Add content type information to encoded images and corresponding rtp extension header

webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_encoder.mm

 /*
  *  Copyright (c) 2015 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 346 matching lines @@
 }
 
 int H264VideoToolboxEncoder::InitEncode(const VideoCodec* codec_settings,
                                         int number_of_cores,
                                         size_t max_payload_size) {
   RTC_DCHECK(codec_settings);
   RTC_DCHECK_EQ(codec_settings->codecType, kVideoCodecH264);
 
   width_ = codec_settings->width;
   height_ = codec_settings->height;
+  mode_ = codec_settings->mode;
   // We can only set average bitrate on the HW encoder.
   target_bitrate_bps_ = codec_settings->startBitrate;
   bitrate_adjuster_.SetTargetBitrateBps(target_bitrate_bps_);
 
   // TODO(tkchin): Try setting payload size via
   // kVTCompressionPropertyKey_MaxH264SliceBytes.
 
   return ResetCompressionSession();
 }
 
@@ skipping 338 matching lines @@
   webrtc::EncodedImage frame(buffer->data(), buffer->size(), buffer->size());
   frame._encodedWidth = width;
   frame._encodedHeight = height;
   frame._completeFrame = true;
   frame._frameType =
       is_keyframe ? webrtc::kVideoFrameKey : webrtc::kVideoFrameDelta;
   frame.capture_time_ms_ = render_time_ms;
   frame._timeStamp = timestamp;
   frame.rotation_ = rotation;
 
+  frame.content_type_ =
+      (mode_ == kScreensharing) ? VideoContentType::SCREENSHARE : VideoContentType::UNSPECIFIED;
+
   h264_bitstream_parser_.ParseBitstream(buffer->data(), buffer->size());
   h264_bitstream_parser_.GetLastSliceQp(&frame.qp_);
 
   EncodedImageCallback::Result res =
       callback_->OnEncodedImage(frame, &codec_specific_info, header.get());
   if (res.error != EncodedImageCallback::Result::OK) {
     LOG(LS_ERROR) << "Encode callback failed: " << res.error;
     return;
   }
   bitrate_adjuster_.Update(frame._length);
 }
 
 VideoEncoder::ScalingSettings H264VideoToolboxEncoder::GetScalingSettings()
     const {
   return VideoEncoder::ScalingSettings(true, internal::kLowH264QpThreshold,
                                        internal::kHighH264QpThreshold);
 }
 }  // namespace webrtc