Implement WebRTC in Chrome for TV

content/renderer/media/rtc_video_decoder_bridge_tv.h

Index: content/renderer/media/rtc_video_decoder_bridge_tv.h
diff --git a/content/renderer/media/rtc_video_decoder_bridge_tv.h b/content/renderer/media/rtc_video_decoder_bridge_tv.h
new file mode 100644
index 0000000000000000000000000000000000000000..372fdc9bb4b41250ea3446f02c82afc04b72f46e
--- /dev/null
+++ b/content/renderer/media/rtc_video_decoder_bridge_tv.h
@@ -0,0 +1,73 @@
+// Copyright (c) 2013 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.
+
+#ifndef CONTENT_RENDERER_MEDIA_RTC_VIDEO_DECODER_BRIDGE_TV_H_
+#define CONTENT_RENDERER_MEDIA_RTC_VIDEO_DECODER_BRIDGE_TV_H_
+
+#include "base/basictypes.h"
+#include "base/message_loop_proxy.h"
+#include "content/common/content_export.h"
+#include "media/base/audio_decoder_config.h"
+#include "media/base/decoder_buffer_queue.h"
+#include "media/base/demuxer.h"
+#include "media/base/demuxer_stream.h"
+#include "media/base/pipeline_status.h"
+#include "media/base/video_decoder_config.h"
+#include "third_party/webrtc/modules/video_coding/codecs/interface/video_codec_interface.h"
+
+namespace content {
+
+class MediaStreamDependencyFactory;
+
+// A singleton object shared between WebMediaPlayerAndroid and WebRTC Video
+// Engine. Note that this class provides the first remote stream.
+//
+// Example use case:
+//
+// MediaStreamDependencyFactory* tag = ...;
+//
+// // Before using the object:
+// if (!RTCVideoDecoderBridgeTv::Get()->AcquireOwnership(tag))
+//   return;
+//
+// media::Demuxer* demuxer = RTCVideoDecoderBridgeTv::Get()->CreateDemuxer(
+//     tag, base::MessageLoopProxy::current());
+// if (demuxer) {
+//   // use |demuxer|.
+// }
+//
+// // When done using the object:
+// // NOTE: the order is not significant.

[Ami GONE FROM CHROMIUM, 2013/05/08 20:26:44]

Then why not make ReleaseOwnership implicitly call DestroyDemuxer?

[wonsik, 2013/05/13 14:03:48]

Obsolete after redesign

+// RTCVideoDecoderBridgeTv::Get()->DestroyDemuxer(demuxer);
+// RTCVideoDecoderBridgeTv::Get()->ReleaseOwnership(tag);
+class CONTENT_EXPORT RTCVideoDecoderBridgeTv
+    : NON_EXPORTED_BASE(public webrtc::VideoDecoder) {
+ public:
+  // Get RTCVideoDecoderBridgeTv singleton object. If it was not set
+  // before, new default instance will be created.
+  static RTCVideoDecoderBridgeTv* Get();
+
+  // Returns a demuxer object if this is not owned or owned by the same
+  // media_stream_dependency_factory.
+  virtual media::Demuxer* CreateDemuxer(
+      const MediaStreamDependencyFactory* media_stream_dependency_factory,

[Ami GONE FROM CHROMIUM, 2013/05/08 20:26:44]

I'm still pretty unhappy about this business with the singleton that magically
knows who it wants to talk to based on an address (therefore brittle to delete
followed by new reusing the same address).  Singletons are bad enough, but this
pattern unnecessarily bleeds that singletonness into multiple classes' public
APIs.


ISTM this ought to work by having RVI::createMediaPlayer (or WMPA's ctor)
acquire the singleton factory (or NULL if unavailable) and then pass it through
to the downstream deps that need it.  It'll probably mean widening some of the
APIs (like RenderThreadImpl::GetMediaStreamDependencyFactory()) with an
additional parameter, but that seems much more reasonable/readable/robust to me.
 Am I missing something?

[wonsik, 2013/05/13 14:03:48]

Redesigned following your advice.

+      const scoped_refptr<base::MessageLoopProxy>& message_loop) = 0;
+
+  // Destroys the demuxer, owned by this object.
+  virtual void DestroyDemuxer(const media::Demuxer* demuxer) = 0;
+
+  // Returns true if acquired the ownership of this object successfully. One
+  // should acquire ownership before using the object, and can't use the object
+  // if this method fails.
+  virtual bool AcquireOwnership(
+      const MediaStreamDependencyFactory* media_stream_dependency_factory) = 0;
+
+  // Releases ownership of this object.
+  virtual void ReleaseOwnership(
+      const MediaStreamDependencyFactory* media_stream_dependency_factory) = 0;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_MEDIA_RTC_VIDEO_DECODER_BRIDGE_TV_H_