToInputStream(
+        "ints", MakePacket<std::vector<int>>(std::move(ints)).At(timestamp)));
+  }
+
+  CalculatorGraph graph_;
+  std::vector<Packet> output_packets_;
+};
+
+TEST_F(BeginEndLoopCalculatorGraphProcessingEmptyPacketsTest,
+       SingleEmptyVector) {
+  SendPacketOfIntsOrBound(Timestamp(0), {});
+  MP_ASSERT_OK(graph_.WaitUntilIdle());
+
+  EXPECT_THAT(output_packets_, testing::ElementsAre(PacketOfIntsEq(
+                                   Timestamp(0), std::vector<int>{})));
+
+  MP_ASSERT_OK(graph_.CloseAllPacketSources());
+  MP_ASSERT_OK(graph_.WaitUntilDone());
+}
+
+TEST_F(BeginEndLoopCalculatorGraphProcessingEmptyPacketsTest,
+       SingleNonEmptyVector) {
+  SendPacketOfIntsOrBound(Timestamp(0), {0, 1, 2});
+  MP_ASSERT_OK(graph_.WaitUntilIdle());
+
+  EXPECT_THAT(output_packets_, testing::ElementsAre(PacketOfIntsEq(
+                                   Timestamp(0), std::vector<int>{1, 2, 3})));
+
+  MP_ASSERT_OK(graph_.CloseAllPacketSources());
+  MP_ASSERT_OK(graph_.WaitUntilDone());
+}
+
+TEST_F(BeginEndLoopCalculatorGraphProcessingEmptyPacketsTest, MultipleVectors) {
+  SendPacketOfIntsOrBound(Timestamp(0), {});
+  // Waiting until idle to guarantee all timestamp bound updates are processed
+  // individually. (Timestamp bounds updates occur in the provide config only
+  // if input is an empty vector.)
+  MP_ASSERT_OK(graph_.WaitUntilIdle());
+
+  SendPacketOfIntsOrBound(Timestamp(1), {0, 1});
+  SendPacketOfIntsOrBound(Timestamp(2), {});
+  // Waiting until idle to guarantee all timestamp bound updates are processed
+  // individually. (Timestamp bounds updates occur in the provide config only
+  // if input is an empty vector.)
+  MP_ASSERT_OK(graph_.WaitUntilIdle());
+
+  SendPacketOfIntsOrBound(Timestamp(3), {2, 3});
+  SendPacketOfIntsOrBound(Timestamp(4), {});
+  // Waiting until idle to guarantee all timestamp bound updates are processed
+  // individually. (Timestamp bounds updates occur in the provide config only
+  // if input is an empty vector.)
+  MP_ASSERT_OK(graph_.WaitUntilIdle());
+
+  MP_ASSERT_OK(graph_.CloseAllPacketSources());
+  MP_ASSERT_OK(graph_.WaitUntilDone());
+
+  EXPECT_THAT(
+      output_packets_,
+      testing::ElementsAre(PacketOfIntsEq(Timestamp(0), std::vector<int>{}),
+                           PacketOfIntsEq(Timestamp(1), std::vector<int>{1, 2}),
+                           PacketOfIntsEq(Timestamp(2), std::vector<int>{}),
+                           PacketOfIntsEq(Timestamp(3), std::vector<int>{3, 4}),
+                           PacketOfIntsEq(Timestamp(4), std::vector<int>{})));
 }
 
 class MultiplierCalculator : public CalculatorBase {
@@ -199,8 +336,8 @@ REGISTER_CALCULATOR(MultiplierCalculator);
 
 class BeginEndLoopCalculatorGraphWithClonedInputsTest : public ::testing::Test {
  protected:
-  BeginEndLoopCalculatorGraphWithClonedInputsTest() {
+  void SetUp() override {
-    graph_config_ = ParseTextProtoOrDie<CalculatorGraphConfig>(
+    auto graph_config = ParseTextProtoOrDie<CalculatorGraphConfig>(
         R"(
           num_threads: 4
           input_stream: "ints"
@@ -226,109 +363,85 @@ class BeginEndLoopCalculatorGraphWithClonedInputsTest : public ::testing::Test {
             output_stream: "ITERABLE:multiplied_ints"
           }
         )");
-    tool::AddVectorSink("multiplied_ints", &graph_config_, &output_packets_);
+    tool::AddVectorSink("multiplied_ints", &graph_config, &output_packets_);
+    MP_ASSERT_OK(graph_.Initialize(graph_config));
+    MP_ASSERT_OK(graph_.StartRun({}));
   }
 
-  CalculatorGraphConfig graph_config_;
+  void SendPackets(Timestamp timestamp, int multiplier, std::vector<int> ints) {
+    MP_ASSERT_OK(graph_.AddPacketToInputStream(
+        "ints", MakePacket<std::vector<int>>(std::move(ints)).At(timestamp)));
+    MP_ASSERT_OK(graph_.AddPacketToInputStream(
+        "multiplier", MakePacket<int>(multiplier).At(timestamp)));
+  }
+
+  void SendMultiplier(Timestamp timestamp, int multiplier) {
+    MP_ASSERT_OK(graph_.AddPacketToInputStream(
+        "multiplier", MakePacket<int>(multiplier).At(timestamp)));
+  }
+
+  CalculatorGraph graph_;
   std::vector<Packet> output_packets_;
 };
 
-TEST_F(BeginEndLoopCalculatorGraphWithClonedInputsTest, SingleEmptyVector) {
+TEST_F(BeginEndLoopCalculatorGraphWithClonedInputsTest,
-  CalculatorGraph graph;
+       InputStreamForIterableIsEmpty) {
-  MP_EXPECT_OK(graph.Initialize(graph_config_));
-  MP_EXPECT_OK(graph.StartRun({}));
-  auto input_vector = absl::make_unique<std::vector<int>>();
   Timestamp input_timestamp = Timestamp(42);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
+  SendMultiplier(input_timestamp, /*multiplier=*/2);
-      "ints", Adopt(input_vector.release()).At(input_timestamp)));
+  MP_ASSERT_OK(graph_.WaitUntilIdle());
-  auto multiplier = absl::make_unique<int>(2);
+
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
+  // EndLoopCalc will forward the timestamp bound because there are no packets
-      "multiplier", Adopt(multiplier.release()).At(input_timestamp)));
+  // to process.
-  MP_ASSERT_OK(graph.WaitUntilIdle());
+  ASSERT_EQ(0, output_packets_.size());
+
+  MP_ASSERT_OK(graph_.CloseAllPacketSources());
+  MP_ASSERT_OK(graph_.WaitUntilDone());
+}
+
+TEST_F(BeginEndLoopCalculatorGraphWithClonedInputsTest, SingleEmptyVector) {
+  SendPackets(Timestamp(0), /*multiplier=*/2, /*ints=*/{});
+  MP_ASSERT_OK(graph_.WaitUntilIdle());
 
   // EndLoopCalc will forward the timestamp bound because there are no elements
   // in collection to output.
-  ASSERT_EQ(0, output_packets_.size());
+  EXPECT_TRUE(output_packets_.empty());
 
-  MP_ASSERT_OK(graph.CloseAllPacketSources());
+  MP_ASSERT_OK(graph_.CloseAllPacketSources());
-  MP_ASSERT_OK(graph.WaitUntilDone());
+  MP_ASSERT_OK(graph_.WaitUntilDone());
 }
 
 TEST_F(BeginEndLoopCalculatorGraphWithClonedInputsTest, SingleNonEmptyVector) {
-  CalculatorGraph graph;
-  MP_EXPECT_OK(graph.Initialize(graph_config_));
-  MP_EXPECT_OK(graph.StartRun({}));
-  auto input_vector = absl::make_unique<std::vector<int>>();
-  input_vector->emplace_back(0);
-  input_vector->emplace_back(1);
-  input_vector->emplace_back(2);
   Timestamp input_timestamp = Timestamp(42);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
+  SendPackets(input_timestamp, /*multiplier=*/2, /*ints=*/{0, 1, 2});
-      "ints", Adopt(input_vector.release()).At(input_timestamp)));
+  MP_ASSERT_OK(graph_.WaitUntilIdle());
-  auto multiplier = absl::make_unique<int>(2);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
-      "multiplier", Adopt(multiplier.release()).At(input_timestamp)));
-  MP_ASSERT_OK(graph.WaitUntilIdle());
 
-  ASSERT_EQ(1, output_packets_.size());
+  EXPECT_THAT(output_packets_,
-  EXPECT_EQ(input_timestamp, output_packets_[0].Timestamp());
+              testing::ElementsAre(
-  std::vector<int> expected_output_vector = {0, 2, 4};
+                  PacketOfIntsEq(input_timestamp, std::vector<int>{0, 2, 4})));
-  EXPECT_EQ(expected_output_vector, output_packets_[0].Get<std::vector<int>>());
 
-  MP_ASSERT_OK(graph.CloseAllPacketSources());
+  MP_ASSERT_OK(graph_.CloseAllPacketSources());
-  MP_ASSERT_OK(graph.WaitUntilDone());
+  MP_ASSERT_OK(graph_.WaitUntilDone());
 }
 
 TEST_F(BeginEndLoopCalculatorGraphWithClonedInputsTest, MultipleVectors) {
-  CalculatorGraph graph;
-  MP_EXPECT_OK(graph.Initialize(graph_config_));
-  MP_EXPECT_OK(graph.StartRun({}));
-
-  auto input_vector0 = absl::make_unique<std::vector<int>>();
-  input_vector0->emplace_back(0);
-  input_vector0->emplace_back(1);
   Timestamp input_timestamp0 = Timestamp(42);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
+  SendPackets(input_timestamp0, /*multiplier=*/2, /*ints=*/{0, 1});
-      "ints", Adopt(input_vector0.release()).At(input_timestamp0)));
-  auto multiplier0 = absl::make_unique<int>(2);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
-      "multiplier", Adopt(multiplier0.release()).At(input_timestamp0)));
 
-  auto input_vector1 = absl::make_unique<std::vector<int>>();
   Timestamp input_timestamp1 = Timestamp(43);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
+  SendPackets(input_timestamp1, /*multiplier=*/2, /*ints=*/{});
-      "ints", Adopt(input_vector1.release()).At(input_timestamp1)));
-  auto multiplier1 = absl::make_unique<int>(2);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
-      "multiplier", Adopt(multiplier1.release()).At(input_timestamp1)));
 
-  auto input_vector2 = absl::make_unique<std::vector<int>>();
-  input_vector2->emplace_back(2);
-  input_vector2->emplace_back(3);
   Timestamp input_timestamp2 = Timestamp(44);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
+  SendPackets(input_timestamp2, /*multiplier=*/3, /*ints=*/{2, 3});
-      "ints", Adopt(input_vector2.release()).At(input_timestamp2)));
-  auto multiplier2 = absl::make_unique<int>(3);
-  MP_ASSERT_OK(graph.AddPacketToInputStream(
-      "multiplier", Adopt(multiplier2.release()).At(input_timestamp2)));
 
-  MP_ASSERT_OK(graph.CloseAllPacketSources());
+  MP_ASSERT_OK(graph_.CloseAllPacketSources());
-  MP_ASSERT_OK(graph.WaitUntilDone());
+  MP_ASSERT_OK(graph_.WaitUntilDone());
-
-  ASSERT_EQ(2, output_packets_.size());
-
-  EXPECT_EQ(input_timestamp0, output_packets_[0].Timestamp());
-  std::vector<int> expected_output_vector0 = {0, 2};
-  EXPECT_EQ(expected_output_vector0,
-            output_packets_[0].Get<std::vector<int>>());
 
   // At input_timestamp1, EndLoopCalc will forward timestamp bound as there are
   // no elements in vector to process.
-
+  EXPECT_THAT(output_packets_,
-  EXPECT_EQ(input_timestamp2, output_packets_[1].Timestamp());
+              testing::ElementsAre(
-  std::vector<int> expected_output_vector2 = {6, 9};
+                  PacketOfIntsEq(input_timestamp0, std::vector<int>{0, 2}),
-  EXPECT_EQ(expected_output_vector2,
+                  PacketOfIntsEq(input_timestamp2, std::vector<int>{6, 9})));
-            output_packets_[1].Get<std::vector<int>>());
 }
 
 }  // namespace

mediapipe/calculators/core/begin_loop_calculator.cc

@@ -16,6 +16,7 @@
 
 #include <vector>
 
+#include "mediapipe/framework/formats/detection.pb.h"
 #include "mediapipe/framework/formats/landmark.pb.h"
 #include "mediapipe/framework/formats/rect.pb.h"
 
@@ -31,4 +32,9 @@ typedef BeginLoopCalculator<std::vector<::mediapipe::NormalizedRect>>
     BeginLoopNormalizedRectCalculator;
 REGISTER_CALCULATOR(BeginLoopNormalizedRectCalculator);
 
+// A calculator to process std::vector<Detection>.
+typedef BeginLoopCalculator<std::vector<::mediapipe::Detection>>
+    BeginLoopDetectionCalculator;
+REGISTER_CALCULATOR(BeginLoopDetectionCalculator);
+
 }  // namespace mediapipe

mediapipe/calculators/core/begin_loop_calculator.h

@@ -52,20 +52,28 @@ namespace mediapipe {
 //   output_stream: "OUTPUT:aggregated_result"     # IterableU @ext_ts
 // }
 //
-// BeginLoopCalculator accepts an optional input stream tagged with "TICK"
+// Input streams tagged with "CLONE" are cloned to the corresponding output
-// which if non-empty, wakes up the calculator and calls
+// streams at loop timestamps. This ensures that a MediaPipe graph or sub-graph
-// BeginLoopCalculator::Process(). Input streams tagged with "CLONE" are cloned
+// can run multiple times, once per element in the "ITERABLE" for each pakcet
-// to the corresponding output streams at loop timestamps. This ensures that a
+// clone of the packets in the "CLONE" input streams.
-// MediaPipe graph or sub-graph can run multiple times, once per element in the
-// "ITERABLE" for each pakcet clone of the packets in the "CLONE" input streams.
 template <typename IterableT>
 class BeginLoopCalculator : public CalculatorBase {
   using ItemT = typename IterableT::value_type;
 
  public:
   static ::mediapipe::Status GetContract(CalculatorContract* cc) {
+    // The below enables processing of timestamp bound updates, and that enables
+    // correct timestamp propagation by the companion EndLoopCalculator.
+    //
+    // For instance, Process() function will be still invoked even if upstream
+    // calculator has updated timestamp bound for ITERABLE input instead of
+    // providing actual value.
+    cc->SetProcessTimestampBounds(true);
+
     // A non-empty packet in the optional "TICK" input stream wakes up the
     // calculator.
+    // DEPRECATED as timestamp bound updates are processed by default in this
+    // calculator.
     if (cc->Inputs().HasTag("TICK")) {
       cc->Inputs().Tag("TICK").SetAny();
     }

mediapipe/calculators/core/clip_vector_size_calculator.cc

@@ -17,6 +17,7 @@
 #include <vector>
 
 #include "mediapipe/framework/calculator_framework.h"
+#include "mediapipe/framework/formats/detection.pb.h"
 #include "mediapipe/framework/formats/rect.pb.h"
 
 namespace mediapipe {
@@ -25,4 +26,8 @@ typedef ClipVectorSizeCalculator<::mediapipe::NormalizedRect>
     ClipNormalizedRectVectorSizeCalculator;
 REGISTER_CALCULATOR(ClipNormalizedRectVectorSizeCalculator);
 
+typedef ClipVectorSizeCalculator<::mediapipe::Detection>
+    ClipDetectionVectorSizeCalculator;
+REGISTER_CALCULATOR(ClipDetectionVectorSizeCalculator);
+
 }  // namespace mediapipe

mediapipe/calculators/core/end_loop_calculator.cc

@@ -16,6 +16,7 @@
 
 #include <vector>
 
+#include "mediapipe/framework/formats/classification.pb.h"
 #include "mediapipe/framework/formats/landmark.pb.h"
 #include "mediapipe/framework/formats/rect.pb.h"
 #include "mediapipe/util/render_data.pb.h"
@@ -37,4 +38,8 @@ typedef EndLoopCalculator<std::vector<::mediapipe::RenderData>>
     EndLoopRenderDataCalculator;
 REGISTER_CALCULATOR(EndLoopRenderDataCalculator);
 
+typedef EndLoopCalculator<std::vector<::mediapipe::ClassificationList>>
+    EndLoopClassificationListCalculator;
+REGISTER_CALCULATOR(EndLoopClassificationListCalculator);
+
 }  // namespace mediapipe

mediapipe/calculators/core/previous_loopback_calculator.cc

@@ -25,13 +25,17 @@ namespace mediapipe {
 // together with some previous output.
 //
 // For the first packet that arrives on the MAIN input, the timestamp bound is
-// advanced on the output. Downstream calculators will see this as an empty
+// advanced on the PREV_LOOP. Downstream calculators will see this as an empty
 // packet. This way they are not kept waiting for the previous output, which
 // for the first iteration does not exist.
 //
-// Thereafter, each packet received on MAIN is matched with a packet received
+// Thereafter,
-// on LOOP; the LOOP packet's timestamp is changed to that of the MAIN packet,
+// - Each non-empty MAIN packet results in:
-// and it is output on PREV_LOOP.
+//   a) a PREV_LOOP packet with contents of the LOOP packet received at the
+//      timestamp of the previous non-empty MAIN packet
+//   b) or in a PREV_LOOP timestamp bound update if the LOOP packet was empty.
+// - Each empty MAIN packet indicating timestamp bound update results in a
+//   PREV_LOOP timestamp bound update.
 //
 // Example config:
 // node {
@@ -56,83 +60,115 @@ class PreviousLoopbackCalculator : public CalculatorBase {
     // TODO: an optional PREV_TIMESTAMP output could be added to
     // carry the original timestamp of the packet on PREV_LOOP.
     cc->SetInputStreamHandler("ImmediateInputStreamHandler");
+    // Process() function is invoked in response to MAIN/LOOP stream timestamp
+    // bound updates.
+    cc->SetProcessTimestampBounds(true);
     return ::mediapipe::OkStatus();
   }
 
   ::mediapipe::Status Open(CalculatorContext* cc) final {
     main_id_ = cc->Inputs().GetId("MAIN", 0);
     loop_id_ = cc->Inputs().GetId("LOOP", 0);
-    loop_out_id_ = cc->Outputs().GetId("PREV_LOOP", 0);
+    prev_loop_id_ = cc->Outputs().GetId("PREV_LOOP", 0);
     cc->Outputs()
-        .Get(loop_out_id_)
+        .Get(prev_loop_id_)
         .SetHeader(cc->Inputs().Get(loop_id_).Header());
-
-    // Use an empty packet for the first round, since there is no previous
-    // output.
-    loopback_packets_.push_back({});
-
     return ::mediapipe::OkStatus();
   }
 
   ::mediapipe::Status Process(CalculatorContext* cc) final {
-    Packet& main_packet = cc->Inputs().Get(main_id_).Value();
+    // Non-empty packets and empty packets indicating timestamp bound updates
+    // are guaranteed to have timestamps greater than timestamps of previous
+    // packets within the same stream. Calculator tracks and operates on such
+    // packets.
+
+    const Packet& main_packet = cc->Inputs().Get(main_id_).Value();
+    if (prev_main_ts_ < main_packet.Timestamp()) {
+      Timestamp loop_timestamp;
       if (!main_packet.IsEmpty()) {
-      main_ts_.push_back(main_packet.Timestamp());
+        loop_timestamp = prev_non_empty_main_ts_;
-    }
+        prev_non_empty_main_ts_ = main_packet.Timestamp();
-    Packet& loopback_packet = cc->Inputs().Get(loop_id_).Value();
-    if (!loopback_packet.IsEmpty()) {
-      loopback_packets_.push_back(loopback_packet);
-      while (!main_ts_.empty() &&
-             main_ts_.front() <= loopback_packets_.front().Timestamp()) {
-        main_ts_.pop_front();
-      }
-    }
-    auto& loop_out = cc->Outputs().Get(loop_out_id_);
-
-    while (!main_ts_.empty() && !loopback_packets_.empty()) {
-      Timestamp main_timestamp = main_ts_.front();
-      main_ts_.pop_front();
-      Packet previous_loopback = loopback_packets_.front().At(main_timestamp);
-      loopback_packets_.pop_front();
-
-      if (previous_loopback.IsEmpty()) {
-        // TODO: SetCompleteTimestampBound would be more useful.
-        loop_out.SetNextTimestampBound(main_timestamp + 1);
       } else {
-        loop_out.AddPacket(std::move(previous_loopback));
+        // Calculator advances PREV_LOOP timestamp bound in response to empty
+        // MAIN packet, hence not caring about corresponding loop packet.
+        loop_timestamp = Timestamp::Unset();
+      }
+      main_packet_specs_.push_back({.timestamp = main_packet.Timestamp(),
+                                    .loop_timestamp = loop_timestamp});
+      prev_main_ts_ = main_packet.Timestamp();
+    }
+
+    const Packet& loop_packet = cc->Inputs().Get(loop_id_).Value();
+    if (prev_loop_ts_ < loop_packet.Timestamp()) {
+      loop_packets_.push_back(loop_packet);
+      prev_loop_ts_ = loop_packet.Timestamp();
+    }
+
+    auto& prev_loop = cc->Outputs().Get(prev_loop_id_);
+    while (!main_packet_specs_.empty() && !loop_packets_.empty()) {
+      // The earliest MAIN packet.
+      const MainPacketSpec& main_spec = main_packet_specs_.front();
+      // The earliest LOOP packet.
+      const Packet& loop_candidate = loop_packets_.front();
+      // Match LOOP and MAIN packets.
+      if (main_spec.loop_timestamp < loop_candidate.Timestamp()) {
+        // No LOOP packet can match the MAIN packet under review.
+        prev_loop.SetNextTimestampBound(main_spec.timestamp + 1);
+        main_packet_specs_.pop_front();
+      } else if (main_spec.loop_timestamp > loop_candidate.Timestamp()) {
+        // No MAIN packet can match the LOOP packet under review.
+        loop_packets_.pop_front();
+      } else {
+        // Exact match found.
+        if (loop_candidate.IsEmpty()) {
+          // However, LOOP packet is empty.
+          prev_loop.SetNextTimestampBound(main_spec.timestamp + 1);
+        } else {
+          prev_loop.AddPacket(loop_candidate.At(main_spec.timestamp));
+        }
+        loop_packets_.pop_front();
+        main_packet_specs_.pop_front();
       }
     }
 
-    // In case of an empty loopback input, the next timestamp bound for
+    if (main_packet_specs_.empty() && cc->Inputs().Get(main_id_).IsDone()) {
-    // loopback input is the loopback timestamp + 1.  The next timestamp bound
+      prev_loop.Close();
-    // for output is set and the main_ts_ vector is truncated accordingly.
-    if (loopback_packet.IsEmpty() &&
-        loopback_packet.Timestamp() != Timestamp::Unstarted()) {
-      Timestamp loopback_bound =
-          loopback_packet.Timestamp().NextAllowedInStream();
-      while (!main_ts_.empty() && main_ts_.front() <= loopback_bound) {
-        main_ts_.pop_front();
-      }
-      if (main_ts_.empty()) {
-        loop_out.SetNextTimestampBound(loopback_bound.NextAllowedInStream());
-      }
-    }
-    if (!main_ts_.empty()) {
-      loop_out.SetNextTimestampBound(main_ts_.front());
-    }
-    if (cc->Inputs().Get(main_id_).IsDone() && main_ts_.empty()) {
-      loop_out.Close();
     }
     return ::mediapipe::OkStatus();
   }
 
  private:
+  struct MainPacketSpec {
+    Timestamp timestamp;
+    // Expected timestamp of the packet from LOOP stream that corresponds to the
+    // packet from MAIN stream descirbed by this spec.
+    Timestamp loop_timestamp;
+  };
+
   CollectionItemId main_id_;
   CollectionItemId loop_id_;
-  CollectionItemId loop_out_id_;
+  CollectionItemId prev_loop_id_;
 
-  std::deque<Timestamp> main_ts_;
+  // Contains specs for MAIN packets which only can be:
-  std::deque<Packet> loopback_packets_;
+  // - non-empty packets
+  // - empty packets indicating timestamp bound updates
+  //
+  // Sorted according to packet timestamps.
+  std::deque<MainPacketSpec> main_packet_specs_;
+  Timestamp prev_main_ts_ = Timestamp::Unstarted();
+  Timestamp prev_non_empty_main_ts_ = Timestamp::Unstarted();
+
+  // Contains LOOP packets which only can be:
+  // - the very first empty packet
+  // - non empty packets
+  // - empty packets indicating timestamp bound updates
+  //
+  // Sorted according to packet timestamps.
+  std::deque<Packet> loop_packets_;
+  // Using "Timestamp::Unset" instead of "Timestamp::Unstarted" in order to
+  // allow addition of the very first empty packet (which doesn't indicate
+  // timestamp bound change necessarily).
+  Timestamp prev_loop_ts_ = Timestamp::Unset();
 };
 REGISTER_CALCULATOR(PreviousLoopbackCalculator);
 

mediapipe/calculators/core/previous_loopback_calculator_test.cc

@@ -13,6 +13,7 @@
 // limitations under the License.
 
 #include <algorithm>
+#include <functional>
 #include <memory>
 #include <string>
 #include <vector>
@@ -25,12 +26,17 @@
 #include "mediapipe/framework/port/gtest.h"
 #include "mediapipe/framework/port/integral_types.h"
 #include "mediapipe/framework/port/parse_text_proto.h"
+#include "mediapipe/framework/port/status.h"
 #include "mediapipe/framework/port/status_matchers.h"
 #include "mediapipe/framework/timestamp.h"
 #include "mediapipe/framework/tool/sink.h"
 
 namespace mediapipe {
 
+using ::testing::ElementsAre;
+using ::testing::Eq;
+using ::testing::Pair;
+using ::testing::Value;
 namespace {
 
 // Returns the timestamp values for a vector of Packets.
@@ -43,6 +49,23 @@ std::vector<int64> TimestampValues(const std::vector<Packet>& packets) {
   return result;
 }
 
+MATCHER(EmptyPacket, negation ? "isn't empty" : "is empty") {
+  if (arg.IsEmpty()) {
+    return true;
+  }
+  return false;
+}
+
+MATCHER_P(IntPacket, value, "") {
+  return Value(arg.template Get<int>(), Eq(value));
+}
+
+MATCHER_P2(PairPacket, timestamp, pair, "") {
+  Timestamp actual_timestamp = arg.Timestamp();
+  const auto& actual_pair = arg.template Get<std::pair<Packet, Packet>>();
+  return Value(actual_timestamp, Eq(timestamp)) && Value(actual_pair, pair);
+}
+
 TEST(PreviousLoopbackCalculator, CorrectTimestamps) {
   std::vector<Packet> in_prev;
   CalculatorGraphConfig graph_config_ =
@@ -81,32 +104,30 @@ TEST(PreviousLoopbackCalculator, CorrectTimestamps) {
     MP_EXPECT_OK(graph_.AddPacketToInputStream(
         input_name, MakePacket<int>(n).At(Timestamp(n))));
   };
-  auto pair_values = [](const Packet& packet) {
-    auto pair = packet.Get<std::pair<Packet, Packet>>();
-    int first = pair.first.IsEmpty() ? -1 : pair.first.Get<int>();
-    int second = pair.second.IsEmpty() ? -1 : pair.second.Get<int>();
-    return std::make_pair(first, second);
-  };
 
   send_packet("in", 1);
   MP_EXPECT_OK(graph_.WaitUntilIdle());
-  EXPECT_EQ(TimestampValues(in_prev), (std::vector<int64>{1}));
+  EXPECT_THAT(TimestampValues(in_prev), ElementsAre(1));
-  EXPECT_EQ(pair_values(in_prev.back()), std::make_pair(1, -1));
+  EXPECT_THAT(in_prev.back(),
+              PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())));
 
   send_packet("in", 2);
   MP_EXPECT_OK(graph_.WaitUntilIdle());
-  EXPECT_EQ(TimestampValues(in_prev), (std::vector<int64>{1, 2}));
+  EXPECT_THAT(TimestampValues(in_prev), ElementsAre(1, 2));
-  EXPECT_EQ(pair_values(in_prev.back()), std::make_pair(2, 1));
+  EXPECT_THAT(in_prev.back(),
+              PairPacket(Timestamp(2), Pair(IntPacket(2), IntPacket(1))));
 
   send_packet("in", 5);
   MP_EXPECT_OK(graph_.WaitUntilIdle());
-  EXPECT_EQ(TimestampValues(in_prev), (std::vector<int64>{1, 2, 5}));
+  EXPECT_THAT(TimestampValues(in_prev), ElementsAre(1, 2, 5));
-  EXPECT_EQ(pair_values(in_prev.back()), std::make_pair(5, 2));
+  EXPECT_THAT(in_prev.back(),
+              PairPacket(Timestamp(5), Pair(IntPacket(5), IntPacket(2))));
 
   send_packet("in", 15);
   MP_EXPECT_OK(graph_.WaitUntilIdle());
-  EXPECT_EQ(TimestampValues(in_prev), (std::vector<int64>{1, 2, 5, 15}));
+  EXPECT_THAT(TimestampValues(in_prev), ElementsAre(1, 2, 5, 15));
-  EXPECT_EQ(pair_values(in_prev.back()), std::make_pair(15, 5));
+  EXPECT_THAT(in_prev.back(),
+              PairPacket(Timestamp(15), Pair(IntPacket(15), IntPacket(5))));
 
   MP_EXPECT_OK(graph_.CloseAllInputStreams());
   MP_EXPECT_OK(graph_.WaitUntilDone());
@@ -185,24 +206,24 @@ TEST(PreviousLoopbackCalculator, ClosesCorrectly) {
 
   send_packet("in", 1);
   MP_EXPECT_OK(graph_.WaitUntilIdle());
-  EXPECT_EQ(TimestampValues(outputs), (std::vector<int64>{1}));
+  EXPECT_THAT(TimestampValues(outputs), ElementsAre(1));
 
   send_packet("in", 2);
   MP_EXPECT_OK(graph_.WaitUntilIdle());
-  EXPECT_EQ(TimestampValues(outputs), (std::vector<int64>{1, 2}));
+  EXPECT_THAT(TimestampValues(outputs), ElementsAre(1, 2));
 
   send_packet("in", 5);
   MP_EXPECT_OK(graph_.WaitUntilIdle());
-  EXPECT_EQ(TimestampValues(outputs), (std::vector<int64>{1, 2, 5}));
+  EXPECT_THAT(TimestampValues(outputs), ElementsAre(1, 2, 5));
 
   send_packet("in", 15);
   MP_EXPECT_OK(graph_.WaitUntilIdle());
-  EXPECT_EQ(TimestampValues(outputs), (std::vector<int64>{1, 2, 5, 15}));
+  EXPECT_THAT(TimestampValues(outputs), ElementsAre(1, 2, 5, 15));
 
   MP_EXPECT_OK(graph_.CloseAllInputStreams());
   MP_EXPECT_OK(graph_.WaitUntilIdle());
-  EXPECT_EQ(TimestampValues(outputs),
+  EXPECT_THAT(TimestampValues(outputs),
-            (std::vector<int64>{1, 2, 5, 15, Timestamp::Max().Value()}));
+              ElementsAre(1, 2, 5, 15, Timestamp::Max().Value()));
 
   MP_EXPECT_OK(graph_.WaitUntilDone());
 }
@@ -247,16 +268,12 @@ TEST(PreviousLoopbackCalculator, EmptyLoopForever) {
         input_name, MakePacket<int>(n).At(Timestamp(n))));
   };
 
-  send_packet("in", 0);
+  for (int main_ts = 0; main_ts < 50; ++main_ts) {
-  MP_EXPECT_OK(graph_.WaitUntilIdle());
-  EXPECT_EQ(TimestampValues(outputs), (std::vector<int64>{0}));
-
-  for (int main_ts = 1; main_ts < 50; ++main_ts) {
     send_packet("in", main_ts);
     MP_EXPECT_OK(graph_.WaitUntilIdle());
     std::vector<int64> ts_values = TimestampValues(outputs);
     EXPECT_EQ(ts_values.size(), main_ts + 1);
-    for (int j = 0; j < main_ts; ++j) {
+    for (int j = 0; j < main_ts + 1; ++j) {
       EXPECT_EQ(ts_values[j], j);
     }
   }
@@ -266,5 +283,487 @@ TEST(PreviousLoopbackCalculator, EmptyLoopForever) {
   MP_EXPECT_OK(graph_.WaitUntilDone());
 }
 
+class PreviousLoopbackCalculatorProcessingTimestampsTest
+    : public testing::Test {
+ protected:
+  void SetUp() override {
+    CalculatorGraphConfig graph_config =
+        ParseTextProtoOrDie<CalculatorGraphConfig>(R"(
+          input_stream: 'input'
+          input_stream: 'force_main_empty'
+          input_stream: 'force_loop_empty'
+          # Used to indicate "main" timestamp bound updates.
+          node {
+            calculator: 'GateCalculator'
+            input_stream: 'input'
+            input_stream: 'DISALLOW:force_main_empty'
+            output_stream: 'main'
+          }
+          node {
+            calculator: 'PreviousLoopbackCalculator'
+            input_stream: 'MAIN:main'
+            input_stream: 'LOOP:loop'
+            input_stream_info: { tag_index: 'LOOP' back_edge: true }
+            output_stream: 'PREV_LOOP:prev_loop'
+          }
+          node {
+            calculator: 'PassThroughCalculator'
+            input_stream: 'input'
+            input_stream: 'prev_loop'
+            output_stream: 'passed_through_input'
+            output_stream: 'passed_through_prev_loop'
+          }
+          # Used to indicate "loop" timestamp bound updates.
+          node {
+            calculator: 'GateCalculator'
+            input_stream: 'input'
+            input_stream: 'DISALLOW:force_loop_empty'
+            output_stream: 'loop'
+          }
+          node {
+            calculator: 'MakePairCalculator'
+            input_stream: 'passed_through_input'
+            input_stream: 'passed_through_prev_loop'
+            output_stream: 'passed_through_input_and_prev_loop'
+          }
+        )");
+    tool::AddVectorSink("passed_through_input_and_prev_loop", &graph_config,
+                        &output_packets_);
+    MP_ASSERT_OK(graph_.Initialize(graph_config, {}));
+    MP_ASSERT_OK(graph_.StartRun({}));
+  }
+
+  void SendPackets(int timestamp, int input, bool force_main_empty,
+                   bool force_loop_empty) {
+    MP_ASSERT_OK(graph_.AddPacketToInputStream(
+        "input", MakePacket<int>(input).At(Timestamp(timestamp))));
+    MP_ASSERT_OK(graph_.AddPacketToInputStream(
+        "force_main_empty",
+        MakePacket<bool>(force_main_empty).At(Timestamp(timestamp))));
+    MP_ASSERT_OK(graph_.AddPacketToInputStream(
+        "force_loop_empty",
+        MakePacket<bool>(force_loop_empty).At(Timestamp(timestamp))));
+  }
+
+  CalculatorGraph graph_;
+  std::vector<Packet> output_packets_;
+};
+
+TEST_F(PreviousLoopbackCalculatorProcessingTimestampsTest,
+       MultiplePacketsEmptyMainNonEmptyLoop) {
+  SendPackets(/*timestamp=*/1, /*input=*/1, /*force_main_empty=*/true,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/2, /*input=*/2, /*force_main_empty=*/true,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/3, /*input=*/3, /*force_main_empty=*/true,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket())),
+                  PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/5, /*input=*/5, /*force_main_empty=*/true,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket())),
+                  PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket())),
+                  PairPacket(Timestamp(5), Pair(IntPacket(5), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/15, /*input=*/15,
+              /*force_main_empty=*/true,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(
+          PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+          PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket())),
+          PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket())),
+          PairPacket(Timestamp(5), Pair(IntPacket(5), EmptyPacket())),
+          PairPacket(Timestamp(15), Pair(IntPacket(15), EmptyPacket()))));
+
+  MP_EXPECT_OK(graph_.CloseAllInputStreams());
+  MP_EXPECT_OK(graph_.WaitUntilDone());
+}
+
+TEST_F(PreviousLoopbackCalculatorProcessingTimestampsTest,
+       MultiplePacketsNonEmptyMainEmptyLoop) {
+  SendPackets(/*timestamp=*/1, /*input=*/1,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/2, /*input=*/2,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/3, /*input=*/3,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket())),
+                  PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/5, /*input=*/5,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket())),
+                  PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket())),
+                  PairPacket(Timestamp(5), Pair(IntPacket(5), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/15, /*input=*/15,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(
+          PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+          PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket())),
+          PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket())),
+          PairPacket(Timestamp(5), Pair(IntPacket(5), EmptyPacket())),
+          PairPacket(Timestamp(15), Pair(IntPacket(15), EmptyPacket()))));
+
+  MP_EXPECT_OK(graph_.CloseAllInputStreams());
+  MP_EXPECT_OK(graph_.WaitUntilDone());
+}
+
+TEST_F(PreviousLoopbackCalculatorProcessingTimestampsTest,
+       MultiplePacketsAlteringMainNonEmptyLoop) {
+  SendPackets(/*timestamp=*/1, /*input=*/1,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/2, /*input=*/2, /*force_main_empty=*/true,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/3, /*input=*/3,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket())),
+                  PairPacket(Timestamp(3), Pair(IntPacket(3), IntPacket(1)))));
+
+  SendPackets(/*timestamp=*/5, /*input=*/5,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket())),
+                  PairPacket(Timestamp(3), Pair(IntPacket(3), IntPacket(1))),
+                  PairPacket(Timestamp(5), Pair(IntPacket(5), IntPacket(3)))));
+
+  SendPackets(/*timestamp=*/15, /*input=*/15,
+              /*force_main_empty=*/true,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(
+          PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+          PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket())),
+          PairPacket(Timestamp(3), Pair(IntPacket(3), IntPacket(1))),
+          PairPacket(Timestamp(5), Pair(IntPacket(5), IntPacket(3))),
+          PairPacket(Timestamp(15), Pair(IntPacket(15), EmptyPacket()))));
+
+  MP_EXPECT_OK(graph_.CloseAllInputStreams());
+  MP_EXPECT_OK(graph_.WaitUntilDone());
+}
+
+TEST_F(PreviousLoopbackCalculatorProcessingTimestampsTest,
+       MultiplePacketsNonEmptyMainAlteringLoop) {
+  SendPackets(/*timestamp=*/1, /*input=*/1,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/2, /*input=*/2,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), IntPacket(1)))));
+
+  SendPackets(/*timestamp=*/3, /*input=*/3,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), IntPacket(1))),
+                  PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/5, /*input=*/5,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), IntPacket(1))),
+                  PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket())),
+                  PairPacket(Timestamp(5), Pair(IntPacket(5), IntPacket(3)))));
+
+  SendPackets(/*timestamp=*/15, /*input=*/15,
+              /*force_main_empty=*/false,
+              /*force_loop_empty=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(
+          PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+          PairPacket(Timestamp(2), Pair(IntPacket(2), IntPacket(1))),
+          PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket())),
+          PairPacket(Timestamp(5), Pair(IntPacket(5), IntPacket(3))),
+          PairPacket(Timestamp(15), Pair(IntPacket(15), EmptyPacket()))));
+
+  MP_EXPECT_OK(graph_.CloseAllInputStreams());
+  MP_EXPECT_OK(graph_.WaitUntilDone());
+}
+
+TEST_F(PreviousLoopbackCalculatorProcessingTimestampsTest,
+       MultiplePacketsCheckIfLastCorrectAlteringMainAlteringLoop) {
+  int num_packets = 1000;
+  for (int i = 0; i < num_packets; ++i) {
+    bool force_main_empty = i % 3 == 0 ? true : false;
+    bool force_loop_empty = i % 2 == 0 ? true : false;
+    SendPackets(/*timestamp=*/i + 1, /*input=*/i + 1, force_main_empty,
+                force_loop_empty);
+  }
+  SendPackets(/*timestamp=*/num_packets + 1,
+              /*input=*/num_packets + 1, /*force_main_empty=*/false,
+              /*force_loop_empty=*/false);
+  SendPackets(/*timestamp=*/num_packets + 2,
+              /*input=*/num_packets + 2, /*force_main_empty=*/false,
+              /*force_loop_empty=*/false);
+
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  ASSERT_FALSE(output_packets_.empty());
+  EXPECT_THAT(
+      output_packets_.back(),
+      PairPacket(Timestamp(num_packets + 2),
+                 Pair(IntPacket(num_packets + 2), IntPacket(num_packets + 1))));
+
+  MP_EXPECT_OK(graph_.CloseAllInputStreams());
+  MP_EXPECT_OK(graph_.WaitUntilDone());
+}
+
+// Similar to GateCalculator, but it doesn't propagate timestamp bound updates.
+class DroppingGateCalculator : public CalculatorBase {
+ public:
+  static ::mediapipe::Status GetContract(CalculatorContract* cc) {
+    cc->Inputs().Index(0).SetAny();
+    cc->Inputs().Tag("DISALLOW").Set<bool>();
+    cc->Outputs().Index(0).SetSameAs(&cc->Inputs().Index(0));
+    return ::mediapipe::OkStatus();
+  }
+
+  ::mediapipe::Status Process(CalculatorContext* cc) final {
+    if (!cc->Inputs().Index(0).IsEmpty() &&
+        !cc->Inputs().Tag("DISALLOW").Get<bool>()) {
+      cc->Outputs().Index(0).AddPacket(cc->Inputs().Index(0).Value());
+    }
+    return ::mediapipe::OkStatus();
+  }
+};
+REGISTER_CALCULATOR(DroppingGateCalculator);
+
+// Tests PreviousLoopbackCalculator in cases when there are no "LOOP" timestamp
+// bound updates and non-empty packets for a while and the aforementioned start
+// to arrive at some point. So, "PREV_LOOP" is delayed for a couple of inputs.
+class PreviousLoopbackCalculatorDelayBehaviorTest : public testing::Test {
+ protected:
+  void SetUp() override {
+    CalculatorGraphConfig graph_config =
+        ParseTextProtoOrDie<CalculatorGraphConfig>(R"(
+          input_stream: 'input'
+          # Drops "loop" when set to "true", delaying output of prev_loop, hence
+          # delaying output of the graph.
+          input_stream: 'delay_next_output'
+          node {
+            calculator: 'PreviousLoopbackCalculator'
+            input_stream: 'MAIN:input'
+            input_stream: 'LOOP:loop'
+            input_stream_info: { tag_index: 'LOOP' back_edge: true }
+            output_stream: 'PREV_LOOP:prev_loop'
+          }
+          node {
+            calculator: 'PassThroughCalculator'
+            input_stream: 'input'
+            input_stream: 'prev_loop'
+            output_stream: 'passed_through_input'
+            output_stream: 'passed_through_prev_loop'
+          }
+          node {
+            calculator: 'DroppingGateCalculator'
+            input_stream: 'input'
+            input_stream: 'DISALLOW:delay_next_output'
+            output_stream: 'loop'
+          }
+          node {
+            calculator: 'MakePairCalculator'
+            input_stream: 'passed_through_input'
+            input_stream: 'passed_through_prev_loop'
+            output_stream: 'passed_through_input_and_prev_loop'
+          }
+        )");
+    tool::AddVectorSink("passed_through_input_and_prev_loop", &graph_config,
+                        &output_packets_);
+    MP_ASSERT_OK(graph_.Initialize(graph_config, {}));
+    MP_ASSERT_OK(graph_.StartRun({}));
+  }
+
+  void SendPackets(int timestamp, int input, bool delay_next_output) {
+    MP_ASSERT_OK(graph_.AddPacketToInputStream(
+        "input", MakePacket<int>(input).At(Timestamp(timestamp))));
+    MP_ASSERT_OK(graph_.AddPacketToInputStream(
+        "delay_next_output",
+        MakePacket<bool>(delay_next_output).At(Timestamp(timestamp))));
+  }
+
+  CalculatorGraph graph_;
+  std::vector<Packet> output_packets_;
+};
+
+TEST_F(PreviousLoopbackCalculatorDelayBehaviorTest, MultipleDelayedOutputs) {
+  SendPackets(/*timestamp=*/1, /*input=*/1, /*delay_next_output=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/2, /*input=*/2, /*delay_next_output=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/3, /*input=*/3, /*delay_next_output=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/5, /*input=*/5, /*delay_next_output=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket())),
+                  PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket())),
+                  PairPacket(Timestamp(5), Pair(IntPacket(5), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/15, /*input=*/15, /*delay_next_output=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(
+          PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+          PairPacket(Timestamp(2), Pair(IntPacket(2), EmptyPacket())),
+          PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket())),
+          PairPacket(Timestamp(5), Pair(IntPacket(5), EmptyPacket())),
+          PairPacket(Timestamp(15), Pair(IntPacket(15), IntPacket(5)))));
+
+  MP_EXPECT_OK(graph_.CloseAllInputStreams());
+  MP_EXPECT_OK(graph_.WaitUntilDone());
+}
+
+TEST_F(PreviousLoopbackCalculatorDelayBehaviorTest,
+       NonDelayedOutputFollowedByMultipleDelayedOutputs) {
+  SendPackets(/*timestamp=*/1, /*input=*/1, /*delay_next_output=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/2, /*input=*/2, /*delay_next_output=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), IntPacket(1)))));
+
+  SendPackets(/*timestamp=*/3, /*input=*/3, /*delay_next_output=*/true);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), IntPacket(1)))));
+
+  SendPackets(/*timestamp=*/5, /*input=*/5, /*delay_next_output=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+                  PairPacket(Timestamp(2), Pair(IntPacket(2), IntPacket(1))),
+                  PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket())),
+                  PairPacket(Timestamp(5), Pair(IntPacket(5), EmptyPacket()))));
+
+  SendPackets(/*timestamp=*/15, /*input=*/15, /*delay_next_output=*/false);
+  MP_EXPECT_OK(graph_.WaitUntilIdle());
+  EXPECT_THAT(
+      output_packets_,
+      ElementsAre(
+          PairPacket(Timestamp(1), Pair(IntPacket(1), EmptyPacket())),
+          PairPacket(Timestamp(2), Pair(IntPacket(2), IntPacket(1))),
+          PairPacket(Timestamp(3), Pair(IntPacket(3), EmptyPacket())),
+          PairPacket(Timestamp(5), Pair(IntPacket(5), EmptyPacket())),
+          PairPacket(Timestamp(15), Pair(IntPacket(15), IntPacket(5)))));
+
+  MP_EXPECT_OK(graph_.CloseAllInputStreams());
+  MP_EXPECT_OK(graph_.WaitUntilDone());
+}
+
 }  // anonymous namespace
 }  // namespace mediapipe

mediapipe/calculators/core/split_vector_calculator.cc

@@ -16,6 +16,7 @@
 
 #include <vector>
 
+#include "mediapipe/framework/formats/detection.pb.h"
 #include "mediapipe/framework/formats/landmark.pb.h"
 #include "mediapipe/framework/formats/rect.pb.h"
 #include "tensorflow/lite/interpreter.h"
@@ -48,6 +49,10 @@ typedef SplitVectorCalculator<::mediapipe::NormalizedLandmark, false>
     SplitLandmarkVectorCalculator;
 REGISTER_CALCULATOR(SplitLandmarkVectorCalculator);
 
+typedef SplitVectorCalculator<::mediapipe::NormalizedLandmarkList, false>
+    SplitNormalizedLandmarkListVectorCalculator;
+REGISTER_CALCULATOR(SplitNormalizedLandmarkListVectorCalculator);
+
 typedef SplitVectorCalculator<::mediapipe::NormalizedRect, false>
     SplitNormalizedRectVectorCalculator;
 REGISTER_CALCULATOR(SplitNormalizedRectVectorCalculator);
@@ -57,4 +62,9 @@ typedef SplitVectorCalculator<::tflite::gpu::gl::GlBuffer, true>
     MovableSplitGlBufferVectorCalculator;
 REGISTER_CALCULATOR(MovableSplitGlBufferVectorCalculator);
 #endif
+
+typedef SplitVectorCalculator<::mediapipe::Detection, false>
+    SplitDetectionVectorCalculator;
+REGISTER_CALCULATOR(SplitDetectionVectorCalculator);
+
 }  // namespace mediapipe

mediapipe/calculators/image/BUILD

@@ -422,9 +422,12 @@ cc_library(
         ":recolor_calculator_cc_proto",
         "//mediapipe/framework:calculator_framework",
         "//mediapipe/framework/formats:image_frame",
+        "//mediapipe/framework/formats:image_frame_opencv",
         "//mediapipe/framework/port:status",
         "//mediapipe/framework/port:ret_check",
         "//mediapipe/util:color_cc_proto",
+        "//mediapipe/framework/port:opencv_core",
+        "//mediapipe/framework/port:opencv_imgproc",
     ] + select({
         "//mediapipe/gpu:disable_gpu": [],
         "//conditions:default": [

mediapipe/calculators/image/recolor_calculator.cc

@@ -17,6 +17,9 @@
 #include "mediapipe/calculators/image/recolor_calculator.pb.h"
 #include "mediapipe/framework/calculator_framework.h"
 #include "mediapipe/framework/formats/image_frame.h"
+#include "mediapipe/framework/formats/image_frame_opencv.h"
+#include "mediapipe/framework/port/opencv_core_inc.h"
+#include "mediapipe/framework/port/opencv_imgproc_inc.h"
 #include "mediapipe/framework/port/ret_check.h"
 #include "mediapipe/framework/port/status.h"
 #include "mediapipe/util/color.pb.h"
@@ -39,8 +42,6 @@ namespace mediapipe {
 // The luminance of the input image is used to adjust the blending weight,
 // to help preserve image textures.
 //
-// TODO implement cpu support.
-//
 // Inputs:
 //   One of the following IMAGE tags:
 //   IMAGE: An ImageFrame input image, RGB or RGBA.
@@ -71,6 +72,8 @@ namespace mediapipe {
 //    }
 //  }
 //
+// Note: Cannot mix-match CPU & GPU inputs/outputs.
+//       CPU-in & CPU-out <or> GPU-in & GPU-out
 class RecolorCalculator : public CalculatorBase {
  public:
   RecolorCalculator() = default;
@@ -138,6 +141,11 @@ REGISTER_CALCULATOR(RecolorCalculator);
     cc->Outputs().Tag("IMAGE").Set<ImageFrame>();
   }
 
+  // Confirm only one of the input streams is present.
+  RET_CHECK(cc->Inputs().HasTag("IMAGE") ^ cc->Inputs().HasTag("IMAGE_GPU"));
+  // Confirm only one of the output streams is present.
+  RET_CHECK(cc->Outputs().HasTag("IMAGE") ^ cc->Outputs().HasTag("IMAGE_GPU"));
+
   if (use_gpu) {
 #if !defined(MEDIAPIPE_DISABLE_GPU)
     MP_RETURN_IF_ERROR(mediapipe::GlCalculatorHelper::UpdateContract(cc));
@@ -193,7 +201,62 @@ REGISTER_CALCULATOR(RecolorCalculator);
 }
 
 ::mediapipe::Status RecolorCalculator::RenderCpu(CalculatorContext* cc) {
-  return ::mediapipe::UnimplementedError("CPU support is not implemented yet.");
+  if (cc->Inputs().Tag("MASK").IsEmpty()) {
+    return ::mediapipe::OkStatus();
+  }
+  // Get inputs and setup output.
+  const auto& input_img = cc->Inputs().Tag("IMAGE").Get<ImageFrame>();
+  const auto& mask_img = cc->Inputs().Tag("MASK").Get<ImageFrame>();
+
+  cv::Mat input_mat = formats::MatView(&input_img);
+  cv::Mat mask_mat = formats::MatView(&mask_img);
+
+  RET_CHECK(input_mat.channels() == 3);  // RGB only.
+
+  if (mask_mat.channels() > 1) {
+    std::vector<cv::Mat> channels;
+    cv::split(mask_mat, channels);
+    if (mask_channel_ == mediapipe::RecolorCalculatorOptions_MaskChannel_ALPHA)
+      mask_mat = channels[3];
+    else
+      mask_mat = channels[0];
+  }
+  cv::Mat mask_full;
+  cv::resize(mask_mat, mask_full, input_mat.size());
+
+  auto output_img = absl::make_unique<ImageFrame>(
+      input_img.Format(), input_mat.cols, input_mat.rows);
+  cv::Mat output_mat = mediapipe::formats::MatView(output_img.get());
+
+  // From GPU shader:
+  /*
+      vec4 weight = texture2D(mask, sample_coordinate);
+      vec4 color1 = texture2D(frame, sample_coordinate);
+      vec4 color2 = vec4(recolor, 1.0);
+
+      float luminance = dot(color1.rgb, vec3(0.299, 0.587, 0.114));
+      float mix_value = weight.MASK_COMPONENT * luminance;
+
+      fragColor = mix(color1, color2, mix_value);
+  */
+  for (int i = 0; i < output_mat.rows; ++i) {
+    for (int j = 0; j < output_mat.cols; ++j) {
+      float weight = mask_full.at<uchar>(i, j) * (1.0 / 255.0);
+      cv::Vec3f color1 = input_mat.at<cv::Vec3b>(i, j);
+      cv::Vec3f color2 = {color_[0], color_[1], color_[2]};
+
+      float luminance =
+          (color1[0] * 0.299 + color1[1] * 0.587 + color1[2] * 0.114) / 255;
+      float mix_value = weight * luminance;
+
+      cv::Vec3b mix_color = color1 * (1.0 - mix_value) + color2 * mix_value;
+      output_mat.at<cv::Vec3b>(i, j) = mix_color;
+    }
+  }
+
+  cc->Outputs().Tag("IMAGE").Add(output_img.release(), cc->InputTimestamp());
+
+  return ::mediapipe::OkStatus();
 }
 
 ::mediapipe::Status RecolorCalculator::RenderGpu(CalculatorContext* cc) {
@@ -303,9 +366,9 @@ void RecolorCalculator::GlRender() {
 
   if (!options.has_color()) RET_CHECK_FAIL() << "Missing color option.";
 
-  color_.push_back(options.color().r() / 255.0);
+  color_.push_back(options.color().r());
-  color_.push_back(options.color().g() / 255.0);
+  color_.push_back(options.color().g());
-  color_.push_back(options.color().b() / 255.0);
+  color_.push_back(options.color().b());
 
   return ::mediapipe::OkStatus();
 }
@@ -378,8 +441,8 @@ void RecolorCalculator::GlRender() {
   glUseProgram(program_);
   glUniform1i(glGetUniformLocation(program_, "frame"), 1);
   glUniform1i(glGetUniformLocation(program_, "mask"), 2);
-  glUniform3f(glGetUniformLocation(program_, "recolor"), color_[0], color_[1],
+  glUniform3f(glGetUniformLocation(program_, "recolor"), color_[0] / 255.0,
-              color_[2]);
+              color_[1] / 255.0, color_[2] / 255.0);
 #endif  //  !MEDIAPIPE_DISABLE_GPU
 
   return ::mediapipe::OkStatus();

mediapipe/calculators/tensorflow/BUILD

@@ -1110,6 +1110,7 @@ cc_test(
         ],
         "//mediapipe:android": [
             "@org_tensorflow//tensorflow/core:android_tensorflow_lib_with_ops_lite_proto_no_rtti_lib",
+            "@org_tensorflow//tensorflow/core:android_tensorflow_test_lib",
         ],
         "//mediapipe:ios": [
             "@org_tensorflow//tensorflow/core:ios_tensorflow_test_lib",

mediapipe/calculators/tflite/BUILD

@@ -222,9 +222,11 @@ cc_library(
     deps = [
         ":util",
         ":tflite_inference_calculator_cc_proto",
+        "@com_google_absl//absl/memory",
         "//mediapipe/framework:calculator_framework",
         "//mediapipe/util:resource_util",
         "@org_tensorflow//tensorflow/lite:framework",
+        "@org_tensorflow//tensorflow/lite/delegates/xnnpack:xnnpack_delegate",
         "@org_tensorflow//tensorflow/lite/kernels:builtin_ops",
         "//mediapipe/framework/stream_handler:fixed_size_input_stream_handler",
         "//mediapipe/framework/port:ret_check",
@@ -254,6 +256,10 @@ cc_library(
         "//mediapipe:android": [
             "@org_tensorflow//tensorflow/lite/delegates/nnapi:nnapi_delegate",
         ],
+    }) + select({
+        "//conditions:default": [
+            "//mediapipe/util:cpu_util",
+        ],
     }),
     alwayslink = 1,
 )
@@ -308,6 +314,20 @@ cc_library(
     alwayslink = 1,
 )
 
+cc_library(
+    name = "tflite_model_calculator",
+    srcs = ["tflite_model_calculator.cc"],
+    visibility = ["//visibility:public"],
+    deps = [
+        ":util",
+        "//mediapipe/framework:calculator_framework",
+        "//mediapipe/framework:packet",
+        "//mediapipe/framework/port:ret_check",
+        "@org_tensorflow//tensorflow/lite:framework",
+    ],
+    alwayslink = 1,
+)
+
 cc_library(
     name = "tflite_tensors_to_segmentation_calculator",
     srcs = ["tflite_tensors_to_segmentation_calculator.cc"],
@@ -478,6 +498,9 @@ cc_test(
     deps = [
         ":tflite_inference_calculator",
         ":tflite_inference_calculator_cc_proto",
+        ":tflite_model_calculator",
+        "//mediapipe/calculators/core:constant_side_packet_calculator",
+        "//mediapipe/calculators/util:local_file_contents_calculator",
         "//mediapipe/framework:calculator_framework",
         "//mediapipe/framework:calculator_runner",
         "//mediapipe/framework/deps:file_path",
@@ -485,7 +508,9 @@ cc_test(
         "//mediapipe/framework/port:integral_types",
         "//mediapipe/framework/port:parse_text_proto",
         "//mediapipe/framework/tool:validate_type",
+        "@com_google_absl//absl/memory",
         "@com_google_absl//absl/strings",
+        "@com_google_absl//absl/types:optional",
         "@org_tensorflow//tensorflow/lite:framework",
         "@org_tensorflow//tensorflow/lite/kernels:builtin_ops",
     ],
@@ -511,3 +536,19 @@ cc_test(
         "@org_tensorflow//tensorflow/lite/kernels:builtin_ops",
     ],
 )
+
+cc_test(
+    name = "tflite_model_calculator_test",
+    srcs = ["tflite_model_calculator_test.cc"],
+    data = ["testdata/add.bin"],
+    deps = [
+        ":tflite_model_calculator",
+        "//mediapipe/calculators/core:constant_side_packet_calculator",
+        "//mediapipe/calculators/util:local_file_contents_calculator",
+        "//mediapipe/framework:calculator_framework",
+        "//mediapipe/framework:calculator_runner",
+        "//mediapipe/framework/port:gtest_main",
+        "//mediapipe/framework/port:parse_text_proto",
+        "@org_tensorflow//tensorflow/lite:framework",
+    ],
+)

mediapipe/calculators/tflite/tflite_inference_calculator.cc

@@ -17,10 +17,16 @@
 #include <string>
 #include <vector>
 
+#include "absl/memory/memory.h"
 #include "mediapipe/calculators/tflite/tflite_inference_calculator.pb.h"
 #include "mediapipe/calculators/tflite/util.h"
 #include "mediapipe/framework/calculator_framework.h"
 #include "mediapipe/framework/port/ret_check.h"
+
+#if !defined(__EMSCRIPTEN__)
+#include "mediapipe/util/cpu_util.h"
+#endif  // !__EMSCRIPTEN__
+
 #include "mediapipe/util/resource_util.h"
 #include "tensorflow/lite/error_reporter.h"
 #include "tensorflow/lite/interpreter.h"
@@ -50,7 +56,7 @@
 #include "tensorflow/lite/delegates/gpu/metal_delegate.h"
 #include "tensorflow/lite/delegates/gpu/metal_delegate_internal.h"
 #endif  // iOS
-
+#include "tensorflow/lite/delegates/xnnpack/xnnpack_delegate.h"
 #if defined(MEDIAPIPE_ANDROID)
 #include "tensorflow/lite/delegates/nnapi/nnapi_delegate.h"
 #endif  // ANDROID
@@ -113,6 +119,23 @@ struct GPUData {
 };
 #endif
 
+// Returns number of threads to configure XNNPACK delegate with.
+// (Equal to user provided value if specified.  Otherwise, it returns number of
+// high cores (hard-coded to 1 for __EMSCRIPTEN__))
+int GetXnnpackNumThreads(
+    const mediapipe::TfLiteInferenceCalculatorOptions& opts) {
+  static constexpr int kDefaultNumThreads = -1;
+  if (opts.has_delegate() && opts.delegate().has_xnnpack() &&
+      opts.delegate().xnnpack().num_threads() != kDefaultNumThreads) {
+    return opts.delegate().xnnpack().num_threads();
+  }
+#if !defined(__EMSCRIPTEN__)
+  return InferHigherCoreIds().size();
+#else
+  return 1;
+#endif  // !__EMSCRIPTEN__
+}
+
 // Calculator Header Section
 
 // Runs inference on the provided input TFLite tensors and TFLite model.
@@ -139,6 +162,9 @@ struct GPUData {
 // Input side packet:
 //  CUSTOM_OP_RESOLVER (optional) - Use a custom op resolver,
 //                                  instead of the builtin one.
+//  MODEL (optional) - Use to specify TfLite model
+//                     (std::unique_ptr<tflite::FlatBufferModel,
+//                       std::function<void(tflite::FlatBufferModel*)>>)
 //
 // Example use:
 // node {
@@ -153,6 +179,20 @@ struct GPUData {
 //   }
 // }
 //
+// or
+//
+// node {
+//   calculator: "TfLiteInferenceCalculator"
+//   input_stream: "TENSORS:tensor_image"
+//   input_side_packet: "MODEL:model"
+//   output_stream: "TENSORS:tensors"
+//   options: {
+//     [mediapipe.TfLiteInferenceCalculatorOptions.ext] {
+//       delegate { gpu {} }
+//     }
+//   }
+// }
+//
 // IMPORTANT Notes:
 //  Tensors are assumed to be ordered correctly (sequentially added to model).
 //  Input tensors are assumed to be of the correct size and already normalized.
@@ -165,6 +205,9 @@ class TfLiteInferenceCalculator : public CalculatorBase {
  public:
   using TfLiteDelegatePtr =
       std::unique_ptr<TfLiteDelegate, std::function<void(TfLiteDelegate*)>>;
+  using TfLiteModelPtr =
+      std::unique_ptr<tflite::FlatBufferModel,
+                      std::function<void(tflite::FlatBufferModel*)>>;
 
   static ::mediapipe::Status GetContract(CalculatorContract* cc);
 
@@ -173,12 +216,12 @@ class TfLiteInferenceCalculator : public CalculatorBase {
   ::mediapipe::Status Close(CalculatorContext* cc) override;
 
  private:
-  ::mediapipe::Status LoadOptions(CalculatorContext* cc);
   ::mediapipe::Status LoadModel(CalculatorContext* cc);
+  ::mediapipe::StatusOr<Packet> GetModelAsPacket(const CalculatorContext& cc);
   ::mediapipe::Status LoadDelegate(CalculatorContext* cc);
 
+  Packet model_packet_;
   std::unique_ptr<tflite::Interpreter> interpreter_;
-  std::unique_ptr<tflite::FlatBufferModel> model_;
   TfLiteDelegatePtr delegate_;
 
 #if !defined(MEDIAPIPE_DISABLE_GL_COMPUTE)
@@ -198,7 +241,6 @@ class TfLiteInferenceCalculator : public CalculatorBase {
       edgetpu::EdgeTpuManager::GetSingleton()->OpenDevice();
 #endif
 
-  std::string model_path_ = "";
   bool gpu_inference_ = false;
   bool gpu_input_ = false;
   bool gpu_output_ = false;
@@ -217,6 +259,10 @@ REGISTER_CALCULATOR(TfLiteInferenceCalculator);
 
   const auto& options =
       cc->Options<::mediapipe::TfLiteInferenceCalculatorOptions>();
+  RET_CHECK(!options.model_path().empty() ^
+            cc->InputSidePackets().HasTag("MODEL"))
+      << "Either model as side packet or model path in options is required.";
+
   bool use_gpu =
       options.has_delegate() ? options.delegate().has_gpu() : options.use_gpu();
 
@@ -249,6 +295,9 @@ REGISTER_CALCULATOR(TfLiteInferenceCalculator);
         .Tag("CUSTOM_OP_RESOLVER")
         .Set<tflite::ops::builtin::BuiltinOpResolver>();
   }
+  if (cc->InputSidePackets().HasTag("MODEL")) {
+    cc->InputSidePackets().Tag("MODEL").Set<TfLiteModelPtr>();
+  }
 
   if (use_gpu) {
 #if !defined(MEDIAPIPE_DISABLE_GL_COMPUTE)
@@ -267,7 +316,9 @@ REGISTER_CALCULATOR(TfLiteInferenceCalculator);
 ::mediapipe::Status TfLiteInferenceCalculator::Open(CalculatorContext* cc) {
   cc->SetOffset(TimestampDiff(0));
 
-  MP_RETURN_IF_ERROR(LoadOptions(cc));
+  const auto& options =
+      cc->Options<::mediapipe::TfLiteInferenceCalculatorOptions>();
+  gpu_inference_ = options.use_gpu();
 
   if (cc->Inputs().HasTag("TENSORS_GPU")) {
 #if !defined(MEDIAPIPE_DISABLE_GPU) && !defined(__EMSCRIPTEN__)
@@ -492,34 +543,10 @@ REGISTER_CALCULATOR(TfLiteInferenceCalculator);
 
 // Calculator Auxiliary Section
 
-::mediapipe::Status TfLiteInferenceCalculator::LoadOptions(
-    CalculatorContext* cc) {
-  // Get calculator options specified in the graph.
-  const auto& options =
-      cc->Options<::mediapipe::TfLiteInferenceCalculatorOptions>();
-
-  // Get model name.
-  if (!options.model_path().empty()) {
-    std::string model_path = options.model_path();
-
-    ASSIGN_OR_RETURN(model_path_, mediapipe::PathToResourceAsFile(model_path));
-  } else {
-    LOG(ERROR) << "Must specify path to TFLite model.";
-    return ::mediapipe::Status(::mediapipe::StatusCode::kNotFound,
-                               "Must specify path to TFLite model.");
-  }
-
-  // Get execution modes.
-  gpu_inference_ =
-      options.has_delegate() ? options.delegate().has_gpu() : options.use_gpu();
-
-  return ::mediapipe::OkStatus();
-}
-
 ::mediapipe::Status TfLiteInferenceCalculator::LoadModel(
     CalculatorContext* cc) {
-  model_ = tflite::FlatBufferModel::BuildFromFile(model_path_.c_str());
+  ASSIGN_OR_RETURN(model_packet_, GetModelAsPacket(*cc));
-  RET_CHECK(model_);
+  const auto& model = *model_packet_.Get<TfLiteModelPtr>();
 
   tflite::ops::builtin::BuiltinOpResolver op_resolver;
   if (cc->InputSidePackets().HasTag("CUSTOM_OP_RESOLVER")) {
@@ -529,9 +556,9 @@ REGISTER_CALCULATOR(TfLiteInferenceCalculator);
   }
 #if defined(MEDIAPIPE_EDGE_TPU)
   interpreter_ =
-      BuildEdgeTpuInterpreter(*model_, &op_resolver, edgetpu_context_.get());
+      BuildEdgeTpuInterpreter(model, &op_resolver, edgetpu_context_.get());
 #else
-  tflite::InterpreterBuilder(*model_, op_resolver)(&interpreter_);
+  tflite::InterpreterBuilder(model, op_resolver)(&interpreter_);
 #endif  // MEDIAPIPE_EDGE_TPU
 
   RET_CHECK(interpreter_);
@@ -557,6 +584,28 @@ REGISTER_CALCULATOR(TfLiteInferenceCalculator);
   return ::mediapipe::OkStatus();
 }
 
+::mediapipe::StatusOr<Packet> TfLiteInferenceCalculator::GetModelAsPacket(
+    const CalculatorContext& cc) {
+  const auto& options =
+      cc.Options<mediapipe::TfLiteInferenceCalculatorOptions>();
+  if (!options.model_path().empty()) {
+    std::string model_path = options.model_path();
+
+    ASSIGN_OR_RETURN(model_path, mediapipe::PathToResourceAsFile(model_path));
+
+    auto model = tflite::FlatBufferModel::BuildFromFile(model_path.c_str());
+    RET_CHECK(model) << "Failed to load model from path.";
+    return MakePacket<TfLiteModelPtr>(TfLiteModelPtr(
+        model.release(), [](tflite::FlatBufferModel* model) { delete model; }));
+  }
+  if (cc.InputSidePackets().HasTag("MODEL")) {
+    return cc.InputSidePackets().Tag("MODEL");
+  }
+  return ::mediapipe::Status(
+      ::mediapipe::StatusCode::kNotFound,
+      "Must specify TFLite model as path or loaded model.");
+}
+
 ::mediapipe::Status TfLiteInferenceCalculator::LoadDelegate(
     CalculatorContext* cc) {
   const auto& calculator_opts =
@@ -587,6 +636,22 @@ REGISTER_CALCULATOR(TfLiteInferenceCalculator);
     }
 #endif  // MEDIAPIPE_ANDROID
 
+#if defined(__EMSCRIPTEN__)
+    const bool xnnpack_requested = true;
+#else
+    const bool xnnpack_requested = calculator_opts.has_delegate() &&
+                                   calculator_opts.delegate().has_xnnpack();
+#endif  // __EMSCRIPTEN__
+
+    if (xnnpack_requested) {
+      TfLiteXNNPackDelegateOptions xnnpack_opts{};
+      xnnpack_opts.num_threads = GetXnnpackNumThreads(calculator_opts);
+      delegate_ = TfLiteDelegatePtr(TfLiteXNNPackDelegateCreate(&xnnpack_opts),
+                                    &TfLiteXNNPackDelegateDelete);
+      RET_CHECK_EQ(interpreter_->ModifyGraphWithDelegate(delegate_.get()),
+                   kTfLiteOk);
+    }
+
     // Return, no need for GPU delegate below.
     return ::mediapipe::OkStatus();
   }

mediapipe/calculators/tflite/tflite_inference_calculator.proto

@@ -45,11 +45,17 @@ message TfLiteInferenceCalculatorOptions {
     message Gpu {}
     // Android only.
     message Nnapi {}
+    message Xnnpack {
+      // Number of threads for XNNPACK delegate. (By default, calculator tries
+      // to choose optimal number of threads depending on the device.)
+      optional int32 num_threads = 1 [default = -1];
+    }
 
     oneof delegate {
       TfLite tflite = 1;
       Gpu gpu = 2;
       Nnapi nnapi = 3;
+      Xnnpack xnnpack = 4;
     }
   }
 

mediapipe/calculators/tflite/tflite_inference_calculator_test.cc

@@ -41,7 +41,7 @@ namespace mediapipe {
 
 using ::tflite::Interpreter;
 
-void DoSmokeTest(absl::string_view delegate) {
+void DoSmokeTest(const std::string& graph_proto) {
   const int width = 8;
   const int height = 8;
   const int channels = 3;
@@ -69,24 +69,9 @@ void DoSmokeTest(absl::string_view delegate) {
   auto input_vec = absl::make_unique<std::vector<TfLiteTensor>>();
   input_vec->emplace_back(*tensor);
 
-  std::string graph_proto = R"(
-    input_stream: "tensor_in"
-    node {
-      calculator: "TfLiteInferenceCalculator"
-      input_stream: "TENSORS:tensor_in"
-      output_stream: "TENSORS:tensor_out"
-      options {
-        [mediapipe.TfLiteInferenceCalculatorOptions.ext] {
-          model_path: "mediapipe/calculators/tflite/testdata/add.bin"
-          $delegate
-        }
-      }
-    }
-  )";
-  ASSERT_EQ(absl::StrReplaceAll({{"$delegate", delegate}}, &graph_proto), 1);
   // Prepare single calculator graph to and wait for packets.
   CalculatorGraphConfig graph_config =
-      ::mediapipe::ParseTextProtoOrDie<CalculatorGraphConfig>(graph_proto);
+      ParseTextProtoOrDie<CalculatorGraphConfig>(graph_proto);
   std::vector<Packet> output_packets;
   tool::AddVectorSink("tensor_out", &graph_config, &output_packets);
   CalculatorGraph graph(graph_config);
@@ -119,8 +104,70 @@ void DoSmokeTest(absl::string_view delegate) {
 
 // Tests a simple add model that adds an input tensor to itself.
 TEST(TfLiteInferenceCalculatorTest, SmokeTest) {
-  DoSmokeTest(/*delegate=*/"");
+  std::string graph_proto = R"(
-  DoSmokeTest(/*delegate=*/"delegate { tflite {} }");
+    input_stream: "tensor_in"
+    node {
+      calculator: "TfLiteInferenceCalculator"
+      input_stream: "TENSORS:tensor_in"
+      output_stream: "TENSORS:tensor_out"
+      options {
+        [mediapipe.TfLiteInferenceCalculatorOptions.ext] {
+          model_path: "mediapipe/calculators/tflite/testdata/add.bin"
+          $delegate
+        }
+      }
+    }
+  )";
+  DoSmokeTest(
+      /*graph_proto=*/absl::StrReplaceAll(graph_proto, {{"$delegate", ""}}));
+  DoSmokeTest(/*graph_proto=*/absl::StrReplaceAll(
+      graph_proto, {{"$delegate", "delegate { tflite {} }"}}));
+  DoSmokeTest(/*graph_proto=*/absl::StrReplaceAll(
+      graph_proto, {{"$delegate", "delegate { xnnpack {} }"}}));
+  DoSmokeTest(/*graph_proto=*/absl::StrReplaceAll(
+      graph_proto,
+      {{"$delegate", "delegate { xnnpack { num_threads: 10 } }"}}));
+}
+
+TEST(TfLiteInferenceCalculatorTest, SmokeTest_ModelAsInputSidePacket) {
+  std::string graph_proto = R"(
+    input_stream: "tensor_in"
+
+    node {
+      calculator: "ConstantSidePacketCalculator"
+      output_side_packet: "PACKET:model_path"
+      options: {
+        [mediapipe.ConstantSidePacketCalculatorOptions.ext]: {
+          packet { string_value: "mediapipe/calculators/tflite/testdata/add.bin" }
+        }
+      }
+    }
+
+    node {
+      calculator: "LocalFileContentsCalculator"
+      input_side_packet: "FILE_PATH:model_path"
+      output_side_packet: "CONTENTS:model_blob"
+    }
+
+    node {
+      calculator: "TfLiteModelCalculator"
+      input_side_packet: "MODEL_BLOB:model_blob"
+      output_side_packet: "MODEL:model"
+    }
+
+    node {
+      calculator: "TfLiteInferenceCalculator"
+      input_stream: "TENSORS:tensor_in"
+      output_stream: "TENSORS:tensor_out"
+      input_side_packet: "MODEL:model"
+      options {
+        [mediapipe.TfLiteInferenceCalculatorOptions.ext] {
+          use_gpu: false
+        }
+      }
+    }
+  )";
+  DoSmokeTest(graph_proto);
 }
 
 }  // namespace mediapipe

mediapipe/calculators/tflite/tflite_model_calculator.cc

@@ -0,0 +1,86 @@
+// Copyright 2020 The MediaPipe Authors.
+//
+// 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 <functional>
+#include <memory>
+#include <string>
+
+#include "mediapipe/framework/calculator_framework.h"
+#include "mediapipe/framework/packet.h"
+#include "mediapipe/framework/port/ret_check.h"
+#include "tensorflow/lite/model.h"
+
+namespace mediapipe {
+
+// Loads TfLite model from model blob specified as input side packet and outputs
+// corresponding side packet.
+//
+// Input side packets:
+//   MODEL_BLOB - TfLite model blob/file-contents (std::string). You can read
+//                model blob from file (using whatever APIs you have) and pass
+//                it to the graph as input side packet or you can use some of
+//                calculators like LocalFileContentsCalculator to get model
+//                blob and use it as input here.
+//
+// Output side packets:
+//   MODEL - TfLite model. (std::unique_ptr<tflite::FlatBufferModel,
+//           std::function<void(tflite::FlatBufferModel*)>>)
+//
+// Example use:
+//
+// node {
+//   calculator: "TfLiteModelCalculator"
+//   input_side_packet: "MODEL_BLOB:model_blob"
+//   output_side_packet: "MODEL:model"
+// }
+//
+class TfLiteModelCalculator : public CalculatorBase {
+ public:
+  using TfLiteModelPtr =
+      std::unique_ptr<tflite::FlatBufferModel,
+                      std::function<void(tflite::FlatBufferModel*)>>;
+
+  static ::mediapipe::Status GetContract(CalculatorContract* cc) {
+    cc->InputSidePackets().Tag("MODEL_BLOB").Set<std::string>();
+    cc->OutputSidePackets().Tag("MODEL").Set<TfLiteModelPtr>();
+    return ::mediapipe::OkStatus();
+  }
+
+  ::mediapipe::Status Open(CalculatorContext* cc) override {
+    const Packet& model_packet = cc->InputSidePackets().Tag("MODEL_BLOB");
+    const std::string& model_blob = model_packet.Get<std::string>();
+    std::unique_ptr<tflite::FlatBufferModel> model =
+        tflite::FlatBufferModel::BuildFromBuffer(model_blob.data(),
+                                                 model_blob.size());
+    RET_CHECK(model) << "Failed to load TfLite model from blob.";
+
+    cc->OutputSidePackets().Tag("MODEL").Set(
+        MakePacket<TfLiteModelPtr>(TfLiteModelPtr(
+            model.release(), [model_packet](tflite::FlatBufferModel* model) {
+              // Keeping model_packet in order to keep underlying model blob
+              // which can be released only after TfLite model is not needed
+              // anymore (deleted).
+              delete model;
+            })));
+
+    return ::mediapipe::OkStatus();
+  }
+
+  ::mediapipe::Status Process(CalculatorContext* cc) override {
+    return ::mediapipe::OkStatus();
+  }
+};
+REGISTER_CALCULATOR(TfLiteModelCalculator);
+
+}  // namespace mediapipe

mediapipe/calculators/tflite/tflite_model_calculator_test.cc

@@ -0,0 +1,88 @@
+// Copyright 2020 The MediaPipe Authors.
+//
+// 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 "mediapipe/framework/calculator_framework.h"
+#include "mediapipe/framework/calculator_runner.h"
+#include "mediapipe/framework/port/gmock.h"
+#include "mediapipe/framework/port/gtest.h"
+#include "mediapipe/framework/port/parse_text_proto.h"
+#include "mediapipe/framework/port/status_matchers.h"  // NOLINT
+#include "tensorflow/lite/model.h"
+
+namespace mediapipe {
+
+TEST(TfLiteModelCalculatorTest, SmokeTest) {
+  // Prepare single calculator graph to and wait for packets.
+  CalculatorGraphConfig graph_config = ParseTextProtoOrDie<
+      CalculatorGraphConfig>(
+      R"(
+        node {
+          calculator: "ConstantSidePacketCalculator"
+          output_side_packet: "PACKET:model_path"
+          options: {
+            [mediapipe.ConstantSidePacketCalculatorOptions.ext]: {
+              packet {
+                string_value: "mediapipe/calculators/tflite/testdata/add.bin"
+              }
+            }
+          }
+        }
+
+        node {
+          calculator: "LocalFileContentsCalculator"
+          input_side_packet: "FILE_PATH:model_path"
+          output_side_packet: "CONTENTS:model_blob"
+        }
+
+        node {
+          calculator: "TfLiteModelCalculator"
+          input_side_packet: "MODEL_BLOB:model_blob"
+          output_side_packet: "MODEL:model"
+        }
+      )");
+  CalculatorGraph graph(graph_config);
+  MP_ASSERT_OK(graph.StartRun({}));
+  MP_ASSERT_OK(graph.WaitUntilIdle());
+  auto status_or_packet = graph.GetOutputSidePacket("model");
+  MP_ASSERT_OK(status_or_packet);
+  auto model_packet = status_or_packet.ValueOrDie();
+  const auto& model = model_packet.Get<
+      std::unique_ptr<tflite::FlatBufferModel,
+                      std::function<void(tflite::FlatBufferModel*)>>>();
+
+  auto expected_model = tflite::FlatBufferModel::BuildFromFile(
+      "mediapipe/calculators/tflite/testdata/add.bin");
+
+  EXPECT_EQ(model->GetModel()->version(),
+            expected_model->GetModel()->version());
+  EXPECT_EQ(model->GetModel()->buffers()->size(),
+            expected_model->GetModel()->buffers()->size());
+  const int num_subgraphs = expected_model->GetModel()->subgraphs()->size();
+  EXPECT_EQ(model->GetModel()->subgraphs()->size(), num_subgraphs);
+  for (int i = 0; i < num_subgraphs; ++i) {
+    const auto* expected_subgraph =
+        expected_model->GetModel()->subgraphs()->Get(i);
+    const auto* subgraph = model->GetModel()->subgraphs()->Get(i);
+    const int num_tensors = expected_subgraph->tensors()->size();
+    EXPECT_EQ(subgraph->tensors()->size(), num_tensors);
+    for (int j = 0; j < num_tensors; ++j) {
+      EXPECT_EQ(subgraph->tensors()->Get(j)->name()->str(),
+                expected_subgraph->tensors()->Get(j)->name()->str());
+    }
+  }
+}
+
+}  // namespace mediapipe

mediapipe/calculators/tflite/tflite_tensors_to_classification_calculator.cc

@@ -129,24 +129,45 @@ REGISTER_CALCULATOR(TfLiteTensorsToClassificationCalculator);
     num_classes *= raw_score_tensor->dims->data[i];
   }
 
+  if (options_.binary_classification()) {
+    RET_CHECK_EQ(num_classes, 1);
+    // Number of classes for binary classification.
+    num_classes = 2;
+  }
   if (label_map_loaded_) {
     RET_CHECK_EQ(num_classes, label_map_.size());
   }
   const float* raw_scores = raw_score_tensor->data.f;
 
   auto classification_list = absl::make_unique<ClassificationList>();
+  if (options_.binary_classification()) {
+    Classification* class_first = classification_list->add_classification();
+    Classification* class_second = classification_list->add_classification();
+    class_first->set_index(0);
+    class_second->set_index(1);
+    class_first->set_score(raw_scores[0]);
+    class_second->set_score(1. - raw_scores[0]);
+
+    if (label_map_loaded_) {
+      class_first->set_label(label_map_[0]);
+      class_second->set_label(label_map_[1]);
+    }
+  } else {
     for (int i = 0; i < num_classes; ++i) {
       if (options_.has_min_score_threshold() &&
           raw_scores[i] < options_.min_score_threshold()) {
         continue;
       }
-    Classification* classification = classification_list->add_classification();
+      Classification* classification =
+          classification_list->add_classification();
       classification->set_index(i);
       classification->set_score(raw_scores[i]);
+
       if (label_map_loaded_) {
         classification->set_label(label_map_[i]);
       }
     }
+  }
 
   // Note that partial_sort will raise error when top_k_ >
   // classification_list->classification_size().

mediapipe/calculators/tflite/tflite_tensors_to_classification_calculator.proto

@@ -32,4 +32,10 @@ message TfLiteTensorsToClassificationCalculatorOptions {
   optional int32 top_k = 2;
   // Path to a label map file for getting the actual name of class ids.
   optional string label_map_path = 3;
+  // Whether the input is a single float for binary classification.
+  // When true, only a single float is expected in the input tensor and the
+  // label map, if provided, is expected to have exactly two labels.
+  // The single score(float) represent the probability of first label, and
+  // 1 - score is the probabilility of the second label.
+  optional bool binary_classification = 4;
 }

mediapipe/calculators/util/BUILD

@@ -998,6 +998,7 @@ cc_library(
     visibility = ["//visibility:public"],
     deps = [
         "//mediapipe/framework:calculator_framework",
+        "//mediapipe/framework/formats:classification_cc_proto",
         "//mediapipe/framework/formats:landmark_cc_proto",
         "//mediapipe/framework/formats:rect_cc_proto",
         "//mediapipe/framework/port:ret_check",
@@ -1015,6 +1016,7 @@ cc_library(
     deps = [
         ":collection_has_min_size_calculator_cc_proto",
         "//mediapipe/framework:calculator_framework",
+        "//mediapipe/framework/formats:landmark_cc_proto",
         "//mediapipe/framework/formats:rect_cc_proto",
         "//mediapipe/framework/port:ret_check",
         "//mediapipe/framework/port:status",
@@ -1022,6 +1024,18 @@ cc_library(
     alwayslink = 1,
 )
 
+cc_test(
+    name = "collection_has_min_size_calculator_test",
+    srcs = ["collection_has_min_size_calculator_test.cc"],
+    deps = [
+        ":collection_has_min_size_calculator",
+        "//mediapipe/framework:calculator_framework",
+        "//mediapipe/framework:calculator_runner",
+        "//mediapipe/framework/port:gtest_main",
+        "//mediapipe/framework/port:parse_text_proto",
+    ],
+)
+
 cc_library(
     name = "association_calculator",
     hdrs = ["association_calculator.h"],

mediapipe/calculators/util/collection_has_min_size_calculator.cc

@@ -15,6 +15,9 @@
 
 #include "mediapipe/calculators/util/collection_has_min_size_calculator.h"
 
+#include <vector>
+
+#include "mediapipe/framework/formats/landmark.pb.h"
 #include "mediapipe/framework/formats/rect.pb.h"
 
 namespace mediapipe {
@@ -23,4 +26,9 @@ typedef CollectionHasMinSizeCalculator<std::vector<::mediapipe::NormalizedRect>>
     NormalizedRectVectorHasMinSizeCalculator;
 REGISTER_CALCULATOR(NormalizedRectVectorHasMinSizeCalculator);
 
+typedef CollectionHasMinSizeCalculator<
+    std::vector<::mediapipe::NormalizedLandmarkList>>
+    NormalizedLandmarkListVectorHasMinSizeCalculator;
+REGISTER_CALCULATOR(NormalizedLandmarkListVectorHasMinSizeCalculator);
+
 }  // namespace mediapipe

mediapipe/calculators/util/collection_has_min_size_calculator_test.cc

@@ -0,0 +1,156 @@
+// Copyright 2020 The MediaPipe Authors.
+//
+// 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/calculators/util/collection_has_min_size_calculator.h"
+
+#include <memory>
+#include <string>
+#include <vector>
+
+#include "mediapipe/framework/calculator_framework.h"
+#include "mediapipe/framework/calculator_runner.h"
+#include "mediapipe/framework/port/gmock.h"
+#include "mediapipe/framework/port/gtest.h"
+#include "mediapipe/framework/port/parse_text_proto.h"
+#include "mediapipe/framework/port/status_matchers.h"  // NOLINT
+
+namespace mediapipe {
+
+typedef CollectionHasMinSizeCalculator<std::vector<int>>
+    TestIntCollectionHasMinSizeCalculator;
+REGISTER_CALCULATOR(TestIntCollectionHasMinSizeCalculator);
+
+void AddInputVector(const std::vector<int>& input, int64 timestamp,
+                    CalculatorRunner* runner) {
+  runner->MutableInputs()
+      ->Tag("ITERABLE")
+      .packets.push_back(
+          MakePacket<std::vector<int>>(input).At(Timestamp(timestamp)));
+}
+
+TEST(TestIntCollectionHasMinSizeCalculator, DoesHaveMinSize) {
+  CalculatorGraphConfig::Node node_config =
+      ParseTextProtoOrDie<CalculatorGraphConfig::Node>(R"(
+        calculator: "TestIntCollectionHasMinSizeCalculator"
+        input_stream: "ITERABLE:input_vector"
+        output_stream: "output_vector"
+        options {
+          [mediapipe.CollectionHasMinSizeCalculatorOptions.ext] { min_size: 2 }
+        }
+      )");
+  CalculatorRunner runner(node_config);
+  const std::vector<Packet>& outputs = runner.Outputs().Index(0).packets;
+
+  AddInputVector({1, 2}, /*timestamp=*/1, &runner);
+  MP_ASSERT_OK(runner.Run());
+
+  EXPECT_EQ(1, outputs.size());
+  EXPECT_EQ(Timestamp(1), outputs[0].Timestamp());
+  EXPECT_TRUE(outputs[0].Get<bool>());
+
+  AddInputVector({1, 2, 3}, /*timestamp=*/2, &runner);
+  MP_ASSERT_OK(runner.Run());
+
+  EXPECT_EQ(2, outputs.size());
+  EXPECT_EQ(Timestamp(2), outputs[1].Timestamp());
+  EXPECT_TRUE(outputs[1].Get<bool>());
+}
+
+TEST(TestIntCollectionHasMinSizeCalculator,
+     DoesHaveMinSize_MinSizeAsSidePacket) {
+  CalculatorGraphConfig::Node node_config =
+      ParseTextProtoOrDie<CalculatorGraphConfig::Node>(R"(
+        calculator: "TestIntCollectionHasMinSizeCalculator"
+        input_stream: "ITERABLE:input_vector"
+        input_side_packet: "min_size"
+        output_stream: "output_vector"
+      )");
+  CalculatorRunner runner(node_config);
+  const std::vector<Packet>& outputs = runner.Outputs().Index(0).packets;
+
+  runner.MutableSidePackets()->Index(0) = MakePacket<int>(2);
+
+  AddInputVector({1, 2}, /*timestamp=*/1, &runner);
+  MP_ASSERT_OK(runner.Run());
+
+  EXPECT_EQ(1, outputs.size());
+  EXPECT_EQ(Timestamp(1), outputs[0].Timestamp());
+  EXPECT_TRUE(outputs[0].Get<bool>());
+
+  AddInputVector({1, 2, 3}, /*timestamp=*/2, &runner);
+  MP_ASSERT_OK(runner.Run());
+
+  EXPECT_EQ(2, outputs.size());
+  EXPECT_EQ(Timestamp(2), outputs[1].Timestamp());
+  EXPECT_TRUE(outputs[1].Get<bool>());
+}
+
+TEST(TestIntCollectionHasMinSizeCalculator, DoesNotHaveMinSize) {
+  CalculatorGraphConfig::Node node_config =
+      ParseTextProtoOrDie<CalculatorGraphConfig::Node>(R"(
+        calculator: "TestIntCollectionHasMinSizeCalculator"
+        input_stream: "ITERABLE:input_vector"
+        output_stream: "output_vector"
+        options {
+          [mediapipe.CollectionHasMinSizeCalculatorOptions.ext] { min_size: 3 }
+        }
+      )");
+  CalculatorRunner runner(node_config);
+  const std::vector<Packet>& outputs = runner.Outputs().Index(0).packets;
+
+  AddInputVector({1}, /*timestamp=*/1, &runner);
+  MP_ASSERT_OK(runner.Run());
+
+  EXPECT_EQ(1, outputs.size());
+  EXPECT_EQ(Timestamp(1), outputs[0].Timestamp());
+  EXPECT_FALSE(outputs[0].Get<bool>());
+
+  AddInputVector({1, 2}, /*timestamp=*/2, &runner);
+  MP_ASSERT_OK(runner.Run());
+
+  EXPECT_EQ(2, outputs.size());
+  EXPECT_EQ(Timestamp(2), outputs[1].Timestamp());
+  EXPECT_FALSE(outputs[1].Get<bool>());
+}
+
+TEST(TestIntCollectionHasMinSizeCalculator,
+     DoesNotHaveMinSize_MinSizeAsSidePacket) {
+  CalculatorGraphConfig::Node node_config =
+      ParseTextProtoOrDie<CalculatorGraphConfig::Node>(R"(
+        calculator: "TestIntCollectionHasMinSizeCalculator"
+        input_stream: "ITERABLE:input_vector"
+        input_side_packet: "min_size"
+        output_stream: "output_vector"
+      )");
+  CalculatorRunner runner(node_config);
+  const std::vector<Packet>& outputs = runner.Outputs().Index(0).packets;
+
+  runner.MutableSidePackets()->Index(0) = MakePacket<int>(3);
+
+  AddInputVector({1}, /*timestamp=*/1, &runner);
+  MP_ASSERT_OK(runner.Run());
+
+  EXPECT_EQ(1, outputs.size());
+  EXPECT_EQ(Timestamp(1), outputs[0].Timestamp());
+  EXPECT_FALSE(outputs[0].Get<bool>());
+
+  AddInputVector({1, 2}, /*timestamp=*/2, &runner);
+  MP_ASSERT_OK(runner.Run());
+
+  EXPECT_EQ(2, outputs.size());
+  EXPECT_EQ(Timestamp(2), outputs[1].Timestamp());
+  EXPECT_FALSE(outputs[1].Get<bool>());
+}
+
+}  // namespace mediapipe

mediapipe/calculators/util/filter_collection_calculator.cc

@@ -17,6 +17,7 @@
 
 #include <vector>
 
+#include "mediapipe/framework/formats/classification.pb.h"
 #include "mediapipe/framework/formats/landmark.pb.h"
 #include "mediapipe/framework/formats/rect.pb.h"
 
@@ -31,4 +32,8 @@ typedef FilterCollectionCalculator<
     FilterLandmarkListCollectionCalculator;
 REGISTER_CALCULATOR(FilterLandmarkListCollectionCalculator);
 
+typedef FilterCollectionCalculator<std::vector<::mediapipe::ClassificationList>>
+    FilterClassificationListCollectionCalculator;
+REGISTER_CALCULATOR(FilterClassificationListCollectionCalculator);
+
 }  // namespace mediapipe

mediapipe/calculators/util/landmarks_to_render_data_calculator.cc

@@ -29,6 +29,7 @@ namespace {
 
 constexpr char kLandmarksTag[] = "LANDMARKS";
 constexpr char kNormLandmarksTag[] = "NORM_LANDMARKS";
+constexpr char kRenderScaleTag[] = "RENDER_SCALE";
 constexpr char kRenderDataTag[] = "RENDER_DATA";
 constexpr char kLandmarkLabel[] = "KEYPOINT";
 constexpr int kMaxLandmarkThickness = 18;
@@ -71,6 +72,83 @@ void SetColorSizeValueFromZ(float z, float z_min, float z_max,
   render_annotation->set_thickness(thickness);
 }
 
+template <class LandmarkType>
+void AddConnectionToRenderData(const LandmarkType& start,
+                               const LandmarkType& end, int gray_val1,
+                               int gray_val2, float thickness, bool normalized,
+                               RenderData* render_data) {
+  auto* connection_annotation = render_data->add_render_annotations();
+  RenderAnnotation::GradientLine* line =
+      connection_annotation->mutable_gradient_line();
+  line->set_x_start(start.x());
+  line->set_y_start(start.y());
+  line->set_x_end(end.x());
+  line->set_y_end(end.y());
+  line->set_normalized(normalized);
+  line->mutable_color1()->set_r(gray_val1);
+  line->mutable_color1()->set_g(gray_val1);
+  line->mutable_color1()->set_b(gray_val1);
+  line->mutable_color2()->set_r(gray_val2);
+  line->mutable_color2()->set_g(gray_val2);
+  line->mutable_color2()->set_b(gray_val2);
+  connection_annotation->set_thickness(thickness);
+}
+
+template <class LandmarkListType, class LandmarkType>
+void AddConnectionsWithDepth(const LandmarkListType& landmarks,
+                             const std::vector<int>& landmark_connections,
+                             float thickness, bool normalized, float min_z,
+                             float max_z, RenderData* render_data) {
+  for (int i = 0; i < landmark_connections.size(); i += 2) {
+    const auto& ld0 = landmarks.landmark(landmark_connections[i]);
+    const auto& ld1 = landmarks.landmark(landmark_connections[i + 1]);
+    const int gray_val1 =
+        255 - static_cast<int>(Remap(ld0.z(), min_z, max_z, 255));
+    const int gray_val2 =
+        255 - static_cast<int>(Remap(ld1.z(), min_z, max_z, 255));
+    AddConnectionToRenderData<LandmarkType>(ld0, ld1, gray_val1, gray_val2,
+                                            thickness, normalized, render_data);
+  }
+}
+
+template <class LandmarkType>
+void AddConnectionToRenderData(const LandmarkType& start,
+                               const LandmarkType& end,
+                               const Color& connection_color, float thickness,
+                               bool normalized, RenderData* render_data) {
+  auto* connection_annotation = render_data->add_render_annotations();
+  RenderAnnotation::Line* line = connection_annotation->mutable_line();
+  line->set_x_start(start.x());
+  line->set_y_start(start.y());
+  line->set_x_end(end.x());
+  line->set_y_end(end.y());
+  line->set_normalized(normalized);
+  SetColor(connection_annotation, connection_color);
+  connection_annotation->set_thickness(thickness);
+}
+
+template <class LandmarkListType, class LandmarkType>
+void AddConnections(const LandmarkListType& landmarks,
+                    const std::vector<int>& landmark_connections,
+                    const Color& connection_color, float thickness,
+                    bool normalized, RenderData* render_data) {
+  for (int i = 0; i < landmark_connections.size(); i += 2) {
+    const auto& ld0 = landmarks.landmark(landmark_connections[i]);
+    const auto& ld1 = landmarks.landmark(landmark_connections[i + 1]);
+    AddConnectionToRenderData<LandmarkType>(ld0, ld1, connection_color,
+                                            thickness, normalized, render_data);
+  }
+}
+
+RenderAnnotation* AddPointRenderData(const Color& landmark_color,
+                                     float thickness, RenderData* render_data) {
+  auto* landmark_data_annotation = render_data->add_render_annotations();
+  landmark_data_annotation->set_scene_tag(kLandmarkLabel);
+  SetColor(landmark_data_annotation, landmark_color);
+  landmark_data_annotation->set_thickness(thickness);
+  return landmark_data_annotation;
+}
+
 }  // namespace
 
 // A calculator that converts Landmark proto to RenderData proto for
@@ -107,29 +185,6 @@ class LandmarksToRenderDataCalculator : public CalculatorBase {
   ::mediapipe::Status Process(CalculatorContext* cc) override;
 
  private:
-  static void AddConnectionToRenderData(
-      float start_x, float start_y, float end_x, float end_y,
-      const LandmarksToRenderDataCalculatorOptions& options, bool normalized,
-      RenderData* render_data);
-  static void SetRenderAnnotationColorThickness(
-      const LandmarksToRenderDataCalculatorOptions& options,
-      RenderAnnotation* render_annotation);
-  static RenderAnnotation* AddPointRenderData(
-      const LandmarksToRenderDataCalculatorOptions& options,
-      RenderData* render_data);
-  static void AddConnectionToRenderData(
-      float start_x, float start_y, float end_x, float end_y,
-      const LandmarksToRenderDataCalculatorOptions& options, bool normalized,
-      int gray_val1, int gray_val2, RenderData* render_data);
-
-  template <class LandmarkListType>
-  void AddConnections(const LandmarkListType& landmarks, bool normalized,
-                      RenderData* render_data);
-  template <class LandmarkListType>
-  void AddConnectionsWithDepth(const LandmarkListType& landmarks,
-                               bool normalized, float min_z, float max_z,
-                               RenderData* render_data);
-
   LandmarksToRenderDataCalculatorOptions options_;
 };
 REGISTER_CALCULATOR(LandmarksToRenderDataCalculator);
@@ -150,6 +205,9 @@ REGISTER_CALCULATOR(LandmarksToRenderDataCalculator);
   if (cc->Inputs().HasTag(kNormLandmarksTag)) {
     cc->Inputs().Tag(kNormLandmarksTag).Set<NormalizedLandmarkList>();
   }
+  if (cc->Inputs().HasTag(kRenderScaleTag)) {
+    cc->Inputs().Tag(kRenderScaleTag).Set<float>();
+  }
   cc->Outputs().Tag(kRenderDataTag).Set<RenderData>();
   return ::mediapipe::OkStatus();
 }
@@ -169,11 +227,26 @@ REGISTER_CALCULATOR(LandmarksToRenderDataCalculator);
   float z_min = 0.f;
   float z_max = 0.f;
 
+  // Apply scale to `thickness` of rendered landmarks and connections to make
+  // them bigger when object (e.g. pose, hand or face) is closer/bigger and
+  // snaller when object is further/smaller.
+  float thickness = options_.thickness();
+  if (cc->Inputs().HasTag(kRenderScaleTag)) {
+    const float render_scale = cc->Inputs().Tag(kRenderScaleTag).Get<float>();
+    thickness *= render_scale;
+  }
+
+  // Parse landmarks connections to a vector.
+  RET_CHECK_EQ(options_.landmark_connections_size() % 2, 0)
+      << "Number of entries in landmark connections must be a multiple of 2";
+  std::vector<int> landmark_connections;
+  for (int i = 0; i < options_.landmark_connections_size(); i += 1) {
+    landmark_connections.push_back(options_.landmark_connections(i));
+  }
+
   if (cc->Inputs().HasTag(kLandmarksTag)) {
     const LandmarkList& landmarks =
         cc->Inputs().Tag(kLandmarksTag).Get<LandmarkList>();
-    RET_CHECK_EQ(options_.landmark_connections_size() % 2, 0)
-        << "Number of entries in landmark connections must be a multiple of 2";
     if (visualize_depth) {
       GetMinMaxZ<LandmarkList, Landmark>(landmarks, &z_min, &z_max);
     }
@@ -181,8 +254,8 @@ REGISTER_CALCULATOR(LandmarksToRenderDataCalculator);
     visualize_depth &= ((z_max - z_min) > 1e-3);
     for (int i = 0; i < landmarks.landmark_size(); ++i) {
       const Landmark& landmark = landmarks.landmark(i);
-      auto* landmark_data_render =
+      auto* landmark_data_render = AddPointRenderData(
-          AddPointRenderData(options_, render_data.get());
+          options_.landmark_color(), thickness, render_data.get());
       if (visualize_depth) {
         SetColorSizeValueFromZ(landmark.z(), z_min, z_max,
                                landmark_data_render);
@@ -193,19 +266,19 @@ REGISTER_CALCULATOR(LandmarksToRenderDataCalculator);
       landmark_data->set_y(landmark.y());
     }
     if (visualize_depth) {
-      AddConnectionsWithDepth<LandmarkList>(landmarks, /*normalized=*/false,
+      AddConnectionsWithDepth<LandmarkList, Landmark>(
+          landmarks, landmark_connections, thickness, /*normalized=*/false,
           z_min, z_max, render_data.get());
     } else {
-      AddConnections<LandmarkList>(landmarks, /*normalized=*/false,
+      AddConnections<LandmarkList, Landmark>(
-                                   render_data.get());
+          landmarks, landmark_connections, options_.connection_color(),
+          thickness, /*normalized=*/false, render_data.get());
     }
   }
 
   if (cc->Inputs().HasTag(kNormLandmarksTag)) {
     const NormalizedLandmarkList& landmarks =
         cc->Inputs().Tag(kNormLandmarksTag).Get<NormalizedLandmarkList>();
-    RET_CHECK_EQ(options_.landmark_connections_size() % 2, 0)
-        << "Number of entries in landmark connections must be a multiple of 2";
     if (visualize_depth) {
       GetMinMaxZ<NormalizedLandmarkList, NormalizedLandmark>(landmarks, &z_min,
                                                              &z_max);
@@ -214,8 +287,8 @@ REGISTER_CALCULATOR(LandmarksToRenderDataCalculator);
     visualize_depth &= ((z_max - z_min) > 1e-3);
     for (int i = 0; i < landmarks.landmark_size(); ++i) {
       const NormalizedLandmark& landmark = landmarks.landmark(i);
-      auto* landmark_data_render =
+      auto* landmark_data_render = AddPointRenderData(
-          AddPointRenderData(options_, render_data.get());
+          options_.landmark_color(), thickness, render_data.get());
       if (visualize_depth) {
         SetColorSizeValueFromZ(landmark.z(), z_min, z_max,
                                landmark_data_render);
@@ -226,11 +299,13 @@ REGISTER_CALCULATOR(LandmarksToRenderDataCalculator);
       landmark_data->set_y(landmark.y());
     }
     if (visualize_depth) {
-      AddConnectionsWithDepth<NormalizedLandmarkList>(
+      AddConnectionsWithDepth<NormalizedLandmarkList, NormalizedLandmark>(
-          landmarks, /*normalized=*/true, z_min, z_max, render_data.get());
+          landmarks, landmark_connections, thickness, /*normalized=*/true,
+          z_min, z_max, render_data.get());
     } else {
-      AddConnections<NormalizedLandmarkList>(landmarks, /*normalized=*/true,
+      AddConnections<NormalizedLandmarkList, NormalizedLandmark>(
-                                             render_data.get());
+          landmarks, landmark_connections, options_.connection_color(),
+          thickness, /*normalized=*/true, render_data.get());
     }
   }
 
@@ -240,84 +315,4 @@ REGISTER_CALCULATOR(LandmarksToRenderDataCalculator);
   return ::mediapipe::OkStatus();
 }
 
-template <class LandmarkListType>
-void LandmarksToRenderDataCalculator::AddConnectionsWithDepth(
-    const LandmarkListType& landmarks, bool normalized, float min_z,
-    float max_z, RenderData* render_data) {
-  for (int i = 0; i < options_.landmark_connections_size(); i += 2) {
-    const auto& ld0 = landmarks.landmark(options_.landmark_connections(i));
-    const auto& ld1 = landmarks.landmark(options_.landmark_connections(i + 1));
-    const int gray_val1 =
-        255 - static_cast<int>(Remap(ld0.z(), min_z, max_z, 255));
-    const int gray_val2 =
-        255 - static_cast<int>(Remap(ld1.z(), min_z, max_z, 255));
-    AddConnectionToRenderData(ld0.x(), ld0.y(), ld1.x(), ld1.y(), options_,
-                              normalized, gray_val1, gray_val2, render_data);
-  }
-}
-
-void LandmarksToRenderDataCalculator::AddConnectionToRenderData(
-    float start_x, float start_y, float end_x, float end_y,
-    const LandmarksToRenderDataCalculatorOptions& options, bool normalized,
-    int gray_val1, int gray_val2, RenderData* render_data) {
-  auto* connection_annotation = render_data->add_render_annotations();
-  RenderAnnotation::GradientLine* line =
-      connection_annotation->mutable_gradient_line();
-  line->set_x_start(start_x);
-  line->set_y_start(start_y);
-  line->set_x_end(end_x);
-  line->set_y_end(end_y);
-  line->set_normalized(normalized);
-  line->mutable_color1()->set_r(gray_val1);
-  line->mutable_color1()->set_g(gray_val1);
-  line->mutable_color1()->set_b(gray_val1);
-  line->mutable_color2()->set_r(gray_val2);
-  line->mutable_color2()->set_g(gray_val2);
-  line->mutable_color2()->set_b(gray_val2);
-  connection_annotation->set_thickness(options.thickness());
-}
-
-template <class LandmarkListType>
-void LandmarksToRenderDataCalculator::AddConnections(
-    const LandmarkListType& landmarks, bool normalized,
-    RenderData* render_data) {
-  for (int i = 0; i < options_.landmark_connections_size(); i += 2) {
-    const auto& ld0 = landmarks.landmark(options_.landmark_connections(i));
-    const auto& ld1 = landmarks.landmark(options_.landmark_connections(i + 1));
-    AddConnectionToRenderData(ld0.x(), ld0.y(), ld1.x(), ld1.y(), options_,
-                              normalized, render_data);
-  }
-}
-
-void LandmarksToRenderDataCalculator::AddConnectionToRenderData(
-    float start_x, float start_y, float end_x, float end_y,
-    const LandmarksToRenderDataCalculatorOptions& options, bool normalized,
-    RenderData* render_data) {
-  auto* connection_annotation = render_data->add_render_annotations();
-  RenderAnnotation::Line* line = connection_annotation->mutable_line();
-  line->set_x_start(start_x);
-  line->set_y_start(start_y);
-  line->set_x_end(end_x);
-  line->set_y_end(end_y);
-  line->set_normalized(normalized);
-  SetColor(connection_annotation, options.connection_color());
-  connection_annotation->set_thickness(options.thickness());
-}
-
-RenderAnnotation* LandmarksToRenderDataCalculator::AddPointRenderData(
-    const LandmarksToRenderDataCalculatorOptions& options,
-    RenderData* render_data) {
-  auto* landmark_data_annotation = render_data->add_render_annotations();
-  landmark_data_annotation->set_scene_tag(kLandmarkLabel);
-  SetRenderAnnotationColorThickness(options, landmark_data_annotation);
-  return landmark_data_annotation;
-}
-
-void LandmarksToRenderDataCalculator::SetRenderAnnotationColorThickness(
-    const LandmarksToRenderDataCalculatorOptions& options,
-    RenderAnnotation* render_annotation) {
-  SetColor(render_annotation, options.landmark_color());
-  render_annotation->set_thickness(options.thickness());
-}
-
 }  // namespace mediapipe

mediapipe/calculators/util/packet_latency_calculator_test.cc

@@ -276,6 +276,7 @@ TEST_F(PacketLatencyCalculatorTest, DoesNotOutputUntilReferencePacketReceived) {
       "delayed_packet_0", Adopt(new double()).At(Timestamp(2))));
 
   // Send a reference packet with timestamp 10 usec.
+  simulation_clock_->Sleep(absl::Microseconds(1));
   MP_ASSERT_OK(graph_.AddPacketToInputStream(
       "camera_frames", Adopt(new double()).At(Timestamp(10))));
   simulation_clock_->Sleep(absl::Microseconds(1));

mediapipe/calculators/video/BUILD

@@ -138,7 +138,7 @@ cc_library(
     srcs = ["flow_to_image_calculator.cc"],
     visibility = ["//visibility:public"],
     deps = [
-        "//mediapipe/calculators/video:flow_to_image_calculator_cc_proto",
+        ":flow_to_image_calculator_cc_proto",
         "//mediapipe/calculators/video/tool:flow_quantizer_model",
         "//mediapipe/framework:calculator_framework",
         "//mediapipe/framework/formats:image_format_cc_proto",
@@ -384,20 +384,18 @@ cc_test(
     ],
 )
 
-MEDIAPIPE_DEPS = [
-    "//mediapipe/calculators/video:box_tracker_calculator",
-    "//mediapipe/calculators/video:flow_packager_calculator",
-    "//mediapipe/calculators/video:motion_analysis_calculator",
-    "//mediapipe/framework/stream_handler:fixed_size_input_stream_handler",
-    "//mediapipe/framework/stream_handler:sync_set_input_stream_handler",
-]
-
 mediapipe_binary_graph(
     name = "parallel_tracker_binarypb",
     graph = "testdata/parallel_tracker_graph.pbtxt",
     output_name = "testdata/parallel_tracker.binarypb",
     visibility = ["//visibility:public"],
-    deps = MEDIAPIPE_DEPS,
+    deps = [
+        ":box_tracker_calculator",
+        ":flow_packager_calculator",
+        ":motion_analysis_calculator",
+        "//mediapipe/framework/stream_handler:fixed_size_input_stream_handler",
+        "//mediapipe/framework/stream_handler:sync_set_input_stream_handler",
+    ],
 )
 
 mediapipe_binary_graph(
@@ -405,7 +403,13 @@ mediapipe_binary_graph(
     graph = "testdata/tracker_graph.pbtxt",
     output_name = "testdata/tracker.binarypb",
     visibility = ["//visibility:public"],
-    deps = MEDIAPIPE_DEPS,
+    deps = [
+        ":box_tracker_calculator",
+        ":flow_packager_calculator",
+        ":motion_analysis_calculator",
+        "//mediapipe/framework/stream_handler:fixed_size_input_stream_handler",
+        "//mediapipe/framework/stream_handler:sync_set_input_stream_handler",
+    ],
 )
 
 cc_test(

mediapipe/examples/android/src/java/com/google/mediapipe/apps/METADATA

@@ -0,0 +1,7 @@
+tricorder: {
+  options: {
+    builder: {
+      config: "android_arm64"
+    }
+  }
+}

mediapipe/examples/desktop/autoflip/quality/polynomial_regression_path_solver.cc

@@ -95,7 +95,7 @@ void PolynomialRegressionPathSolver::AddCostFunctionToProblem(
     const std::vector<FocusPointFrame>& focus_point_frames,
     const std::vector<FocusPointFrame>& prior_focus_point_frames,
     const int original_width, const int original_height, const int output_width,
-    const int output_height, std::vector<cv::Mat>* all_xforms) {
+    const int output_height, std::vector<cv::Mat>* all_transforms) {
   RET_CHECK_GE(original_width, output_width);
   RET_CHECK_GE(original_height, output_height);
   const bool should_solve_x_problem = original_width != output_width;
@@ -138,9 +138,10 @@ void PolynomialRegressionPathSolver::AddCostFunctionToProblem(
   Solver::Options options;
   options.linear_solver_type = ceres::DENSE_QR;
 
-  Solver::Summary summary;
+  Solver::Summary summary_x, summary_y;
-  Solve(options, &problem_x, &summary);
+  Solve(options, &problem_x, &summary_x);
-  all_xforms->clear();
+  Solve(options, &problem_y, &summary_y);
+  all_transforms->clear();
   for (int i = 0;
        i < focus_point_frames.size() + prior_focus_point_frames.size(); i++) {
     // Code below assigns values into an affine model, defined as:
@@ -160,7 +161,7 @@ void PolynomialRegressionPathSolver::AddCostFunctionToProblem(
                                        yb_, yc_, yd_, yk_);
       transform.at<float>(1, 2) = delta;
     }
-    all_xforms->push_back(transform);
+    all_transforms->push_back(transform);
   }
   return mediapipe::OkStatus();
 }

mediapipe/examples/desktop/autoflip/quality/polynomial_regression_path_solver.h

@@ -40,14 +40,14 @@ class PolynomialRegressionPathSolver {
   // Given a series of focus points on frames, uses polynomial regression to
   // compute a best guess of a 1D camera movement trajectory along x-axis and
   // y-axis, such that focus points can be preserved as much as possible. The
-  // returned |all_xforms| hold the camera location at each timestamp
+  // returned |all_transforms| hold the camera location at each timestamp
   // corresponding to each input frame.
   ::mediapipe::Status ComputeCameraPath(
       const std::vector<FocusPointFrame>& focus_point_frames,
       const std::vector<FocusPointFrame>& prior_focus_point_frames,
       const int original_width, const int original_height,
       const int output_width, const int output_height,
-      std::vector<cv::Mat>* all_xforms);
+      std::vector<cv::Mat>* all_transforms);
 
  private:
   // Adds a new cost function, constructed using |in| and |out|, into |problem|.

mediapipe/examples/desktop/hair_segmentation/BUILD

@@ -24,3 +24,17 @@ cc_binary(
         "//mediapipe/graphs/hair_segmentation:mobile_calculators",
     ],
 )
+
+cc_binary(
+    name = "hair_segmentation_cpu",
+    deps = [
+        "//mediapipe/examples/desktop:demo_run_graph_main",
+    ] + select({
+        "//mediapipe/gpu:disable_gpu": [
+            "//mediapipe/graphs/hair_segmentation:desktop_calculators",
+        ],
+        "//conditions:default": [
+            "//mediapipe/graphs/hair_segmentation:mobile_calculators",
+        ],
+    }),
+)

mediapipe/framework/BUILD

@@ -361,6 +361,7 @@ cc_library(
         "//mediapipe/framework:mediapipe_options_cc_proto",
         "//mediapipe/framework:packet_generator_cc_proto",
         "//mediapipe/framework:status_handler_cc_proto",
+        "//mediapipe/framework:stream_handler_cc_proto",
         "//mediapipe/framework/port:any_proto",
         "//mediapipe/framework/port:status",
         "//mediapipe/framework/tool:options_util",

mediapipe/framework/calculator_contract.h

@@ -84,7 +84,7 @@ class CalculatorContract {
     return *output_side_packets_;
   }
 
-  // Set this Node's default InputStreamHandler.
+  // Specifies the preferred InputStreamHandler for this Node.
   // If there is an InputStreamHandler specified in the graph (.pbtxt) for this
   // Node, then the graph's InputStreamHandler will take priority.
   void SetInputStreamHandler(const std::string& name) {
@@ -104,6 +104,29 @@ class CalculatorContract {
     return input_stream_handler_options_;
   }
 
+  // The next few methods are concerned with timestamp bound propagation
+  // (see scheduling_sync.md#input-policies). Every calculator that processes
+  // live inputs should specify either ProcessTimestampBounds or
+  // TimestampOffset.  Calculators that produce output at the same timestamp as
+  // the input, or with a fixed offset, should declare this fact using
+  // SetTimestampOffset.  Calculators that require custom timestamp bound
+  // calculations should use SetProcessTimestampBounds.
+
+  // When true, Process is called for every new timestamp bound, with or without
+  // new packets.  A call to Process with only an input timestamp bound is
+  // normally used to compute a new output timestamp bound.
+  void SetProcessTimestampBounds(bool process_timestamps) {
+    process_timestamps_ = process_timestamps;
+  }
+  bool GetProcessTimestampBounds() const { return process_timestamps_; }
+
+  // Specifies the maximum difference between input and output timestamps.
+  // When specified, the mediapipe framework automatically computes output
+  // timestamp bounds based on input timestamps.  The special value
+  // TimestampDiff::Unset disables the timestamp offset.
+  void SetTimestampOffset(TimestampDiff offset) { timestamp_offset_ = offset; }
+  TimestampDiff GetTimestampOffset() const { return timestamp_offset_; }
+
   class GraphServiceRequest {
    public:
     // APIs that should be used by calculators.
@@ -147,6 +170,8 @@ class CalculatorContract {
   MediaPipeOptions input_stream_handler_options_;
   std::string node_name_;
   std::map<std::string, GraphServiceRequest> service_requests_;
+  bool process_timestamps_ = false;
+  TimestampDiff timestamp_offset_ = TimestampDiff::Unset();
 };
 
 }  // namespace mediapipe

mediapipe/framework/calculator_graph.h

@@ -143,7 +143,7 @@ class CalculatorGraph {
       const std::string& graph_type = "",
       const Subgraph::SubgraphOptions* options = nullptr);
 
-  // Resturns the canonicalized CalculatorGraphConfig for this graph.
+  // Returns the canonicalized CalculatorGraphConfig for this graph.
   const CalculatorGraphConfig& Config() const {
     return validated_graph_->Config();
   }

mediapipe/framework/calculator_graph_bounds_test.cc

@@ -31,6 +31,17 @@ namespace {
 typedef std::function<::mediapipe::Status(CalculatorContext* cc)>
     CalculatorContextFunction;
 
+// Returns the contents of a set of Packets.
+// The contents must be copyable.
+template <typename T>
+std::vector<T> GetContents(const std::vector<Packet>& packets) {
+  std::vector<T> result;
+  for (Packet p : packets) {
+    result.push_back(p.Get<T>());
+  }
+  return result;
+}
+
 // A simple Semaphore for synchronizing test threads.
 class AtomicSemaphore {
  public:
@@ -671,9 +682,9 @@ REGISTER_CALCULATOR(BoundToPacketCalculator);
 
 // A Calculator that produces packets at timestamps beyond the input timestamp.
 class FuturePacketCalculator : public CalculatorBase {
+ public:
   static constexpr int64 kOutputFutureMicros = 3;
 
- public:
   static ::mediapipe::Status GetContract(CalculatorContract* cc) {
     cc->Inputs().Index(0).Set<int>();
     cc->Outputs().Index(0).Set<int>();
@@ -742,9 +753,8 @@ TEST(CalculatorGraphBoundsTest, OffsetBoundPropagation) {
   MP_ASSERT_OK(graph.WaitUntilDone());
 }
 
-// Shows that bounds changes alone do not invoke Process.
+// Shows that timestamp bounds changes alone do not invoke Process,
-// Note: Bounds changes alone will invoke Process eventually
+// without SetProcessTimestampBounds(true).
-// when SetOffset is cleared, see: go/mediapipe-realtime-graph.
 TEST(CalculatorGraphBoundsTest, BoundWithoutInputPackets) {
   // OffsetBoundCalculator produces only timestamp bounds.
   // The BoundToPacketCalculator delivers an output packet whenever the
@@ -753,8 +763,13 @@ TEST(CalculatorGraphBoundsTest, BoundWithoutInputPackets) {
       ::mediapipe::ParseTextProtoOrDie<CalculatorGraphConfig>(R"(
         input_stream: 'input'
         node {
-          calculator: 'OffsetBoundCalculator'
+          calculator: 'FuturePacketCalculator'
           input_stream: 'input'
+          output_stream: 'input_2'
+        }
+        node {
+          calculator: 'OffsetBoundCalculator'
+          input_stream: 'input_2'
           output_stream: 'bounds'
         }
         node {
@@ -778,6 +793,7 @@ TEST(CalculatorGraphBoundsTest, BoundWithoutInputPackets) {
   for (int i = 0; i < kNumInputs; ++i) {
     Packet p = MakePacket<int>(33).At(Timestamp(i));
     MP_ASSERT_OK(graph.AddPacketToInputStream("input", p));
+    MP_ASSERT_OK(graph.WaitUntilIdle());
   }
 
   // No packets arrive, because updated timestamp bounds do not invoke
@@ -1104,5 +1120,254 @@ TEST(CalculatorGraphBoundsTest, BoundsForEmptyInputs_SyncSets) {
     )");
 }
 
+// A Calculator that produces a packet for each timestamp bounds update.
+class ProcessBoundToPacketCalculator : public CalculatorBase {
+ public:
+  static ::mediapipe::Status GetContract(CalculatorContract* cc) {
+    for (int i = 0; i < cc->Inputs().NumEntries(); ++i) {
+      cc->Inputs().Index(i).SetAny();
+    }
+    for (int i = 0; i < cc->Outputs().NumEntries(); ++i) {
+      cc->Outputs().Index(i).Set<Timestamp>();
+    }
+    cc->SetInputStreamHandler("ImmediateInputStreamHandler");
+    cc->SetProcessTimestampBounds(true);
+    return ::mediapipe::OkStatus();
+  }
+
+  ::mediapipe::Status Process(CalculatorContext* cc) final {
+    for (int i = 0; i < cc->Outputs().NumEntries(); ++i) {
+      Timestamp t = cc->Inputs().Index(i).Value().Timestamp();
+      if (t == cc->InputTimestamp() &&
+          t >= cc->Outputs().Index(i).NextTimestampBound()) {
+        cc->Outputs().Index(i).Add(new auto(t), t);
+      }
+    }
+    return ::mediapipe::OkStatus();
+  }
+};
+REGISTER_CALCULATOR(ProcessBoundToPacketCalculator);
+
+// A Calculator that passes through each packet and timestamp immediately.
+class ImmediatePassthroughCalculator : public CalculatorBase {
+ public:
+  static ::mediapipe::Status GetContract(CalculatorContract* cc) {
+    for (int i = 0; i < cc->Inputs().NumEntries(); ++i) {
+      cc->Inputs().Index(i).SetAny();
+    }
+    for (int i = 0; i < cc->Outputs().NumEntries(); ++i) {
+      cc->Outputs().Index(i).SetSameAs(&cc->Inputs().Index(i));
+    }
+    cc->SetInputStreamHandler("ImmediateInputStreamHandler");
+    cc->SetProcessTimestampBounds(true);
+    return ::mediapipe::OkStatus();
+  }
+
+  ::mediapipe::Status Process(CalculatorContext* cc) final {
+    for (int i = 0; i < cc->Outputs().NumEntries(); ++i) {
+      if (!cc->Inputs().Index(i).IsEmpty()) {
+        cc->Outputs().Index(i).AddPacket(cc->Inputs().Index(i).Value());
+      } else {
+        Timestamp input_bound =
+            cc->Inputs().Index(i).Value().Timestamp().NextAllowedInStream();
+        if (cc->Outputs().Index(i).NextTimestampBound() < input_bound) {
+          cc->Outputs().Index(i).SetNextTimestampBound(input_bound);
+        }
+      }
+    }
+    return ::mediapipe::OkStatus();
+  }
+};
+REGISTER_CALCULATOR(ImmediatePassthroughCalculator);
+
+// Shows that Process is called for input-sets without input packets.
+void TestProcessForEmptyInputs(const std::string& input_stream_handler) {
+  // FuturePacketCalculator and OffsetBoundCalculator produce only ts bounds,
+  // The ProcessBoundToPacketCalculator has SetProcessTimestampBounds(true),
+  // and produces an output packet for every timestamp bound update.
+  std::string config_str = R"(
+            input_stream: 'input'
+            node {
+              calculator: 'FuturePacketCalculator'
+              input_stream: 'input'
+              output_stream: 'futures'
+            }
+            node {
+              calculator: 'OffsetBoundCalculator'
+              input_stream: 'futures'
+              output_stream: 'bounds'
+            }
+            node {
+              calculator: 'ProcessBoundToPacketCalculator'
+              input_stream: 'bounds'
+              output_stream: 'bounds_ts'
+              input_stream_handler { $input_stream_handler }
+            }
+          )";
+  absl::StrReplaceAll({{"$input_stream_handler", input_stream_handler}},
+                      &config_str);
+  CalculatorGraphConfig config =
+      ::mediapipe::ParseTextProtoOrDie<CalculatorGraphConfig>(config_str);
+  CalculatorGraph graph;
+  std::vector<Packet> input_ts_packets;
+  std::vector<Packet> bounds_ts_packets;
+  MP_ASSERT_OK(graph.Initialize(config));
+  MP_ASSERT_OK(graph.ObserveOutputStream("bounds_ts", [&](const Packet& p) {
+    bounds_ts_packets.push_back(p);
+    return ::mediapipe::OkStatus();
+  }));
+  MP_ASSERT_OK(graph.StartRun({}));
+  MP_ASSERT_OK(graph.WaitUntilIdle());
+
+  // Add four packets into the graph.
+  constexpr int kFutureMicros = FuturePacketCalculator::kOutputFutureMicros;
+  Packet p;
+  p = MakePacket<int>(33).At(Timestamp(0));
+  MP_ASSERT_OK(graph.AddPacketToInputStream("input", p));
+  MP_ASSERT_OK(graph.WaitUntilIdle());
+
+  p = MakePacket<int>(33).At(Timestamp(10));
+  MP_ASSERT_OK(graph.AddPacketToInputStream("input", p));
+  MP_ASSERT_OK(graph.WaitUntilIdle());
+
+  p = MakePacket<int>(33).At(Timestamp(20));
+  MP_ASSERT_OK(graph.AddPacketToInputStream("input", p));
+  MP_ASSERT_OK(graph.WaitUntilIdle());
+
+  p = MakePacket<int>(33).At(Timestamp(30));
+  MP_ASSERT_OK(graph.AddPacketToInputStream("input", p));
+  MP_ASSERT_OK(graph.WaitUntilIdle());
+
+  // Packets arrive.
+  MP_ASSERT_OK(graph.WaitUntilIdle());
+  EXPECT_EQ(bounds_ts_packets.size(), 4);
+
+  std::vector<Timestamp> expected = {
+      Timestamp(0 + kFutureMicros), Timestamp(10 + kFutureMicros),
+      Timestamp(20 + kFutureMicros), Timestamp(30 + kFutureMicros)};
+  EXPECT_EQ(GetContents<Timestamp>(bounds_ts_packets), expected);
+
+  // Shutdown the graph.
+  MP_ASSERT_OK(graph.CloseAllPacketSources());
+  MP_ASSERT_OK(graph.WaitUntilDone());
+}
+
+// Shows that Process is called for input-sets without input packets
+// using an DefaultInputStreamHandler.
+TEST(CalculatorGraphBoundsTest, ProcessTimestampBounds_Default) {
+  TestProcessForEmptyInputs(R"(
+      input_stream_handler: "DefaultInputStreamHandler")");
+}
+
+// Shows that Process is called for input-sets without input packets
+// using an ImmediateInputStreamHandler.
+TEST(CalculatorGraphBoundsTest, ProcessTimestampBounds_Immediate) {
+  TestProcessForEmptyInputs(R"(
+      input_stream_handler: "ImmediateInputStreamHandler")");
+}
+
+// Shows that Process is called for input-sets without input packets
+// using a SyncSetInputStreamHandler with a single sync-set.
+TEST(CalculatorGraphBoundsTest, ProcessTimestampBounds_SyncSet) {
+  TestProcessForEmptyInputs(R"(
+      input_stream_handler: "SyncSetInputStreamHandler")");
+}
+
+// Shows that Process is called for input-sets without input packets
+// using a SyncSetInputStreamHandler with multiple sync-sets.
+TEST(CalculatorGraphBoundsTest, ProcessTimestampBounds_SyncSets) {
+  TestProcessForEmptyInputs(R"(
+      input_stream_handler: "SyncSetInputStreamHandler"
+      options {
+        [mediapipe.SyncSetInputStreamHandlerOptions.ext] {
+          sync_set { tag_index: ":0" }
+        }
+      }
+    )");
+}
+
+// Demonstrates the functionality of an "ImmediatePassthroughCalculator".
+// The ImmediatePassthroughCalculator simply relays each input packet to
+// the corresponding output stream.  ProcessTimestampBounds is needed to
+// relay timestamp bounds as well as packets.
+TEST(CalculatorGraphBoundsTest, ProcessTimestampBounds_Passthrough) {
+  // OffsetBoundCalculator produces timestamp bounds.
+  // ImmediatePassthroughCalculator relays packets and bounds.
+  // ProcessBoundToPacketCalculator reports packets and bounds as packets.
+  std::string config_str = R"(
+            input_stream: "input_0"
+            input_stream: "input_1"
+            node {
+              calculator: "OffsetBoundCalculator"
+              input_stream: "input_1"
+              output_stream: "bound_1"
+            }
+            node {
+              calculator: "ImmediatePassthroughCalculator"
+              input_stream: "input_0"
+              input_stream: "bound_1"
+              output_stream: "same_0"
+              output_stream: "same_1"
+            }
+            node {
+              calculator: "ProcessBoundToPacketCalculator"
+              input_stream: "same_0"
+              input_stream: "same_1"
+              output_stream: "output_0"
+              output_stream: "output_1"
+            }
+          )";
+  CalculatorGraphConfig config =
+      ::mediapipe::ParseTextProtoOrDie<CalculatorGraphConfig>(config_str);
+  CalculatorGraph graph;
+  std::vector<Packet> output_0_packets;
+  std::vector<Packet> output_1_packets;
+  MP_ASSERT_OK(graph.Initialize(config));
+  MP_ASSERT_OK(graph.ObserveOutputStream("output_0", [&](const Packet& p) {
+    output_0_packets.push_back(p);
+    return ::mediapipe::OkStatus();
+  }));
+  MP_ASSERT_OK(graph.ObserveOutputStream("output_1", [&](const Packet& p) {
+    output_1_packets.push_back(p);
+    return ::mediapipe::OkStatus();
+  }));
+  MP_ASSERT_OK(graph.StartRun({}));
+  MP_ASSERT_OK(graph.WaitUntilIdle());
+
+  // Add four packets to input_0.
+  for (int i = 0; i < 4; ++i) {
+    Packet p = MakePacket<int>(33).At(Timestamp(i * 10));
+    MP_ASSERT_OK(graph.AddPacketToInputStream("input_0", p));
+    MP_ASSERT_OK(graph.WaitUntilIdle());
+  }
+
+  // Packets arrive.
+  MP_ASSERT_OK(graph.WaitUntilIdle());
+  EXPECT_EQ(output_0_packets.size(), 4);
+  EXPECT_EQ(output_1_packets.size(), 0);
+  std::vector<Timestamp> expected =  //
+      {Timestamp(0), Timestamp(10), Timestamp(20), Timestamp(30)};
+  EXPECT_EQ(GetContents<Timestamp>(output_0_packets), expected);
+
+  // Add two timestamp bounds to bound_1.
+  for (int i = 0; i < 2; ++i) {
+    Packet p = MakePacket<int>(33).At(Timestamp(10 + i * 10));
+    MP_ASSERT_OK(graph.AddPacketToInputStream("input_1", p));
+    MP_ASSERT_OK(graph.WaitUntilIdle());
+  }
+
+  // Bounds arrive.
+  MP_ASSERT_OK(graph.WaitUntilIdle());
+  EXPECT_EQ(output_0_packets.size(), 4);
+  EXPECT_EQ(output_1_packets.size(), 2);
+  expected =  //
+      {Timestamp(10), Timestamp(20)};
+  EXPECT_EQ(GetContents<Timestamp>(output_1_packets), expected);
+
+  // Shutdown the graph.
+  MP_ASSERT_OK(graph.CloseAllPacketSources());
+  MP_ASSERT_OK(graph.WaitUntilDone());
+}
+
 }  // namespace
 }  // namespace mediapipe

mediapipe/framework/calculator_node.cc

@@ -97,6 +97,7 @@ Timestamp CalculatorNode::SourceProcessOrder(
 
   const NodeTypeInfo& node_type_info =
       validated_graph_->CalculatorInfos()[node_id_];
+  const CalculatorContract& contract = node_type_info.Contract();
 
   uses_gpu_ =
       node_type_info.InputSidePacketTypes().HasTag(kGpuSharedTagName) ||
@@ -147,6 +148,14 @@ Timestamp CalculatorNode::SourceProcessOrder(
       use_calc_specified ? handler_config : node_config.input_stream_handler(),
       node_type_info.InputStreamTypes()));
 
+  for (auto& stream : output_stream_handler_->OutputStreams()) {
+    stream->Spec()->offset_enabled =
+        (contract.GetTimestampOffset() != TimestampDiff::Unset());
+    stream->Spec()->offset = contract.GetTimestampOffset();
+  }
+  input_stream_handler_->SetProcessTimestampBounds(
+      contract.GetProcessTimestampBounds());
+
   return InitializeInputStreams(input_stream_managers, output_stream_managers);
 }
 

mediapipe/framework/deps/registration.cc

@@ -18,6 +18,10 @@ namespace mediapipe {
 
 namespace {
 
+// List of namespaces that can register calculators inside the namespace
+// and still refer to them using an unqualified name.  This whitelist
+// is meant to facilitate migration from unqualified to fully qualified
+// calculator names.
 constexpr char const* kTopNamespaces[] = {
     "mediapipe",
 };

mediapipe/framework/formats/annotation/BUILD

@@ -49,3 +49,10 @@ mediapipe_cc_proto_library(
     visibility = ["//visibility:public"],
     deps = [":rasterization_proto"],
 )
+
+# Expose the proto source files for building mediapipe AAR.
+filegroup(
+    name = "protos_src",
+    srcs = glob(["*.proto"]),
+    visibility = ["//mediapipe:__subpackages__"],
+)

mediapipe/framework/formats/annotation/rasterization.proto

@@ -16,6 +16,9 @@ syntax = "proto2";
 
 package mediapipe;
 
+option java_package = "com.google.mediapipe.formats.annotation.proto";
+option java_outer_classname = "RasterizationProto";
+
 // A Region can be represented in each frame as a set of scanlines
 // (compressed RLE, similar to rasterization of polygons).
 // For each scanline with y-coordinate y, we save (possibly multiple) intervals

mediapipe/framework/formats/location_data.proto

@@ -23,6 +23,9 @@ package mediapipe;
 
 import "mediapipe/framework/formats/annotation/rasterization.proto";
 
+option java_package = "com.google.mediapipe.formats.proto";
+option java_outer_classname = "LocationDataProto";
+
 message LocationData {
   // The supported formats for representing location data. A single location
   // must store its data in exactly one way.

mediapipe/framework/input_stream_handler.cc

@@ -22,6 +22,8 @@
 
 namespace mediapipe {
 
+using SyncSet = InputStreamHandler::SyncSet;
+
 ::mediapipe::Status InputStreamHandler::InitializeInputStreamManagers(
     InputStreamManager* flat_input_stream_managers) {
   for (CollectionItemId id = input_stream_managers_.BeginId();
@@ -300,4 +302,92 @@ void InputStreamHandler::SetLatePreparation(bool late_preparation) {
   late_preparation_ = late_preparation;
 }
 
+SyncSet::SyncSet(InputStreamHandler* input_stream_handler,
+                 std::vector<CollectionItemId> stream_ids)
+    : input_stream_handler_(input_stream_handler),
+      stream_ids_(std::move(stream_ids)) {}
+
+NodeReadiness SyncSet::GetReadiness(Timestamp* min_stream_timestamp) {
+  Timestamp min_bound = Timestamp::Done();
+  Timestamp min_packet = Timestamp::Done();
+  for (CollectionItemId id : stream_ids_) {
+    const auto& stream = input_stream_handler_->input_stream_managers_.Get(id);
+    bool empty;
+    Timestamp stream_timestamp = stream->MinTimestampOrBound(&empty);
+    if (empty) {
+      min_bound = std::min(min_bound, stream_timestamp);
+    } else {
+      min_packet = std::min(min_packet, stream_timestamp);
+    }
+  }
+  *min_stream_timestamp = std::min(min_packet, min_bound);
+  if (*min_stream_timestamp == Timestamp::Done()) {
+    last_processed_ts_ = Timestamp::Done().PreviousAllowedInStream();
+    return NodeReadiness::kReadyForClose;
+  }
+  if (!input_stream_handler_->process_timestamps_) {
+    // Only an input_ts with packets can be processed.
+    // Note that (min_bound - 1) is the highest fully settled timestamp.
+    if (min_bound > min_packet) {
+      last_processed_ts_ = *min_stream_timestamp;
+      return NodeReadiness::kReadyForProcess;
+    }
+  } else {
+    // Any unprocessed input_ts can be processed.
+    // Note that (min_bound - 1) is the highest fully settled timestamp.
+    Timestamp input_timestamp =
+        std::min(min_packet, min_bound.PreviousAllowedInStream());
+    if (input_timestamp >
+        std::max(last_processed_ts_, Timestamp::Unstarted())) {
+      *min_stream_timestamp = input_timestamp;
+      last_processed_ts_ = input_timestamp;
+      return NodeReadiness::kReadyForProcess;
+    }
+  }
+  return NodeReadiness::kNotReady;
+}
+
+Timestamp SyncSet::LastProcessed() const { return last_processed_ts_; }
+
+Timestamp SyncSet::MinPacketTimestamp() const {
+  Timestamp result = Timestamp::Done();
+  for (CollectionItemId id : stream_ids_) {
+    const auto& stream = input_stream_handler_->input_stream_managers_.Get(id);
+    bool empty;
+    Timestamp stream_timestamp = stream->MinTimestampOrBound(&empty);
+    if (!empty) {
+      result = std::min(result, stream_timestamp);
+    }
+  }
+  return result;
+}
+
+void SyncSet::FillInputSet(Timestamp input_timestamp,
+                           InputStreamShardSet* input_set) {
+  CHECK(input_timestamp.IsAllowedInStream());
+  CHECK(input_set);
+  for (CollectionItemId id : stream_ids_) {
+    const auto& stream = input_stream_handler_->input_stream_managers_.Get(id);
+    int num_packets_dropped = 0;
+    bool stream_is_done = false;
+    Packet current_packet = stream->PopPacketAtTimestamp(
+        input_timestamp, &num_packets_dropped, &stream_is_done);
+    CHECK_EQ(num_packets_dropped, 0)
+        << absl::Substitute("Dropped $0 packet(s) on input stream \"$1\".",
+                            num_packets_dropped, stream->Name());
+    input_stream_handler_->AddPacketToShard(
+        &input_set->Get(id), std::move(current_packet), stream_is_done);
+  }
+}
+
+void SyncSet::FillInputBounds(InputStreamShardSet* input_set) {
+  for (CollectionItemId id : stream_ids_) {
+    const auto* stream = input_stream_handler_->input_stream_managers_.Get(id);
+    Timestamp bound = stream->MinTimestampOrBound(nullptr);
+    input_stream_handler_->AddPacketToShard(
+        &input_set->Get(id), Packet().At(bound.PreviousAllowedInStream()),
+        bound == Timestamp::Done());
+  }
+}
+
 }  // namespace mediapipe

mediapipe/framework/input_stream_handler.h

@@ -74,9 +74,7 @@ class InputStreamHandler {
       : input_stream_managers_(std::move(tag_map)),
         calculator_context_manager_(calculator_context_manager),
         options_(options),
-        calculator_run_in_parallel_(calculator_run_in_parallel),
+        calculator_run_in_parallel_(calculator_run_in_parallel) {}
-        late_preparation_(false),
-        batch_size_(1) {}
 
   virtual ~InputStreamHandler() = default;
 
@@ -174,6 +172,57 @@ class InputStreamHandler {
     return unset_header_count_.load(std::memory_order_relaxed);
   }
 
+  // When true, Calculator::Process is called for any increase in the
+  // timestamp bound, whether or not any packets are available.
+  // Calculator::Process is called when the minimum timestamp bound
+  // increases for any synchronized set of input streams.
+  // DefaultInputStreamHandler groups all input streams into a single set.
+  // ImmediateInputStreamHandler treats each input stream as a separate set.
+  void SetProcessTimestampBounds(bool process_ts) {
+    process_timestamps_ = process_ts;
+  }
+
+  // When true, Calculator::Process is called for every input timestamp bound.
+  bool ProcessTimestampBounds() { return process_timestamps_; }
+
+  // A helper class to build input packet sets for a certain set of streams.
+  //
+  // ReadyForProcess requires all of the streams to be fully determined
+  // at the same input-timestamp.
+  // This is the readiness policy for all streams in DefaultInputStreamHandler.
+  // It is also the policy for each sync-set in SyncSetInputStreamHandler.
+  // It is also the policy for each input-stream in ImmediateInputStreamHandler.
+  //
+  // If ProcessTimestampBounds() is set, then a fully determined input timestamp
+  // with only empty input packets will qualify as ReadyForProcess.
+  class SyncSet {
+   public:
+    // Creates a SyncSet for a certain set of streams, |stream_ids|.
+    SyncSet(InputStreamHandler* input_stream_handler,
+            std::vector<CollectionItemId> stream_ids);
+
+    // Answers whether this stream is ready for Process or Close.
+    NodeReadiness GetReadiness(Timestamp* min_stream_timestamp);
+
+    // Returns the latest timestamp returned for processing.
+    Timestamp LastProcessed() const;
+
+    // The earliest available packet timestamp, or Timestamp::Done.
+    Timestamp MinPacketTimestamp() const;
+
+    // Moves packets from all input streams to the input_set.
+    void FillInputSet(Timestamp input_timestamp,
+                      InputStreamShardSet* input_set);
+
+    // Copies timestamp bounds from all input streams to the input_set.
+    void FillInputBounds(InputStreamShardSet* input_set);
+
+   private:
+    InputStreamHandler* input_stream_handler_;
+    std::vector<CollectionItemId> stream_ids_;
+    Timestamp last_processed_ts_ = Timestamp::Unset();
+  };
+
  protected:
   typedef internal::Collection<InputStreamManager*> InputStreamManagerSet;
 
@@ -240,11 +289,14 @@ class InputStreamHandler {
   // The variable is set to false by default. A subclass should set it to true
   // with SetLatePreparation(true) in the constructor if the input sets need to
   // be filled in ProcessNode().
-  bool late_preparation_;
+  bool late_preparation_ = false;
 
   // Determines how many sets of input packets are collected before a
   // CalculatorNode is scheduled.
-  int batch_size_;
+  int batch_size_ = 1;
+
+  // When true, any increase in timestamp bound invokes Calculator::Process.
+  bool process_timestamps_ = false;
 
   // A callback to notify the observer when all the input stream headers
   // (excluding headers of back edges) become available.

mediapipe/framework/legacy_calculator_support.h

@@ -107,6 +107,9 @@ CalculatorContext* LegacyCalculatorSupport::Scoped<CalculatorContext>::current_;
 template <>
 CalculatorContract*
     LegacyCalculatorSupport::Scoped<CalculatorContract>::current_;
+#elif _MSC_VER
+// MSVC interprets these declarations as definitions and during linking it
+// generates an error about multiple definitions of current_.
 #else
 template <>
 thread_local CalculatorContext*

mediapipe/framework/output_stream_handler.h

@@ -46,6 +46,7 @@ class OutputStreamHandler {
   // ids of upstream sources that affect it.
   typedef std::unordered_map<std::string, std::unordered_set<int>>
       OutputStreamToSourcesMap;
+  typedef internal::Collection<OutputStreamManager*> OutputStreamManagerSet;
 
   // The constructor of the OutputStreamHandler takes four arguments.
   // The tag_map argument holds the information needed for tag/index retrieval
@@ -119,9 +120,11 @@ class OutputStreamHandler {
   // collection for debugging purpose.
   std::string FirstStreamName() const;
 
- protected:
+  const OutputStreamManagerSet& OutputStreams() {
-  typedef internal::Collection<OutputStreamManager*> OutputStreamManagerSet;
+    return output_stream_managers_;
+  }
 
+ protected:
   // Checks if the given input bound should be propagated or not. If any output
   // streams with OffsetEnabled() need to have the timestamp bounds updated,
   // then propagates the timestamp bounds of all output streams with

mediapipe/framework/output_stream_poller.h

@@ -27,6 +27,9 @@ class OutputStreamPoller {
   OutputStreamPoller(const OutputStreamPoller&) = delete;
   OutputStreamPoller& operator=(const OutputStreamPoller&) = delete;
   OutputStreamPoller(OutputStreamPoller&&) = default;
+  // Move assignment needs to be explicitly defaulted to allow ASSIGN_OR_RETURN
+  // on `StatusOr<OutputStreamPoller>`.
+  OutputStreamPoller& operator=(OutputStreamPoller&&) = default;
 
   // Resets OutputStramPollerImpl and cleans the internal packet queue.
   void Reset() {

mediapipe/framework/profiler/testdata/profile_latency_test.pbtxt

@@ -0,0 +1,97 @@
+graph_trace: {
+    calculator_name : ["ACalculator", "BCalculator"]
+    stream_name     : [ "", "input1", "a_b"]
+    base_time       : 0
+    base_timestamp  : 100
+
+    # Fire off three input packets and have them spend time in Calculator A.
+    # Drop the middle packet.
+
+    calculator_trace: {
+      node_id: -1
+      input_timestamp: 100
+      event_type     : PROCESS
+      finish_time    : 1000
+      output_trace: {
+        packet_timestamp: 100
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+    calculator_trace: {
+      node_id: -1
+      input_timestamp: 101
+      event_type     : PROCESS
+      finish_time    : 2000
+      output_trace: {
+        packet_timestamp: 101
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+
+    calculator_trace: {
+      node_id: 0
+      input_timestamp: 100
+      event_type     : PROCESS
+      start_time     : 1200  # 200 after initial input (emits at 1000)
+      finish_time    : 1500  # Speed to delivery is 500 (1500 - 1000)
+      input_trace: {
+        packet_timestamp: 100
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+
+    calculator_trace: {
+      node_id: 0
+      input_timestamp: 101
+      event_type     : PROCESS
+      start_time     : 2100  # 100 after initial input (emits at 2000)
+      finish_time    : 2500  # Speed to delivery is 500 (2500 - 2000)
+      input_trace: {
+        packet_timestamp: 101
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+
+    calculator_trace: {
+      node_id: 1
+      input_timestamp: 100
+      event_type     : PROCESS
+      start_time     : 1600  # 600 after the initial input (emits at 1000)
+      finish_time    : 2000  # Speed to delivery is 1000 (2000 - 1000)
+      input_trace: {
+        packet_timestamp: 100
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+
+    calculator_trace: {
+      node_id: 1
+      input_timestamp: 101
+      event_type     : PROCESS
+      start_time     : 2900  # 700 after the initial input (emits at 2000)
+      finish_time    : 3100  # Speed to delivery is 1000 (3000 - 2000)
+      input_trace: {
+        packet_timestamp: 101
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+}
+config: {
+  node: {
+    name: "ACalculator"
+    calculator: "ACalculator"
+    input_stream: "input1"
+    output_stream: "a_b"
+  }
+  node: {
+    name: "BCalculator"
+    calculator: "BCalculator"
+    input_stream: "a_b"
+  }
+}

mediapipe/framework/profiler/testdata/profile_process_test.pbtxt

@@ -0,0 +1,122 @@
+graph_trace: {
+    calculator_name : ["ACalculator", "BCalculator"]
+    stream_name     : [ "", "input1"]
+    base_time       : 0
+    base_timestamp  : 100
+
+    # Fire off three input packets and have them spend time in Calculator A.
+    # Drop the middle packet.
+
+    calculator_trace: {
+      node_id: -1
+      input_timestamp: 100
+      event_type     : PROCESS
+      finish_time    : 1000
+      output_trace: {
+        packet_timestamp: 100
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+    calculator_trace: {
+      node_id: -1
+      input_timestamp: 101
+      event_type     : PROCESS
+      finish_time    : 2000
+      output_trace: {
+        packet_timestamp: 101
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+    calculator_trace: {
+      node_id: -1
+      input_timestamp: 102
+      event_type     : PROCESS
+      finish_time    : 3000
+      output_trace: {
+        packet_timestamp: 102
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+
+    # First event is disconnected. We'll see the output_trace later.
+    calculator_trace: {
+      node_id: 0
+      input_timestamp: 100
+      event_type     : PROCESS
+      start_time    : 1100
+      input_trace: {
+        packet_timestamp: 100
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+
+    # # We're going to drop this packet.
+    calculator_trace: {
+      node_id: 0
+      input_timestamp: 101
+      event_type     : PROCESS
+      start_time     : 2100
+      input_trace: {
+        packet_timestamp: 101
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+    # # Here's that matching output trace.
+    calculator_trace: {
+      node_id: 0
+      input_timestamp: 100
+      event_type     : PROCESS
+      finish_time    : 1500
+      input_trace: {
+        packet_timestamp: 100
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+    # Third packet is processed all at the same time.
+    calculator_trace: {
+      node_id: 0
+      input_timestamp: 102
+      event_type     : PROCESS
+      start_time     : 3100
+      finish_time    : 3600
+      input_trace: {
+        packet_timestamp: 102
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+
+    # A second calculator will process an input in order to affect the
+    # time_percent.
+
+    calculator_trace: {
+      node_id: 1
+      input_timestamp: 102
+      event_type     : PROCESS
+      start_time     : 3200
+      finish_time    : 3500
+      input_trace: {
+        packet_timestamp: 102
+        stream_id       : 1
+      }
+      thread_id      : 1
+    }
+}
+config: {
+  node: {
+    name: "ACalculator"
+    calculator: "ACalculator"
+    input_stream: "input1"
+  }
+  node: {
+    name: "BCalculator"
+    calculator: "BCalculator"
+    input_stream: "input1"
+  }
+}

mediapipe/framework/scheduler_queue.cc

@@ -25,7 +25,11 @@
 #include "mediapipe/framework/port/logging.h"
 #include "mediapipe/framework/port/status.h"
 
+#ifdef __APPLE__
+#define AUTORELEASEPOOL @autoreleasepool
+#else
 #define AUTORELEASEPOOL
+#endif  // __APPLE__
 
 namespace mediapipe {
 namespace internal {

mediapipe/framework/stream_handler/default_input_stream_handler.cc

@@ -17,16 +17,28 @@
 #include <algorithm>
 
 #include "absl/strings/substitute.h"
+#include "mediapipe/framework/input_stream_handler.h"
 
 namespace mediapipe {
 
 REGISTER_INPUT_STREAM_HANDLER(DefaultInputStreamHandler);
 
+// Returns all CollectionItemId's for a Collection TagMap.
+std::vector<CollectionItemId> GetIds(
+    const std::shared_ptr<tool::TagMap>& tag_map) {
+  std::vector<CollectionItemId> result;
+  for (auto id = tag_map->BeginId(); id < tag_map->EndId(); ++id) {
+    result.push_back(id);
+  }
+  return result;
+}
+
 DefaultInputStreamHandler::DefaultInputStreamHandler(
     std::shared_ptr<tool::TagMap> tag_map, CalculatorContextManager* cc_manager,
     const MediaPipeOptions& options, bool calculator_run_in_parallel)
     : InputStreamHandler(std::move(tag_map), cc_manager, options,
-                         calculator_run_in_parallel) {
+                         calculator_run_in_parallel),
+      sync_set_(this, GetIds(input_stream_managers_.TagMap())) {
   if (options.HasExtension(DefaultInputStreamHandlerOptions::ext)) {
     SetBatchSize(options.GetExtension(DefaultInputStreamHandlerOptions::ext)
                      .batch_size());
@@ -35,47 +47,12 @@ DefaultInputStreamHandler::DefaultInputStreamHandler(
 
 NodeReadiness DefaultInputStreamHandler::GetNodeReadiness(
     Timestamp* min_stream_timestamp) {
-  DCHECK(min_stream_timestamp);
+  return sync_set_.GetReadiness(min_stream_timestamp);
-  *min_stream_timestamp = Timestamp::Done();
-  Timestamp min_bound = Timestamp::Done();
-  for (const auto& stream : input_stream_managers_) {
-    bool empty;
-    Timestamp stream_timestamp = stream->MinTimestampOrBound(&empty);
-    if (empty) {
-      min_bound = std::min(min_bound, stream_timestamp);
-    }
-    *min_stream_timestamp = std::min(*min_stream_timestamp, stream_timestamp);
-  }
-
-  if (*min_stream_timestamp == Timestamp::Done()) {
-    return NodeReadiness::kReadyForClose;
-  }
-
-  if (min_bound > *min_stream_timestamp) {
-    return NodeReadiness::kReadyForProcess;
-  }
-
-  CHECK_EQ(min_bound, *min_stream_timestamp);
-  return NodeReadiness::kNotReady;
 }
 
 void DefaultInputStreamHandler::FillInputSet(Timestamp input_timestamp,
                                              InputStreamShardSet* input_set) {
-  CHECK(input_timestamp.IsAllowedInStream());
+  sync_set_.FillInputSet(input_timestamp, input_set);
-  CHECK(input_set);
-  for (CollectionItemId id = input_stream_managers_.BeginId();
-       id < input_stream_managers_.EndId(); ++id) {
-    auto& stream = input_stream_managers_.Get(id);
-    int num_packets_dropped = 0;
-    bool stream_is_done = false;
-    Packet current_packet = stream->PopPacketAtTimestamp(
-        input_timestamp, &num_packets_dropped, &stream_is_done);
-    CHECK_EQ(num_packets_dropped, 0)
-        << absl::Substitute("Dropped $0 packet(s) on input stream \"$1\".",
-                            num_packets_dropped, stream->Name());
-    AddPacketToShard(&input_set->Get(id), std::move(current_packet),
-                     stream_is_done);
-  }
 }
 
 }  // namespace mediapipe

mediapipe/framework/stream_handler/default_input_stream_handler.h

@@ -45,6 +45,9 @@ class DefaultInputStreamHandler : public InputStreamHandler {
   // Only invoked when associated GetNodeReadiness() returned kReadyForProcess.
   void FillInputSet(Timestamp input_timestamp,
                     InputStreamShardSet* input_set) override;
+
+  // The packet-set builder.
+  SyncSet sync_set_;
 };
 
 }  // namespace mediapipe

mediapipe/framework/stream_handler/immediate_input_stream_handler.cc

@@ -19,6 +19,8 @@
 
 namespace mediapipe {
 
+using SyncSet = InputStreamHandler::SyncSet;
+
 // An input stream handler that delivers input packets to the Calculator
 // immediately, with no dependency between input streams.  It also invokes
 // Calculator::Process when any input stream becomes done.
@@ -47,8 +49,11 @@ class ImmediateInputStreamHandler : public InputStreamHandler {
   void FillInputSet(Timestamp input_timestamp,
                     InputStreamShardSet* input_set) override;
 
-  // Record of the last reported timestamp bound for each input stream.
+  absl::Mutex mutex_;
-  mediapipe::internal::Collection<Timestamp> timestamp_bounds_;
+  // The packet-set builder for each input stream.
+  std::vector<SyncSet> sync_sets_ ABSL_GUARDED_BY(mutex_);
+  // The input timestamp for each kReadyForProcess input stream.
+  std::vector<Timestamp> ready_timestamps_ ABSL_GUARDED_BY(mutex_);
 };
 REGISTER_INPUT_STREAM_HANDLER(ImmediateInputStreamHandler);
 
@@ -57,31 +62,47 @@ ImmediateInputStreamHandler::ImmediateInputStreamHandler(
     CalculatorContextManager* calculator_context_manager,
     const MediaPipeOptions& options, bool calculator_run_in_parallel)
     : InputStreamHandler(tag_map, calculator_context_manager, options,
-                         calculator_run_in_parallel),
+                         calculator_run_in_parallel) {
-      timestamp_bounds_(std::move(tag_map)) {}
+  for (auto id = tag_map->BeginId(); id < tag_map->EndId(); ++id) {
+    sync_sets_.emplace_back(this, std::vector<CollectionItemId>{id});
+    ready_timestamps_.push_back(Timestamp::Unset());
+  }
+}
 
 NodeReadiness ImmediateInputStreamHandler::GetNodeReadiness(
     Timestamp* min_stream_timestamp) {
-  *min_stream_timestamp = Timestamp::Done();
+  absl::MutexLock lock(&mutex_);
   Timestamp input_timestamp = Timestamp::Done();
+  Timestamp min_bound = Timestamp::Done();
   bool stream_became_done = false;
-
+  for (int i = 0; i < sync_sets_.size(); ++i) {
-  for (CollectionItemId i = input_stream_managers_.BeginId();
+    if (ready_timestamps_[i] > Timestamp::Unset()) {
-       i < input_stream_managers_.EndId(); ++i) {
+      min_bound = std::min(min_bound, ready_timestamps_[i]);
-    const auto& stream = input_stream_managers_.Get(i);
+      input_timestamp = std::min(input_timestamp, ready_timestamps_[i]);
-    bool empty;
+      continue;
-    Timestamp stream_timestamp = stream->MinTimestampOrBound(&empty);
-    if (!empty) {
-      input_timestamp = std::min(input_timestamp, stream_timestamp);
     }
-    *min_stream_timestamp = std::min(*min_stream_timestamp, stream_timestamp);
+    Timestamp prev_ts = sync_sets_[i].LastProcessed();
-    if (stream_timestamp != timestamp_bounds_.Get(i)) {
+    Timestamp stream_ts;
-      if (stream_timestamp == Timestamp::Done()) {
+    NodeReadiness readiness = sync_sets_[i].GetReadiness(&stream_ts);
+    min_bound = std::min(min_bound, stream_ts);
+    if (readiness == NodeReadiness::kReadyForProcess) {
+      ready_timestamps_[i] = stream_ts;
+      input_timestamp = std::min(input_timestamp, stream_ts);
+    } else if (readiness == NodeReadiness::kReadyForClose) {
+      CHECK_EQ(stream_ts, Timestamp::Done());
+      if (ProcessTimestampBounds()) {
+        // With kReadyForClose, the timestamp-bound Done is returned.
+        // This bound is processed using the preceding input-timestamp.
+        // TODO: Make all InputStreamHandlers process Done() like this.
+        ready_timestamps_[i] = stream_ts.PreviousAllowedInStream();
+        input_timestamp = std::min(input_timestamp, ready_timestamps_[i]);
+      } else if (prev_ts < Timestamp::Done()) {
         stream_became_done = true;
-      }
+        ready_timestamps_[i] = Timestamp::Done();
-      timestamp_bounds_.Get(i) = stream_timestamp;
       }
     }
+  }
+  *min_stream_timestamp = min_bound;
 
   if (*min_stream_timestamp == Timestamp::Done()) {
     return NodeReadiness::kReadyForClose;
@@ -94,6 +115,8 @@ NodeReadiness ImmediateInputStreamHandler::GetNodeReadiness(
   }
 
   if (stream_became_done) {
+    // The stream_became_done logic is kept for backward compatibility.
+    // Note that the minimum bound is returned in min_stream_timestamp.
     return NodeReadiness::kReadyForProcess;
   }
 
@@ -102,23 +125,13 @@ NodeReadiness ImmediateInputStreamHandler::GetNodeReadiness(
 
 void ImmediateInputStreamHandler::FillInputSet(Timestamp input_timestamp,
                                                InputStreamShardSet* input_set) {
-  CHECK(input_timestamp.IsAllowedInStream());
+  absl::MutexLock lock(&mutex_);
-  CHECK(input_set);
+  for (int i = 0; i < sync_sets_.size(); ++i) {
-  for (CollectionItemId id = input_stream_managers_.BeginId();
+    if (ready_timestamps_[i] == input_timestamp) {
-       id < input_stream_managers_.EndId(); ++id) {
+      sync_sets_[i].FillInputSet(input_timestamp, input_set);
-    auto& stream = input_stream_managers_.Get(id);
+      ready_timestamps_[i] = Timestamp::Unset();
-    if (stream->QueueHead().Timestamp() == input_timestamp) {
-      int num_packets_dropped = 0;
-      bool stream_is_done = false;
-      Packet current_packet = stream->PopPacketAtTimestamp(
-          input_timestamp, &num_packets_dropped, &stream_is_done);
-      AddPacketToShard(&input_set->Get(id), std::move(current_packet),
-                       stream_is_done);
     } else {
-      Timestamp bound = stream->MinTimestampOrBound(nullptr);
+      sync_sets_[i].FillInputBounds(input_set);
-      AddPacketToShard(&input_set->Get(id),
-                       Packet().At(bound.PreviousAllowedInStream()),
-                       bound == Timestamp::Done());
     }
   }
 }

mediapipe/framework/stream_handler/sync_set_input_stream_handler.cc

@@ -17,6 +17,7 @@
 // TODO: Move protos in another CL after the C++ code migration.
 #include "absl/strings/substitute.h"
 #include "absl/synchronization/mutex.h"
+#include "mediapipe/framework/collection_item_id.h"
 #include "mediapipe/framework/input_stream_handler.h"
 #include "mediapipe/framework/mediapipe_options.pb.h"
 #include "mediapipe/framework/packet_set.h"
@@ -69,7 +70,7 @@ class SyncSetInputStreamHandler : public InputStreamHandler {
  private:
   absl::Mutex mutex_;
   // The ids of each set of inputs.
-  std::vector<std::vector<CollectionItemId>> sync_sets_ ABSL_GUARDED_BY(mutex_);
+  std::vector<SyncSet> sync_sets_ ABSL_GUARDED_BY(mutex_);
   // The index of the ready sync set.  A value of -1 indicates that no
   // sync sets are ready.
   int ready_sync_set_index_ ABSL_GUARDED_BY(mutex_) = -1;
@@ -98,7 +99,7 @@ void SyncSetInputStreamHandler::PrepareForRun(
     sync_sets_.clear();
     std::set<CollectionItemId> used_ids;
     for (const auto& sync_set : handler_options.sync_set()) {
-      sync_sets_.emplace_back();
+      std::vector<CollectionItemId> stream_ids;
       CHECK_LT(0, sync_set.tag_index_size());
       for (const auto& tag_index : sync_set.tag_index()) {
         std::string tag;
@@ -109,8 +110,9 @@ void SyncSetInputStreamHandler::PrepareForRun(
         CHECK(!::mediapipe::ContainsKey(used_ids, id))
             << "stream \"" << tag_index << "\" is in more than one sync set.";
         used_ids.insert(id);
-        sync_sets_.back().push_back(id);
+        stream_ids.push_back(id);
       }
+      sync_sets_.emplace_back(this, std::move(stream_ids));
     }
     std::vector<CollectionItemId> remaining_ids;
     for (CollectionItemId id = input_stream_managers_.BeginId();
@@ -120,7 +122,7 @@ void SyncSetInputStreamHandler::PrepareForRun(
       }
     }
     if (!remaining_ids.empty()) {
-      sync_sets_.push_back(std::move(remaining_ids));
+      sync_sets_.emplace_back(this, std::move(remaining_ids));
     }
     ready_sync_set_index_ = -1;
     ready_timestamp_ = Timestamp::Done();
@@ -137,24 +139,14 @@ NodeReadiness SyncSetInputStreamHandler::GetNodeReadiness(
   absl::MutexLock lock(&mutex_);
   if (ready_sync_set_index_ >= 0) {
     *min_stream_timestamp = ready_timestamp_;
+    // TODO: Return kNotReady unless a new ready syncset is found.
     return NodeReadiness::kReadyForProcess;
   }
   for (int sync_set_index = 0; sync_set_index < sync_sets_.size();
        ++sync_set_index) {
-    const std::vector<CollectionItemId>& sync_set = sync_sets_[sync_set_index];
+    NodeReadiness readiness =
-    *min_stream_timestamp = Timestamp::Done();
+        sync_sets_[sync_set_index].GetReadiness(min_stream_timestamp);
-    Timestamp min_bound = Timestamp::Done();
+    if (readiness == NodeReadiness::kReadyForClose) {
-    for (CollectionItemId id : sync_set) {
-      const auto& stream = input_stream_managers_.Get(id);
-      bool empty;
-      Timestamp stream_timestamp = stream->MinTimestampOrBound(&empty);
-      if (empty) {
-        min_bound = std::min(min_bound, stream_timestamp);
-      }
-      *min_stream_timestamp = std::min(*min_stream_timestamp, stream_timestamp);
-    }
-
-    if (*min_stream_timestamp == Timestamp::Done()) {
       // This sync set is done, remove it.  Note that this invalidates
       // sync set indexes higher than sync_set_index.  However, we are
       // guaranteed that we were not ready before entering the outer
@@ -165,15 +157,14 @@ NodeReadiness SyncSetInputStreamHandler::GetNodeReadiness(
       continue;
     }
 
-    if (min_bound > *min_stream_timestamp) {
+    if (readiness == NodeReadiness::kReadyForProcess) {
+      // TODO: Prioritize sync-sets to avoid starvation.
       if (*min_stream_timestamp < ready_timestamp_) {
         // Store the timestamp and corresponding sync set index for the
         // sync set with the earliest arrival timestamp.
         ready_timestamp_ = *min_stream_timestamp;
         ready_sync_set_index_ = sync_set_index;
       }
-    } else {
-      CHECK_EQ(min_bound, *min_stream_timestamp);
     }
   }
   if (ready_sync_set_index_ >= 0) {
@@ -188,44 +179,17 @@ NodeReadiness SyncSetInputStreamHandler::GetNodeReadiness(
   return NodeReadiness::kNotReady;
 }
 
-void SyncSetInputStreamHandler::FillInputBounds(
-    Timestamp input_timestamp, InputStreamShardSet* input_set) {
-  for (int i = 0; i < sync_sets_.size(); ++i) {
-    if (i != ready_sync_set_index_) {
-      // Set the input streams for the not-ready sync sets.
-      for (CollectionItemId id : sync_sets_[i]) {
-        const auto stream = input_stream_managers_.Get(id);
-        Timestamp bound = stream->MinTimestampOrBound(nullptr);
-        AddPacketToShard(&input_set->Get(id),
-                         Packet().At(bound.PreviousAllowedInStream()),
-                         bound == Timestamp::Done());
-      }
-    }
-  }
-}
-
 void SyncSetInputStreamHandler::FillInputSet(Timestamp input_timestamp,
                                              InputStreamShardSet* input_set) {
   // Assume that all current packets are already cleared.
-  CHECK(input_timestamp.IsAllowedInStream());
-  CHECK(input_set);
   absl::MutexLock lock(&mutex_);
   CHECK_LE(0, ready_sync_set_index_);
-  CHECK_EQ(input_timestamp, ready_timestamp_);
+  sync_sets_[ready_sync_set_index_].FillInputSet(input_timestamp, input_set);
-  // Set the input streams for the ready sync set.
+  for (int i = 0; i < sync_sets_.size(); ++i) {
-  for (CollectionItemId id : sync_sets_[ready_sync_set_index_]) {
+    if (i != ready_sync_set_index_) {
-    const auto& stream = input_stream_managers_.Get(id);
+      sync_sets_[i].FillInputBounds(input_set);
-    int num_packets_dropped = 0;
+    }
-    bool stream_is_done = false;
-    Packet current_packet = stream->PopPacketAtTimestamp(
-        input_timestamp, &num_packets_dropped, &stream_is_done);
-    CHECK_EQ(num_packets_dropped, 0)
-        << absl::Substitute("Dropped $0 packet(s) on input stream \"$1\".",
-                            num_packets_dropped, stream->Name());
-    AddPacketToShard(&input_set->Get(id), std::move(current_packet),
-                     stream_is_done);
   }
-  FillInputBounds(input_timestamp, input_set);
   ready_sync_set_index_ = -1;
   ready_timestamp_ = Timestamp::Done();
 }

mediapipe/framework/timestamp.cc

@@ -122,7 +122,6 @@ std::string TimestampDiff::DebugString() const {
 }
 
 Timestamp Timestamp::NextAllowedInStream() const {
-  CHECK(IsAllowedInStream()) << "Timestamp is: " << DebugString();
   if (*this >= Max() || *this == PreStream()) {
     // Indicates that no further timestamps may occur.
     return OneOverPostStream();

mediapipe/framework/timestamp.h

@@ -247,6 +247,12 @@ class TimestampDiff {
   TimestampDiff operator-(const TimestampDiff other) const;
   Timestamp operator+(const Timestamp other) const;
 
+  // Special values.
+
+  static TimestampDiff Unset() {
+    return TimestampDiff(Timestamp::Unset().Value());
+  }
+
  private:
   TimestampBaseType timestamp_;
 };

mediapipe/framework/validated_graph_config.cc

@@ -815,16 +815,25 @@ NodeTypeInfo::NodeRef ValidatedGraphConfig::NodeForSorterIndex(
       sorted_nodes_.push_back(&tmp_calculators.back());
     }
   }
+  if (cyclic) {
+    // This reads from partilly altered config_ (by node Swap()) but we assume
+    // the nodes in the cycle are not altered, as TopologicalSorter reports
+    // cyclicity before processing any node in cycle.
+    auto node_name_formatter = [this](std::string* out, int i) {
+      const auto& n = NodeForSorterIndex(i);
+      absl::StrAppend(out, n.type == NodeTypeInfo::NodeType::CALCULATOR
+                               ? tool::CanonicalNodeName(Config(), n.index)
+                               : DebugName(Config(), n.type, n.index));
+    };
+    return ::mediapipe::UnknownErrorBuilder(MEDIAPIPE_LOC)
+           << "Generator side packet cycle or calculator stream cycle detected "
+              "in graph: ["
+           << absl::StrJoin(cycle_indexes, ", ", node_name_formatter) << "]";
+  }
   generator_configs.Swap(config_.mutable_packet_generator());
   tmp_generators.swap(generators_);
   node_configs.Swap(config_.mutable_node());
   tmp_calculators.swap(calculators_);
-  if (cyclic) {
-    return ::mediapipe::UnknownErrorBuilder(MEDIAPIPE_LOC)
-           << "Generator side packet cycle or calculator stream cycle detected "
-              "in graph.  Cycle indexes: "
-           << absl::StrJoin(cycle_indexes, ", ");
-  }
 #if !(defined(MEDIAPIPE_LITE) || defined(MEDIAPIPE_MOBILE))
   VLOG(2) << "AFTER TOPOLOGICAL SORT:\n" << config_.DebugString();
 #endif  // !(MEDIAPIPE_LITE || MEDIAPIPE_MOBILE)

mediapipe/gpu/gl_base.h

@@ -57,15 +57,14 @@
 #include <EGL/egl.h>
 #include <GLES2/gl2.h>
 #include <GLES2/gl2ext.h>
-
+#if defined(__ANDROID__)
-#ifdef __ANDROID__
 // Weak-link all GL APIs included from this point on.
 // TODO: Annotate these with availability attributes for the
 // appropriate versions of Android, by including gl{3,31,31}.h and resetting
 // GL_APICALL for each.
 #undef GL_APICALL
 #define GL_APICALL __attribute__((weak_import)) KHRONOS_APICALL
-#endif  // __ANDROID__
+#endif  // defined(__ANDROID__)
 
 #include <GLES3/gl32.h>
 

mediapipe/gpu/gl_calculator_helper_impl.h

@@ -83,6 +83,10 @@ class GlCalculatorHelperImpl {
   GLuint framebuffer_ = 0;
 
   GpuResources& gpu_resources_;
+
+  // Necessary to compute for a given GlContext in order to properly enforce the
+  // SetStandardTextureParams.
+  bool can_linear_filter_float_textures_;
 };
 
 }  // namespace mediapipe

mediapipe/gpu/gl_calculator_helper_impl_common.cc

@@ -22,6 +22,17 @@ GlCalculatorHelperImpl::GlCalculatorHelperImpl(CalculatorContext* cc,
                                                GpuResources* gpu_resources)
     : gpu_resources_(*gpu_resources) {
   gl_context_ = gpu_resources_.gl_context(cc);
+// GL_ES_VERSION_2_0 and up (at least through ES 3.2) may contain the extension.
+// Checking against one also checks against higher ES versions. So this checks
+// against GLES >= 2.0.
+#if GL_ES_VERSION_2_0
+  // No linear float filtering by default, check extensions.
+  can_linear_filter_float_textures_ =
+      gl_context_->HasGlExtension("OES_texture_float_linear");
+#else
+  // Any float32 texture we create should automatically have linear filtering.
+  can_linear_filter_float_textures_ = true;
+#endif  // GL_ES_VERSION_2_0
 }
 
 GlCalculatorHelperImpl::~GlCalculatorHelperImpl() {
@@ -89,13 +100,15 @@ void GlCalculatorHelperImpl::BindFramebuffer(const GlTexture& dst) {
 
 void GlCalculatorHelperImpl::SetStandardTextureParams(GLenum target,
                                                       GLint internal_format) {
+  // Default to using linear filter everywhere. For float32 textures, fall back
+  // to GL_NEAREST if linear filtering unsupported.
   GLint filter;
   switch (internal_format) {
     case GL_R32F:
     case GL_RGBA32F:
-      // 32F (unlike 16f) textures do not support texture filtering
+      // 32F (unlike 16f) textures do not always support texture filtering
       // (According to OpenGL ES specification [TEXTURE IMAGE SPECIFICATION])
-      filter = GL_NEAREST;
+      filter = can_linear_filter_float_textures_ ? GL_LINEAR : GL_NEAREST;
       break;
     default:
       filter = GL_LINEAR;

mediapipe/gpu/gl_context.cc

@@ -203,6 +203,69 @@ bool GlContext::ParseGlVersion(absl::string_view version_string, GLint* major,
   return true;
 }
 
+bool GlContext::HasGlExtension(absl::string_view extension) const {
+  return gl_extensions_.find(extension) != gl_extensions_.end();
+}
+
+// Function for GL3.0+ to query for and store all of our available GL extensions
+// in an easily-accessible set.  The glGetString call is actually *not* required
+// to work with GL_EXTENSIONS for newer GL versions, so we must maintain both
+// variations of this function.
+::mediapipe::Status GlContext::GetGlExtensions() {
+  gl_extensions_.clear();
+  // glGetStringi only introduced in GL 3.0+; so we exit out this function if
+  // we don't have that function defined, regardless of version number reported.
+  // The function itself is also fully stubbed out if we're linking against an
+  // API version without a glGetStringi declaration. Although Emscripten
+  // sometimes provides this function, its default library implementation
+  // appears to only provide glGetString, so we skip this for Emscripten
+  // platforms to avoid possible undefined symbol or runtime errors.
+#if (GL_VERSION_3_0 || GL_ES_VERSION_3_0) && !defined(__EMSCRIPTEN__)
+  if (!SymbolAvailable(&glGetStringi)) {
+    LOG(ERROR) << "GL major version > 3.0 indicated, but glGetStringi not "
+               << "defined. Falling back to deprecated GL extensions querying "
+               << "method.";
+    return ::mediapipe::InternalError("glGetStringi not defined, but queried");
+  }
+  int num_extensions = 0;
+  glGetIntegerv(GL_NUM_EXTENSIONS, &num_extensions);
+  if (glGetError() != 0) {
+    return ::mediapipe::InternalError(
+        "Error querying for number of extensions");
+  }
+
+  for (int i = 0; i < num_extensions; ++i) {
+    const GLubyte* res = glGetStringi(GL_EXTENSIONS, i);
+    if (glGetError() != 0 || res == nullptr) {
+      return ::mediapipe::InternalError(
+          "Error querying for an extension by index");
+    }
+    const char* signed_res = reinterpret_cast<const char*>(res);
+    gl_extensions_.insert(signed_res);
+  }
+
+  return ::mediapipe::OkStatus();
+#else
+  return ::mediapipe::InternalError("GL version mismatch in GlGetExtensions");
+#endif  // (GL_VERSION_3_0 || GL_ES_VERSION_3_0) && !defined(__EMSCRIPTEN__)
+}
+
+// Same as GetGlExtensions() above, but for pre-GL3.0, where glGetStringi did
+// not exist.
+::mediapipe::Status GlContext::GetGlExtensionsCompat() {
+  gl_extensions_.clear();
+
+  const GLubyte* res = glGetString(GL_EXTENSIONS);
+  if (glGetError() != 0 || res == nullptr) {
+    LOG(ERROR) << "Error querying for GL extensions";
+    return ::mediapipe::InternalError("Error querying for GL extensions");
+  }
+  const char* signed_res = reinterpret_cast<const char*>(res);
+  gl_extensions_ = absl::StrSplit(signed_res, ' ');
+
+  return ::mediapipe::OkStatus();
+}
+
 ::mediapipe::Status GlContext::FinishInitialization(bool create_thread) {
   if (create_thread) {
     thread_ = absl::make_unique<GlContext::DedicatedThread>();
@@ -232,8 +295,13 @@ bool GlContext::ParseGlVersion(absl::string_view version_string, GLint* major,
 
     LOG(INFO) << "GL version: " << gl_major_version_ << "." << gl_minor_version_
               << " (" << glGetString(GL_VERSION) << ")";
-
+    if (gl_major_version_ >= 3) {
+      auto status = GetGlExtensions();
+      if (status.ok()) {
         return ::mediapipe::OkStatus();
+      }
+    }
+    return GetGlExtensionsCompat();
   });
 }
 

mediapipe/gpu/gl_context.h

@@ -237,6 +237,10 @@ class GlContext : public std::enable_shared_from_this<GlContext> {
   static bool ParseGlVersion(absl::string_view version_string, GLint* major,
                              GLint* minor);
 
+  // Simple query for GL extension support; only valid after GlContext has
+  // finished its initialization successfully.
+  bool HasGlExtension(absl::string_view extension) const;
+
   int64_t gl_finish_count() { return gl_finish_count_; }
 
   // Used by GlFinishSyncPoint. The count_to_pass cannot exceed the current
@@ -346,6 +350,8 @@ class GlContext : public std::enable_shared_from_this<GlContext> {
   bool HasContext() const;
   bool CheckForGlErrors();
   void LogUncheckedGlErrors(bool had_gl_errors);
+  ::mediapipe::Status GetGlExtensions();
+  ::mediapipe::Status GetGlExtensionsCompat();
 
   // The following ContextBinding functions have platform-specific
   // implementations.
@@ -366,6 +372,10 @@ class GlContext : public std::enable_shared_from_this<GlContext> {
   GLint gl_major_version_ = 0;
   GLint gl_minor_version_ = 0;
 
+  // glGetString and glGetStringi both return pointers to static strings,
+  // so we should be fine storing the extension pieces as string_view's.
+  std::set<absl::string_view> gl_extensions_;
+
   // Number of glFinish calls completed on the GL thread.
   // Changes should be guarded by mutex_. However, we use simple atomic
   // loads for efficiency on the fast path.

mediapipe/gpu/gl_simple_shaders.cc

@@ -24,6 +24,19 @@ namespace mediapipe {
 #define _STRINGIFY(_x) __STRINGIFY(_x)
 #endif
 
+// Our fragment shaders use DEFAULT_PRECISION to define the default precision
+// for a type. The macro strips out the precision declaration on desktop GL,
+// where it's not supported.
+//
+// Note: this does not use a raw std::string because some compilers don't handle
+// raw strings inside macros correctly. It uses a macro because we want to be
+// able to concatenate strings by juxtaposition. We want to concatenate strings
+// by juxtaposition so we can export const char* static data containing the
+// pre-expanded strings.
+//
+// TODO: this was written before we could rely on C++11 support.
+// Consider replacing it with constexpr std::string concatenation, or replacing
+// the static variables with functions.
 #define PRECISION_COMPAT                              \
   GLES_VERSION_COMPAT                                 \
   "#ifdef GL_ES \n"                                   \
@@ -42,10 +55,15 @@ namespace mediapipe {
   "#define out varying\n"   \
   "#endif  // __VERSION__ < 130\n"
 
+// Note: on systems where highp precision for floats is not supported (look up
+// GL_FRAGMENT_PRECISION_HIGH), we replace it with mediump.
 #define FRAGMENT_PREAMBLE                             \
   PRECISION_COMPAT                                    \
   "#if __VERSION__ < 130\n"                           \
   "#define in varying\n"                              \
+  "#if GL_ES && !GL_FRAGMENT_PRECISION_HIGH\n"        \
+  "#define highp mediump\n"                           \
+  "#endif  // GL_ES && !GL_FRAGMENT_PRECISION_HIGH\n" \
   "#endif  // __VERSION__ < 130\n"
 
 const GLchar* const kMediaPipeVertexShaderPreamble = VERTEX_PREAMBLE;

mediapipe/graphs/hair_segmentation/BUILD

@@ -12,6 +12,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+load(
+    "//mediapipe/framework/tool:mediapipe_graph.bzl",
+    "mediapipe_binary_graph",
+)
+
 licenses(["notice"])  # Apache 2.0
 
 package(default_visibility = ["//visibility:public"])
@@ -33,9 +38,19 @@ cc_library(
     ],
 )
 
-load(
+cc_library(
-    "//mediapipe/framework/tool:mediapipe_graph.bzl",
+    name = "desktop_calculators",
-    "mediapipe_binary_graph",
+    deps = [
+        "//mediapipe/calculators/core:flow_limiter_calculator",
+        "//mediapipe/calculators/core:previous_loopback_calculator",
+        "//mediapipe/calculators/image:image_transformation_calculator",
+        "//mediapipe/calculators/image:recolor_calculator",
+        "//mediapipe/calculators/image:set_alpha_calculator",
+        "//mediapipe/calculators/tflite:tflite_converter_calculator",
+        "//mediapipe/calculators/tflite:tflite_custom_op_resolver_calculator",
+        "//mediapipe/calculators/tflite:tflite_inference_calculator",
+        "//mediapipe/calculators/tflite:tflite_tensors_to_segmentation_calculator",
+    ],
 )
 
 mediapipe_binary_graph(

mediapipe/graphs/hair_segmentation/hair_segmentation_desktop_live.pbtxt

@@ -0,0 +1,152 @@
+# MediaPipe graph that performs hair segmentation with TensorFlow Lite on CPU.
+# Used in the example in
+# mediapipie/examples/desktop/hair_segmentation:hair_segmentation_cpu
+
+# Images on CPU coming into and out of the graph.
+input_stream: "input_video"
+output_stream: "output_video"
+
+# Throttles the images flowing downstream for flow control. It passes through
+# the very first incoming image unaltered, and waits for
+# TfLiteTensorsToSegmentationCalculator downstream in the graph to finish
+# generating the corresponding hair mask before it passes through another
+# image. All images that come in while waiting are dropped, limiting the number
+# of in-flight images between this calculator and
+# TfLiteTensorsToSegmentationCalculator to 1. This prevents the nodes in between
+# from queuing up incoming images and data excessively, which leads to increased
+# latency and memory usage, unwanted in real-time mobile applications. It also
+# eliminates unnecessarily computation, e.g., a transformed image produced by
+# ImageTransformationCalculator may get dropped downstream if the subsequent
+# TfLiteConverterCalculator or TfLiteInferenceCalculator is still busy
+# processing previous inputs.
+node {
+  calculator: "FlowLimiterCalculator"
+  input_stream: "input_video"
+  input_stream: "FINISHED:hair_mask"
+  input_stream_info: {
+    tag_index: "FINISHED"
+    back_edge: true
+  }
+  output_stream: "throttled_input_video"
+}
+
+# Transforms the input image on CPU to a 512x512 image. To scale the image, by
+# default it uses the STRETCH scale mode that maps the entire input image to the
+# entire transformed image. As a result, image aspect ratio may be changed and
+# objects in the image may be deformed (stretched or squeezed), but the hair
+# segmentation model used in this graph is agnostic to that deformation.
+node: {
+  calculator: "ImageTransformationCalculator"
+  input_stream: "IMAGE:throttled_input_video"
+  output_stream: "IMAGE:transformed_input_video"
+  node_options: {
+    [type.googleapis.com/mediapipe.ImageTransformationCalculatorOptions] {
+      output_width: 512
+      output_height: 512
+    }
+  }
+}
+
+# Caches a mask fed back from the previous round of hair segmentation, and upon
+# the arrival of the next input image sends out the cached mask with the
+# timestamp replaced by that of the input image, essentially generating a packet
+# that carries the previous mask. Note that upon the arrival of the very first
+# input image, an empty packet is sent out to jump start the feedback loop.
+node {
+  calculator: "PreviousLoopbackCalculator"
+  input_stream: "MAIN:throttled_input_video"
+  input_stream: "LOOP:hair_mask"
+  input_stream_info: {
+    tag_index: "LOOP"
+    back_edge: true
+  }
+  output_stream: "PREV_LOOP:previous_hair_mask"
+}
+
+# Embeds the hair mask generated from the previous round of hair segmentation
+# as the alpha channel of the current input image.
+node {
+  calculator: "SetAlphaCalculator"
+  input_stream: "IMAGE:transformed_input_video"
+  input_stream: "ALPHA:previous_hair_mask"
+  output_stream: "IMAGE:mask_embedded_input_video"
+}
+
+# Converts the transformed input image on CPU into an image tensor stored in
+# TfLiteTensor. The zero_center option is set to false to normalize the
+# pixel values to [0.f, 1.f] as opposed to [-1.f, 1.f]. With the
+# max_num_channels option set to 4, all 4 RGBA channels are contained in the
+# image tensor.
+node {
+  calculator: "TfLiteConverterCalculator"
+  input_stream: "IMAGE:mask_embedded_input_video"
+  output_stream: "TENSORS:image_tensor"
+  node_options: {
+    [type.googleapis.com/mediapipe.TfLiteConverterCalculatorOptions] {
+      zero_center: false
+      max_num_channels: 4
+    }
+  }
+}
+
+# Generates a single side packet containing a TensorFlow Lite op resolver that
+# supports custom ops needed by the model used in this graph.
+node {
+  calculator: "TfLiteCustomOpResolverCalculator"
+  output_side_packet: "op_resolver"
+  node_options: {
+    [type.googleapis.com/mediapipe.TfLiteCustomOpResolverCalculatorOptions] {
+      use_gpu: false
+    }
+  }
+}
+
+# Runs a TensorFlow Lite model on CPU that takes an image tensor and outputs a
+# tensor representing the hair segmentation, which has the same width and height
+# as the input image tensor.
+node {
+  calculator: "TfLiteInferenceCalculator"
+  input_stream: "TENSORS:image_tensor"
+  output_stream: "TENSORS:segmentation_tensor"
+  input_side_packet: "CUSTOM_OP_RESOLVER:op_resolver"
+  node_options: {
+    [type.googleapis.com/mediapipe.TfLiteInferenceCalculatorOptions] {
+      model_path: "mediapipe/models/hair_segmentation.tflite"
+      use_gpu: false
+    }
+  }
+}
+
+# Decodes the segmentation tensor generated by the TensorFlow Lite model into a
+# mask of values in [0, 255], stored in a CPU buffer. It also
+# takes the mask generated previously as another input to improve the temporal
+# consistency.
+node {
+  calculator: "TfLiteTensorsToSegmentationCalculator"
+  input_stream: "TENSORS:segmentation_tensor"
+  input_stream: "PREV_MASK:previous_hair_mask"
+  output_stream: "MASK:hair_mask"
+  node_options: {
+    [type.googleapis.com/mediapipe.TfLiteTensorsToSegmentationCalculatorOptions] {
+      tensor_width: 512
+      tensor_height: 512
+      tensor_channels: 2
+      combine_with_previous_ratio: 0.9
+      output_layer_index: 1
+    }
+  }
+}
+
+# Colors the hair segmentation with the color specified in the option.
+node {
+  calculator: "RecolorCalculator"
+  input_stream: "IMAGE:throttled_input_video"
+  input_stream: "MASK:hair_mask"
+  output_stream: "IMAGE:output_video"
+  node_options: {
+    [type.googleapis.com/mediapipe.RecolorCalculatorOptions] {
+      color { r: 0 g: 0 b: 255 }
+      mask_channel: RED
+    }
+  }
+}

mediapipe/java/com/google/mediapipe/mediapipe_aar.bzl

@@ -78,6 +78,33 @@ cat > $(OUTS) <<EOF
         srcs = ["//mediapipe/framework/formats:protos_src"],
     )
 
+    _proto_java_src_generator(
+        name = "rasterization_proto",
+        proto_src = "mediapipe/framework/formats/annotation/rasterization.proto",
+        java_lite_out = "com/google/mediapipe/formats/annotation/proto/RasterizationProto.java",
+        srcs = ["//mediapipe/framework/formats/annotation:protos_src"],
+    )
+
+    _proto_java_src_generator(
+        name = "location_data_proto",
+        proto_src = "mediapipe/framework/formats/location_data.proto",
+        java_lite_out = "com/google/mediapipe/formats/proto/LocationDataProto.java",
+        srcs = [
+            "//mediapipe/framework/formats:protos_src",
+            "//mediapipe/framework/formats/annotation:protos_src",
+        ],
+    )
+
+    _proto_java_src_generator(
+        name = "detection_proto",
+        proto_src = "mediapipe/framework/formats/detection.proto",
+        java_lite_out = "com/google/mediapipe/formats/proto/DetectionProto.java",
+        srcs = [
+            "//mediapipe/framework/formats:protos_src",
+            "//mediapipe/framework/formats/annotation:protos_src",
+        ],
+    )
+
     android_library(
         name = name + "_android_lib",
         srcs = [
@@ -86,6 +113,9 @@ cat > $(OUTS) <<EOF
             "//mediapipe/java/com/google/mediapipe/glutil:java_src",
             "com/google/mediapipe/proto/CalculatorProto.java",
             "com/google/mediapipe/formats/proto/LandmarkProto.java",
+            "com/google/mediapipe/formats/proto/DetectionProto.java",
+            "com/google/mediapipe/formats/proto/LocationDataProto.java",
+            "com/google/mediapipe/formats/annotation/proto/RasterizationProto.java",
         ],
         manifest = "AndroidManifest.xml",
         proguard_specs = ["//mediapipe/java/com/google/mediapipe/framework:proguard.pgcfg"],

mediapipe/objc/BUILD

@@ -43,31 +43,6 @@ MEDIAPIPE_IOS_HDRS = [
     "NSError+util_status.h",
 ]
 
-MEDIAPIPE_IOS_CC_DEPS = [
-    ":CFHolder",
-    ":util",
-    "//mediapipe/framework/port:map_util",
-    "//mediapipe/framework/port:ret_check",
-    "//mediapipe/framework/port:source_location",
-    "//mediapipe/framework/port:status",
-    "//mediapipe/framework/port:statusor",
-    "//mediapipe/framework/port:threadpool",
-    "//mediapipe/framework:calculator_framework",
-    "//mediapipe/framework:mediapipe_profiling",
-    "//mediapipe/gpu:MPPGraphGPUData",
-    "//mediapipe/gpu:pixel_buffer_pool_util",
-    "//mediapipe/gpu:gpu_buffer",
-    "//mediapipe/gpu:gl_base",
-    "//mediapipe/gpu:gpu_shared_data_internal",
-    "//mediapipe/gpu:graph_support",
-    # Other deps
-    "//mediapipe/util:cpu_util",
-    "@com_google_absl//absl/base:core_headers",
-    "@com_google_absl//absl/memory",
-    "@com_google_absl//absl/strings",
-    "@com_google_absl//absl/synchronization",
-]
-
 objc_library(
     name = "mediapipe_framework_ios",
     srcs = MEDIAPIPE_IOS_SRCS,
@@ -80,8 +55,28 @@ objc_library(
         "Accelerate",
     ],
     visibility = ["//mediapipe/framework:mediapipe_internal"],
-    deps = MEDIAPIPE_IOS_CC_DEPS + [
+    deps = [
-        # These are objc_library deps.
+        ":CFHolder",
+        ":util",
+        "//mediapipe/framework:calculator_framework",
+        "//mediapipe/framework:mediapipe_profiling",
+        "//mediapipe/framework/port:map_util",
+        "//mediapipe/framework/port:ret_check",
+        "//mediapipe/framework/port:source_location",
+        "//mediapipe/framework/port:status",
+        "//mediapipe/framework/port:statusor",
+        "//mediapipe/framework/port:threadpool",
+        "//mediapipe/gpu:MPPGraphGPUData",
+        "//mediapipe/gpu:gl_base",
+        "//mediapipe/gpu:gpu_buffer",
+        "//mediapipe/gpu:gpu_shared_data_internal",
+        "//mediapipe/gpu:graph_support",
+        "//mediapipe/gpu:pixel_buffer_pool_util",
+        "//mediapipe/util:cpu_util",
+        "@com_google_absl//absl/base:core_headers",
+        "@com_google_absl//absl/memory",
+        "@com_google_absl//absl/strings",
+        "@com_google_absl//absl/synchronization",
         "@google_toolbox_for_mac//:GTM_Defines",
     ],
 )

mediapipe/util/annotation_renderer.cc

@@ -426,7 +426,7 @@ void AnnotationRenderer::DrawPoint(const RenderAnnotation& annotation) {
   cv::Point point_to_draw(x, y);
   const cv::Scalar color = MediapipeColorToOpenCVColor(annotation.color());
   const int thickness = annotation.thickness();
-  cv::circle(mat_image_, point_to_draw, thickness, color, thickness);
+  cv::circle(mat_image_, point_to_draw, thickness, color, -1);
 }
 
 void AnnotationRenderer::DrawLine(const RenderAnnotation& annotation) {

mediapipe/util/sequence/BUILD

@@ -22,7 +22,6 @@ cc_library(
     hdrs = ["media_sequence_util.h"],
     visibility = [
         "//mediapipe:__subpackages__",
-        "//research/action_recognition/sequence:__subpackages__",
     ],
     deps = [
         "//mediapipe/framework/port:core_proto",
@@ -38,7 +37,6 @@ cc_library(
     hdrs = ["media_sequence.h"],
     visibility = [
         "//mediapipe:__subpackages__",
-        "//research/action_recognition/sequence:__subpackages__",
     ],
     deps = [
         ":media_sequence_util",

setup_opencv.sh

@@ -36,7 +36,11 @@ cd /tmp/build_opencv
 git clone https://github.com/opencv/opencv_contrib.git
 git clone https://github.com/opencv/opencv.git
 mkdir opencv/release
-cd opencv/release
+cd opencv_contrib
+git checkout 3.4
+cd ../opencv
+git checkout 3.4
+cd release
 cmake .. -DCMAKE_BUILD_TYPE=RELEASE -DCMAKE_INSTALL_PREFIX=/usr/local \
       -DBUILD_TESTS=OFF -DBUILD_PERF_TESTS=OFF -DBUILD_opencv_ts=OFF \
       -DOPENCV_EXTRA_MODULES_PATH=/tmp/build_opencv/opencv_contrib/modules \

third_party/org_tensorflow_9696366bcadab23a25c773b3ed405bac8ded4d0d.diff

@@ -0,0 +1,112 @@
+diff --git a/third_party/cpuinfo/BUILD.bazel b/third_party/cpuinfo/BUILD.bazel
+index 8d89521612..6ea60acdda 100644
+--- a/third_party/cpuinfo/BUILD.bazel
++++ b/third_party/cpuinfo/BUILD.bazel
+@@ -116,6 +111,8 @@ cc_library(
+         ":watchos_x86": COMMON_SRCS + X86_SRCS + MACH_SRCS + MACH_X86_SRCS,
+         ":watchos_armv7k": COMMON_SRCS + MACH_SRCS + MACH_ARM_SRCS,
+         ":watchos_arm64_32": COMMON_SRCS + MACH_SRCS + MACH_ARM_SRCS,
++        ":tvos_x86_64": COMMON_SRCS + X86_SRCS + MACH_SRCS + MACH_X86_SRCS,
++        ":tvos_arm64": COMMON_SRCS + MACH_SRCS + MACH_ARM_SRCS,
+         ":emscripten_wasm": COMMON_SRCS + EMSCRIPTEN_SRCS,
+     }),
+     copts = C99OPTS + [
+@@ -212,7 +209,7 @@ config_setting(
+ config_setting(
+     name = "ios_armv7",
+     values = {
+-        "crosstool_top": "//tools/osx/crosstool:crosstool",
++        "apple_platform_type": "ios",
+         "cpu": "ios_armv7",
+     },
+ )
+@@ -220,7 +217,7 @@ config_setting(
+ config_setting(
+     name = "ios_arm64",
+     values = {
+-        "crosstool_top": "//tools/osx/crosstool:crosstool",
++        "apple_platform_type": "ios",
+         "cpu": "ios_arm64",
+     },
+ )
+@@ -228,7 +225,7 @@ config_setting(
+ config_setting(
+     name = "ios_arm64e",
+     values = {
+-        "crosstool_top": "//tools/osx/crosstool:crosstool",
++        "apple_platform_type": "ios",
+         "cpu": "ios_arm64e",
+     },
+ )
+@@ -236,7 +233,7 @@ config_setting(
+ config_setting(
+     name = "ios_x86",
+     values = {
+-        "crosstool_top": "//tools/osx/crosstool:crosstool",
++        "apple_platform_type": "ios",
+         "cpu": "ios_i386",
+     },
+ )
+@@ -244,7 +241,7 @@ config_setting(
+ config_setting(
+     name = "ios_x86_64",
+     values = {
+-        "crosstool_top": "//tools/osx/crosstool:crosstool",
++        "apple_platform_type": "ios",
+         "cpu": "ios_x86_64",
+     },
+ )
+@@ -252,7 +249,7 @@ config_setting(
+ config_setting(
+     name = "watchos_armv7k",
+     values = {
+-        "crosstool_top": "//tools/osx/crosstool:crosstool",
++        "apple_platform_type": "watchos",
+         "cpu": "watchos_armv7k",
+     },
+ )
+@@ -260,7 +257,7 @@ config_setting(
+ config_setting(
+     name = "watchos_arm64_32",
+     values = {
+-        "crosstool_top": "//tools/osx/crosstool:crosstool",
++        "apple_platform_type": "watchos",
+         "cpu": "watchos_arm64_32",
+     },
+ )
+@@ -268,7 +265,7 @@ config_setting(
+ config_setting(
+     name = "watchos_x86",
+     values = {
+-        "crosstool_top": "//tools/osx/crosstool:crosstool",
++        "apple_platform_type": "watchos",
+         "cpu": "watchos_i386",
+     },
+ )
+@@ -276,7 +273,7 @@ config_setting(
+ config_setting(
+     name = "watchos_x86_64",
+     values = {
+-        "crosstool_top": "//tools/osx/crosstool:crosstool",
++        "apple_platform_type": "watchos",
+         "cpu": "watchos_x86_64",
+     },
+ )
+@@ -284,7 +281,7 @@ config_setting(
+ config_setting(
+     name = "tvos_arm64",
+     values = {
+-        "crosstool_top": "//tools/osx/crosstool:crosstool",
++        "apple_platform_type": "tvos",
+         "cpu": "tvos_arm64",
+     },
+ )
+@@ -292,7 +289,7 @@ config_setting(
+ config_setting(
+     name = "tvos_x86_64",
+     values = {
+-        "crosstool_top": "//tools/osx/crosstool:crosstool",
++        "apple_platform_type": "tvos",
+         "cpu": "tvos_x86_64",
+     },
+ )