Add a field trial to produce VideoFrames in camera capturers.

webrtc/sdk/android/src/java/org/webrtc/Camera2Session.java

 /*
  *  Copyright 2016 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 package org.webrtc;
 
 import android.annotation.TargetApi;
 import android.content.Context;
+import android.graphics.Matrix;
 import android.graphics.SurfaceTexture;
 import android.hardware.camera2.CameraAccessException;
 import android.hardware.camera2.CameraCaptureSession;
 import android.hardware.camera2.CameraCharacteristics;
 import android.hardware.camera2.CameraDevice;
 import android.hardware.camera2.CameraManager;
 import android.hardware.camera2.CameraMetadata;
 import android.hardware.camera2.CaptureFailure;
 import android.hardware.camera2.CaptureRequest;
 import android.media.MediaRecorder;
@@ skipping 12 matching lines @@
 
   private static final Histogram camera2StartTimeMsHistogram =
       Histogram.createCounts("WebRTC.Android.Camera2.StartTimeMs", 1, 10000, 50);
   private static final Histogram camera2StopTimeMsHistogram =
       Histogram.createCounts("WebRTC.Android.Camera2.StopTimeMs", 1, 10000, 50);
   private static final Histogram camera2ResolutionHistogram = Histogram.createEnumeration(
       "WebRTC.Android.Camera2.Resolution", CameraEnumerationAndroid.COMMON_RESOLUTIONS.size());
 
   private static enum SessionState { RUNNING, STOPPED }
 
+  private final boolean videoFrameEmitTrialEnabled;
+
   private final Handler cameraThreadHandler;
   private final CreateSessionCallback callback;
   private final Events events;
   private final Context applicationContext;
   private final CameraManager cameraManager;
   private final SurfaceTextureHelper surfaceTextureHelper;
   private final Surface mediaRecorderSurface;
   private final String cameraId;
   private final int width;
   private final int height;
@@ skipping 161 matching lines @@
                 // Undo the mirror that the OS "helps" us with.
                 // http://developer.android.com/reference/android/hardware/Camera.html#setDisplayOrientation(int)
                 transformMatrix = RendererCommon.multiplyMatrices(
                     transformMatrix, RendererCommon.horizontalFlipMatrix());
               }
 
               // Undo camera orientation - we report it as rotation instead.
               transformMatrix =
                   RendererCommon.rotateTextureMatrix(transformMatrix, -cameraOrientation);
 
-              events.onTextureFrameCaptured(Camera2Session.this, captureFormat.width,
-                  captureFormat.height, oesTextureId, transformMatrix, rotation, timestampNs);
+              if (videoFrameEmitTrialEnabled) {
+                VideoFrame.Buffer buffer = surfaceTextureHelper.createTextureBuffer(
+                    captureFormat.width, captureFormat.height,
+                    RendererCommon.convertMatrixToAndroidGraphicsMatrix(transformMatrix));
+                final VideoFrame frame = new VideoFrame(buffer, rotation, timestampNs);
+                events.onFrameCaptured(Camera2Session.this, frame);
+                frame.release();
+              } else {
+                events.onTextureFrameCaptured(Camera2Session.this, captureFormat.width,
+                    captureFormat.height, oesTextureId, transformMatrix, rotation, timestampNs);
+              }
             }
           });
       Logging.d(TAG, "Camera device successfully started.");
       callback.onDone(Camera2Session.this);
     }
 
     // Prefers optical stabilization over software stabilization if available. Only enables one of
     // the stabilization modes at a time because having both enabled can cause strange results.
     private void chooseStabilizationMode(CaptureRequest.Builder captureRequestBuilder) {
       final int[] availableOpticalStabilization = cameraCharacteristics.get(
@@ skipping 54 matching lines @@
       SurfaceTextureHelper surfaceTextureHelper, MediaRecorder mediaRecorder, String cameraId,
       int width, int height, int framerate) {
     new Camera2Session(callback, events, applicationContext, cameraManager, surfaceTextureHelper,
         mediaRecorder, cameraId, width, height, framerate);
   }
 
   private Camera2Session(CreateSessionCallback callback, Events events, Context applicationContext,
       CameraManager cameraManager, SurfaceTextureHelper surfaceTextureHelper,
       MediaRecorder mediaRecorder, String cameraId, int width, int height, int framerate) {
     Logging.d(TAG, "Create new camera2 session on camera " + cameraId);
+    videoFrameEmitTrialEnabled =
+        PeerConnectionFactory.fieldTrialsFindFullName(PeerConnectionFactory.VIDEO_FRAME_EMIT_TRIAL)
+            .equals(PeerConnectionFactory.TRIAL_ENABLED);
 
     constructionTimeNs = System.nanoTime();
 
     this.cameraThreadHandler = new Handler();
     this.callback = callback;
     this.events = events;
     this.applicationContext = applicationContext;
     this.cameraManager = cameraManager;
     this.surfaceTextureHelper = surfaceTextureHelper;
     this.mediaRecorderSurface = (mediaRecorder != null) ? mediaRecorder.getSurface() : null;
@@ skipping 142 matching lines @@
     }
     return (cameraOrientation + rotation) % 360;
   }
 
   private void checkIsOnCameraThread() {
     if (Thread.currentThread() != cameraThreadHandler.getLooper().getThread()) {
       throw new IllegalStateException("Wrong thread");
     }
   }
 }