Move Liveness from DemuxerStreamProvider to DemuxerStream.

media/filters/video_renderer_impl.cc

 // Copyright 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.
 
 #include "media/filters/video_renderer_impl.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/callback_helpers.h"
 #include "base/debug/trace_event.h"
@@ skipping 89 matching lines @@
   DCHECK(!pending_read_);
   DCHECK(ready_frames_.empty());
   DCHECK_EQ(buffering_state_, BUFFERING_HAVE_NOTHING);
 
   state_ = kPlaying;
   start_timestamp_ = timestamp;
   AttemptRead_Locked();
 }
 
 void VideoRendererImpl::Initialize(DemuxerStream* stream,
-                                   bool low_delay,
                                    const PipelineStatusCB& init_cb,
                                    const StatisticsCB& statistics_cb,
                                    const BufferingStateCB& buffering_state_cb,
                                    const base::Closure& ended_cb,
                                    const PipelineStatusCB& error_cb,
                                    const TimeDeltaCB& get_time_cb) {
   DCHECK(task_runner_->BelongsToCurrentThread());
   base::AutoLock auto_lock(lock_);
   DCHECK(stream);
   DCHECK_EQ(stream->type(), DemuxerStream::VIDEO);
   DCHECK(!init_cb.is_null());
   DCHECK(!statistics_cb.is_null());
   DCHECK(!buffering_state_cb.is_null());
   DCHECK(!ended_cb.is_null());
   DCHECK(!get_time_cb.is_null());
   DCHECK_EQ(kUninitialized, state_);
 
-  low_delay_ = low_delay;
+  low_delay_ = (stream->liveness() == DemuxerStream::LIVENESS_LIVE);

[wolenetz, 2014/11/11 23:48:07]

nit: This logic is now in multiple places (see also
DecoderStreamTraits<DemuxerStream::VIDEO>::InitializeDecoder(), and inverse in
VideoRendererImplTest::CallInitialize()). Can some of this be simplified (maybe
as a static method in DemuxerStream such as:
static bool is_low_delay(Liveness liveness) { return liveness == LIVENESS_LIVE;
} ) ?

[xhwang, 2014/11/14 06:38:04]

Hmm, I don't feel

DemuxerStream::is_low_delay(stream->liveness)

is much better than 

stream->liveness() == DemuxerStream::LIVENESS_LIVE

Maybe we don't need liveness at all in DemuxerStream. A boolean "low_delay"
would suffice.

I'll like to iterate on this later.

[wolenetz, 2014/11/14 19:21:58]

Acknowledged.

 
   // Always post |init_cb_| because |this| could be destroyed if initialization
   // failed.
   init_cb_ = BindToCurrentLoop(init_cb);
 
   statistics_cb_ = statistics_cb;
   buffering_state_cb_ = buffering_state_cb;
   ended_cb_ = ended_cb;
   error_cb_ = error_cb;
   get_time_cb_ = get_time_cb;
   state_ = kInitializing;
 
   video_frame_stream_->Initialize(
-      stream,
-      low_delay,
-      statistics_cb,
+      stream, statistics_cb,
       base::Bind(&VideoRendererImpl::OnVideoFrameStreamInitialized,
                  weak_factory_.GetWeakPtr()));
 }
 
 void VideoRendererImpl::OnVideoFrameStreamInitialized(bool success) {
   DCHECK(task_runner_->BelongsToCurrentThread());
   base::AutoLock auto_lock(lock_);
   DCHECK_EQ(state_, kInitializing);
 
   if (!success) {
@@ skipping 286 matching lines @@
     task_runner_->PostTask(FROM_HERE, base::Bind(statistics_cb_, statistics));
 
     frames_decoded_ = 0;
     frames_dropped_ = 0;
   }
 
   frame_available_.TimedWait(wait_duration);
 }
 
 }  // namespace media