Shape Detection: use Google Play services Face detection where available

services/shape_detection/android/java/src/org/chromium/shape_detection/FaceDetectionImplGmsCore.java

Index: services/shape_detection/android/java/src/org/chromium/shape_detection/FaceDetectionImplGmsCore.java
diff --git a/services/shape_detection/android/java/src/org/chromium/shape_detection/FaceDetectionImplGmsCore.java b/services/shape_detection/android/java/src/org/chromium/shape_detection/FaceDetectionImplGmsCore.java
new file mode 100644
index 0000000000000000000000000000000000000000..e0c8394777a985ecf56c6aa41cf96285a93df1e6
--- /dev/null
+++ b/services/shape_detection/android/java/src/org/chromium/shape_detection/FaceDetectionImplGmsCore.java
@@ -0,0 +1,131 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.shape_detection;
+
+import android.content.Context;
+import android.graphics.PointF;
+import android.util.SparseArray;
+
+import com.google.android.gms.vision.Frame;
+import com.google.android.gms.vision.face.Face;
+import com.google.android.gms.vision.face.FaceDetector;
+import com.google.android.gms.vision.face.Landmark;
+
+import org.chromium.base.Log;
+import org.chromium.gfx.mojom.RectF;
+import org.chromium.mojo.system.MojoException;
+import org.chromium.mojo.system.SharedBufferHandle;
+import org.chromium.shape_detection.mojom.FaceDetection;
+import org.chromium.shape_detection.mojom.FaceDetectionResult;
+import org.chromium.shape_detection.mojom.FaceDetectorOptions;
+import org.chromium.shape_detection.mojom.LandmarkType;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Google Play services implementation of the FaceDetection service defined in
+ * services/shape_detection/public/interfaces/facedetection.mojom
+ */
+public class FaceDetectionImplGmsCore implements FaceDetection {
+    private static final String TAG = "FaceDetectionImpl";
+    private static final int MAX_FACES = 32;
+    private final int mMaxFaces;
+    private final boolean mFastMode;
+    private final FaceDetector mFaceDetector;
+
+    FaceDetectionImplGmsCore(Context context, FaceDetectorOptions options) {
+        FaceDetector.Builder builder = new FaceDetector.Builder(context);
+        mMaxFaces = Math.min(options.maxDetectedFaces, MAX_FACES);
+        mFastMode = options.fastMode;
+
+        try {
+            builder.setMode(mFastMode ? FaceDetector.FAST_MODE : FaceDetector.ACCURATE_MODE);
+            builder.setLandmarkType(FaceDetector.ALL_LANDMARKS);
+            if (mMaxFaces == 1) {
+                builder.setProminentFaceOnly(true);
+            }
+        } catch (IllegalArgumentException e) {
+            Log.e(TAG, "Unexpected exception " + e);
+            assert false;
+        }
+
+        mFaceDetector = builder.build();
+    }
+
+    @Override
+    public void detect(
+            SharedBufferHandle frameData, int width, int height, DetectResponse callback) {
+        // The vision library will be downloaded the first time the API is used
+        // on the device; this happens "fast", but it might have not completed,
+        // bail in this case.
+        if (!mFaceDetector.isOperational()) {
+            Log.e(TAG, "FaceDetector is not operational");
+
+            // Fallback to Android's FaceDetectionImpl.
+            FaceDetectorOptions options = new FaceDetectorOptions();
+            options.fastMode = mFastMode;
+            options.maxDetectedFaces = mMaxFaces;
+            FaceDetectionImpl detector = new FaceDetectionImpl(options);
+            detector.detect(frameData, width, height, callback);
+            return;
+        }
+
+        Frame frame = SharedBufferUtils.convertToFrame(frameData, width, height);
+        if (frame == null) {
+            Log.e(TAG, "Error converting SharedMemory to Frame");
+            callback.call(new FaceDetectionResult[0]);
+            return;
+        }
+
+        final SparseArray<Face> faces = mFaceDetector.detect(frame);
+
+        FaceDetectionResult[] faceArray = new FaceDetectionResult[faces.size()];
+        for (int i = 0; i < faces.size(); i++) {
+            faceArray[i] = new FaceDetectionResult();
+            final Face face = faces.valueAt(i);
+
+            final PointF corner = face.getPosition();
+            faceArray[i].boundingBox = new RectF();
+            faceArray[i].boundingBox.x = corner.x;
+            faceArray[i].boundingBox.y = corner.y;
+            faceArray[i].boundingBox.width = face.getWidth();
+            faceArray[i].boundingBox.height = face.getHeight();
+
+            final List<Landmark> landmarks = face.getLandmarks();
+            ArrayList<org.chromium.shape_detection.mojom.Landmark> mojoLandmarks =
+                    new ArrayList<org.chromium.shape_detection.mojom.Landmark>(landmarks.size());
+
+            for (int j = 0; j < landmarks.size(); j++) {
+                final Landmark landmark = landmarks.get(j);
+                final int landmarkType = landmark.getType();
+                if (landmarkType == Landmark.LEFT_EYE || landmarkType == Landmark.RIGHT_EYE
+                        || landmarkType == Landmark.BOTTOM_MOUTH) {
+                    org.chromium.shape_detection.mojom.Landmark mojoLandmark =
+                            new org.chromium.shape_detection.mojom.Landmark();
+                    mojoLandmark.location = new org.chromium.gfx.mojom.PointF();
+                    mojoLandmark.location.x = landmark.getPosition().x;
+                    mojoLandmark.location.y = landmark.getPosition().y;
+                    mojoLandmark.type = landmarkType == Landmark.BOTTOM_MOUTH ? LandmarkType.MOUTH
+                                                                              : LandmarkType.EYE;
+                    mojoLandmarks.add(mojoLandmark);
+                }
+            }
+            faceArray[i].landmarks = mojoLandmarks.toArray(
+                    new org.chromium.shape_detection.mojom.Landmark[mojoLandmarks.size()]);
+        }
+        callback.call(faceArray);
+    }
+
+    @Override
+    public void close() {
+        mFaceDetector.release();
+    }
+
+    @Override
+    public void onConnectionError(MojoException e) {
+        close();
+    }
+}