New class AdaptedVideoTrackSource.

webrtc/media/base/videobroadcaster.cc

 /*
  *  Copyright (c) 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.
  */
 
@@ skipping 27 matching lines @@
   VideoSourceBase::RemoveSink(sink);
   UpdateWants();
 }
 
 bool VideoBroadcaster::frame_wanted() const {
   rtc::CritScope cs(&sinks_and_wants_lock_);
   return !sink_pairs().empty();
 }
 
 VideoSinkWants VideoBroadcaster::wants() const {
-  RTC_DCHECK(thread_checker_.CalledOnValidThread());
   rtc::CritScope cs(&sinks_and_wants_lock_);
   return current_wants_;
 }
 
 void VideoBroadcaster::OnFrame(const cricket::VideoFrame& frame) {
   rtc::CritScope cs(&sinks_and_wants_lock_);
   for (auto& sink_pair : sink_pairs()) {
+    if (sink_pair.wants.rotation_applied &&
+        frame.rotation() != webrtc::kVideoRotation_0) {
+      // Calls to OnFrame are not synchronized with changes to the sink wants.
+      // When rotation_applied is set to true, one or a few frames may get here
+      // with rotation still pending. Protect sinks that don't expect any
+      // pending rotation.
+      LOG(LS_VERBOSE) << "Discarding frame with unexpected rotation.";
+      continue;
+    }
     if (sink_pair.wants.black_frames) {
       sink_pair.sink->OnFrame(cricket::WebRtcVideoFrame(
           GetBlackFrameBuffer(frame.width(), frame.height()), frame.rotation(),
           frame.timestamp_us(), frame.transport_frame_id()));
     } else {
       sink_pair.sink->OnFrame(frame);
     }
   }
 }
 
@@ skipping 36 matching lines @@
     rtc::scoped_refptr<webrtc::I420Buffer> buffer =
         new RefCountedObject<webrtc::I420Buffer>(width, height);
     buffer->SetToBlack();
     black_frame_buffer_ = buffer;
   }
 
   return black_frame_buffer_;
 }
 
 }  // namespace rtc