Decouple capture timestamp and reference time

content/renderer/media/video_capture_impl_unittest.cc

 // Copyright (c) 2012 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 <stddef.h>
 
 #include "base/macros.h"
 #include "base/memory/shared_memory.h"
 #include "base/message_loop/message_loop.h"
 #include "content/child/child_process.h"
@@ skipping 150 matching lines @@
     video_capture_impl_->StopCapture(client_id);
   }
 
   void NewBuffer(int buffer_id, const base::SharedMemory& shm) {
     video_capture_impl_->OnBufferCreated(
         base::SharedMemory::DuplicateHandle(shm.handle()),
         shm.mapped_size(), buffer_id);
   }
 
   void BufferReceived(int buffer_id, const gfx::Size& size) {
+    base::TimeTicks now = base::TimeTicks::Now();
+    base::TimeDelta timestamp = now - base::TimeTicks();
+
+    int64_t internal_value = now.ToInternalValue();

[miu, 2016/06/08 19:24:44]

This might break in the future if VideoFrameMetadata changes. Instead, I
suggest:

  media::VideoFrameMetadata md;
  md.SetTimeTicks(REFERENCE_TIME, ...);
  base::DictionaryValue dict;
  md.MergeInternalValuesInto(&dict);

...and then pass dict to OnBufferReceived().

[qiangchen, 2016/06/08 20:08:55]

Done.

+    base::DictionaryValue metadata;
+    metadata.SetWithoutPathExpansion(
+        base::IntToString(
+            static_cast<int>(media::VideoFrameMetadata::REFERENCE_TIME)),
+        base::BinaryValue::CreateWithCopiedBuffer(
+            reinterpret_cast<const char*>(&internal_value),
+            sizeof(internal_value)));
+
     video_capture_impl_->OnBufferReceived(
-        buffer_id, base::TimeTicks::Now(), base::DictionaryValue(),
-        media::PIXEL_FORMAT_I420, media::VideoFrame::STORAGE_SHMEM, size,
-        gfx::Rect(size));
+        buffer_id, timestamp, metadata, media::PIXEL_FORMAT_I420,
+        media::VideoFrame::STORAGE_SHMEM, size, gfx::Rect(size));
   }
 
   void BufferDestroyed(int buffer_id) {
     video_capture_impl_->OnBufferDestroyed(buffer_id);
   }
 
   void DeInit() {
     video_capture_impl_->DeInit();
   }
 
@@ skipping 187 matching lines @@
    StartCapture(0, params_small_);
 
    // Receive state change message from browser.
    video_capture_impl_->ReceiveStateChangeMessage(VIDEO_CAPTURE_STATE_ERROR);
 
    StopCapture(0);
    DeInit();
 }
 
 }  // namespace content