Decouple capture timestamp and reference time

content/browser/renderer_host/media/video_capture_device_client.cc

 // Copyright 2015 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.
 
 #include "content/browser/renderer_host/media/video_capture_device_client.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 67 matching lines @@
   // This should be on the platform auxiliary thread since
   // |external_jpeg_decoder_| need to be destructed on the same thread as
   // OnIncomingCapturedData.
 }
 
 void VideoCaptureDeviceClient::OnIncomingCapturedData(
     const uint8_t* data,
     int length,
     const VideoCaptureFormat& frame_format,
     int rotation,
-    const base::TimeTicks& timestamp) {
+    base::TimeTicks reference_time,
+    base::TimeDelta timestamp) {
   TRACE_EVENT0("video", "VideoCaptureDeviceClient::OnIncomingCapturedData");
   DCHECK_EQ(media::PIXEL_STORAGE_CPU, frame_format.pixel_storage);
 
   if (last_captured_pixel_format_ != frame_format.pixel_format) {
     OnLog("Pixel format: " +
           media::VideoPixelFormatToString(frame_format.pixel_format));
     last_captured_pixel_format_ = frame_format.pixel_format;
 
     if (frame_format.pixel_format == media::PIXEL_FORMAT_MJPEG &&
         !external_jpeg_decoder_initialized_) {
@@ skipping 118 matching lines @@
   DCHECK_GE(static_cast<size_t>(length), frame_format.ImageAllocationSize());
 
   if (external_jpeg_decoder_) {
     const VideoCaptureGpuJpegDecoder::STATUS status =
         external_jpeg_decoder_->GetStatus();
     if (status == VideoCaptureGpuJpegDecoder::FAILED) {
       external_jpeg_decoder_.reset();
     } else if (status == VideoCaptureGpuJpegDecoder::INIT_PASSED &&
         frame_format.pixel_format == media::PIXEL_FORMAT_MJPEG &&
         rotation == 0 && !flip) {
-      external_jpeg_decoder_->DecodeCapturedData(data, length, frame_format,
-                                                 timestamp, std::move(buffer));
+      external_jpeg_decoder_->DecodeCapturedData(
+          data, length, frame_format, reference_time, std::move(buffer));
       return;
     }
   }
 
   if (libyuv::ConvertToI420(data,
                             length,
                             y_plane_data,
                             yplane_stride,
                             u_plane_data,
                             uv_plane_stride,
                             v_plane_data,
                             uv_plane_stride,
                             crop_x,
                             crop_y,
                             frame_format.frame_size.width(),
                             (flip ? -1 : 1) * frame_format.frame_size.height(),
                             new_unrotated_width,
                             new_unrotated_height,
                             rotation_mode,
                             origin_colorspace) != 0) {
     DLOG(WARNING) << "Failed to convert buffer's pixel format to I420 from "
                   << media::VideoPixelFormatToString(frame_format.pixel_format);
     return;
   }
 
   const VideoCaptureFormat output_format = VideoCaptureFormat(
       dimensions, frame_format.frame_rate,
       media::PIXEL_FORMAT_I420, output_pixel_storage);
-  OnIncomingCapturedBuffer(std::move(buffer), output_format, timestamp);
+  OnIncomingCapturedBuffer(std::move(buffer), output_format, reference_time);

[miu, 2016/05/18 22:35:40]

See comment I made in video_capture_device.h. You'll want to continue passing
the frame |timestamp| through here and into OnIncomingCapturedBuffer().

[qiangchen, 2016/05/20 17:55:14]

Done.

 }
 
 std::unique_ptr<media::VideoCaptureDevice::Client::Buffer>
 VideoCaptureDeviceClient::ReserveOutputBuffer(
     const gfx::Size& frame_size,
     media::VideoPixelFormat pixel_format,
     media::VideoPixelStorage pixel_storage) {
   DCHECK_GT(frame_size.width(), 0);
   DCHECK_GT(frame_size.height(), 0);
   // Currently, only I420 pixel format is supported.
@@ skipping 148 matching lines @@
           reinterpret_cast<uint8_t*>(buffer->data(VideoFrame::kUPlane));
       *v_plane_data =
           reinterpret_cast<uint8_t*>(buffer->data(VideoFrame::kVPlane));
       return buffer;
   }
   NOTREACHED();
   return std::unique_ptr<Buffer>();
 }
 
 }  // namespace content