Added Object detection result helpers

mediapipe/tasks/ios/vision/object_detector/utils/BUILD

@@ -0,0 +1,28 @@
+# Copyright 2023 The MediaPipe Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+package(default_visibility = ["//mediapipe/tasks:internal"])
+
+licenses(["notice"])
+
+objc_library(
+    name = "MPPObjectDetectionResultHelpers",
+    srcs = ["sources/MPPObjectDetectionResult+Helpers.mm"],
+    hdrs = ["sources/MPPObjectDetectionResult+Helpers.h"],
+    deps = [
+        "//mediapipe/framework:packet",
+        "//mediapipe/tasks/ios/components/containers/utils:MPPDetectionHelpers",
+        "//mediapipe/tasks/ios/vision/object_detector:MPPObjectDetectionResult",
+    ],
+)

mediapipe/tasks/ios/vision/object_detector/utils/sources/MPPObjectDetectionResult+Helpers.h

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+// Copyright 2023 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.
+
+#import "mediapipe/tasks/ios/vision/object_detector/sources/MPPObjectDetectionResult.h"
+
+#include "mediapipe/framework/packet.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface MPPObjectDetectionResult (Helpers)
+
+/**
+ * Creates an `MPPObjectDetectionResult` from a MediaPipe packet containing a
+ * `std::vector<DetectionProto>`.
+ *
+ * @param packet a MediaPipe packet wrapping a `std::vector<DetectionProto>`.
+ *
+ * @return  An `MPPObjectDetectionResult` object that contains a list of detections.
+ */
++ (nullable MPPObjectDetectionResult *)objectDetectionResultWithDetectionsPacket:
+    (const mediapipe::Packet &)packet;
+
+@end
+
+NS_ASSUME_NONNULL_END

mediapipe/tasks/ios/vision/object_detector/utils/sources/MPPObjectDetectionResult+Helpers.mm

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+// Copyright 2023 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.
+
+#import "mediapipe/tasks/ios/vision/object_detector/utils/sources/MPPObjectDetectionResult+Helpers.h"
+
+#import "mediapipe/tasks/ios/components/containers/utils/sources/MPPDetection+Helpers.h"
+
+static const int kMicroSecondsPerMilliSecond = 1000;
+
+namespace {
+using DetectionProto = ::mediapipe::Detection;
+using ::mediapipe::Packet;
+}  // namespace
+
+@implementation MPPObjectDetectionResult (Helpers)
+
++ (nullable MPPObjectDetectionResult *)objectDetectionResultWithDetectionsPacket:
+    (const Packet &)packet {
+  if (!packet.ValidateAsType<std::vector<DetectionProto>>().ok()) {
+    return nil;
+  }
+
+  const std::vector<DetectionProto> &detectionProtos = packet.Get<std::vector<DetectionProto>>();
+
+  NSMutableArray<MPPDetection *> *detections =
+      [NSMutableArray arrayWithCapacity:(NSUInteger)detectionProtos.size()];
+  for (const auto &detectionProto : detectionProtos) {
+    [detections addObject:[MPPDetection detectionWithProto:detectionProto]];
+  }
+
+  return [[MPPObjectDetectionResult alloc]
+      initWithDetections:detections
+             timestampMs:(NSInteger)(packet.Timestamp().Value() / kMicroSecondsPerMilliSecond)];
+}
+
+@end