Simplify VideoDecodeEngine interface by making everything synchronous.

media/filters/video_renderer_base.cc

 // Copyright (c) 2011 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 "base/bind.h"
 #include "base/callback.h"
 #include "base/threading/platform_thread.h"
 #include "media/base/buffers.h"
 #include "media/base/filter_host.h"
 #include "media/base/limits.h"
@@ skipping 345 matching lines @@
   // frame when this is true.
   frame_available_.Signal();
   if (state_ == kFlushing) {
     FlushBuffers_Locked();
   } else if (state_ == kError || state_ == kStopped) {
     DoStopOrErrorFlush_Locked();
   }
 }
 
 void VideoRendererBase::ConsumeVideoFrame(scoped_refptr<VideoFrame> frame) {
-  if (frame) {
-    PipelineStatistics statistics;
-    statistics.video_frames_decoded = 1;
-    statistics_callback_.Run(statistics);
-  }
+  DCHECK(frame);
+
+  PipelineStatistics statistics;
+  statistics.video_frames_decoded = 1;
+  statistics_callback_.Run(statistics);

[acolwell GONE FROM CHROMIUM, 2011/10/28 17:38:47]

Do we want to include end of stream or empty frames in this count?

[scherkus (not reviewing), 2011/11/01 04:18:26]

Moved below -- also shouldn't the decoder increment this?

 
   base::AutoLock auto_lock(lock_);
 
-  if (!frame) {
-    EnterErrorState_Locked(PIPELINE_ERROR_DECODE);
-    return;
-  }
-
   // Decoder could reach seek state before our Seek() get called.
   // We will enter kSeeking
   if (state_ == kFlushed)
     state_ = kSeeking;
 
   // Synchronous flush between filters should prevent this from happening.
   DCHECK_NE(state_, kStopped);
-  if (frame.get() && !frame->IsEndOfStream())
+  if (!frame->IsEndOfStream())

[acolwell GONE FROM CHROMIUM, 2011/10/28 17:38:47]

Why don't end of stream frames decrement the pending_read_ count? Aren't they
are sult of a read?

[scherkus (not reviewing), 2011/11/01 04:18:26]

Done.

     --pending_reads_;
 
   DCHECK(state_ != kUninitialized && state_ != kStopped && state_ != kError);
 
   if (state_ == kPaused || state_ == kFlushing) {
     // Decoder are flushing rubbish video frame, we will not display them.
-    if (frame.get() && !frame->IsEndOfStream())
+    if (!frame->IsEndOfStream())
       frames_queue_done_.push_back(frame);
     DCHECK_LE(frames_queue_done_.size(),

[acolwell GONE FROM CHROMIUM, 2011/10/28 17:38:47]

Remove this queue. Frame recycling must die.

[scherkus (not reviewing), 2011/11/01 04:18:26]

Done.

               static_cast<size_t>(Limits::kMaxVideoFrames));
 
     // Excluding kPause here, because in pause state, we will never
     // transfer out-bounding buffer. We do not flush buffer when Compositor
     // hold reference to our video frame either.
     if (state_ == kFlushing && pending_paint_ == false)
       FlushBuffers_Locked();
 
     return;
   }
@@ skipping 40 matching lines @@
   } else if (state_ == kFlushing && pending_reads_ == 0 && !pending_paint_) {
     OnFlushDone_Locked();
   }
 
   if (new_frame_available) {
     base::AutoUnlock auto_unlock(lock_);
     OnFrameAvailable();
   }
 }
 
 void VideoRendererBase::ReadInput(scoped_refptr<VideoFrame> frame) {

[acolwell GONE FROM CHROMIUM, 2011/10/28 17:38:47]

Remove frame parameter now that we aren't doing buffer recycling.

[scherkus (not reviewing), 2011/11/01 04:18:26]

Done.

   // We should never return empty frames or EOS frame.
   DCHECK(frame.get() && !frame->IsEndOfStream());
 
   decoder_->ProduceVideoFrame(frame);
   ++pending_reads_;
 }
 
 void VideoRendererBase::ScheduleRead_Locked() {
   lock_.AssertAcquired();
   DCHECK_NE(kEnded, state_);
@@ skipping 122 matching lines @@
 void VideoRendererBase::DoStopOrErrorFlush_Locked() {
   DCHECK(!pending_paint_);
   DCHECK(!pending_paint_with_last_available_);
   lock_.AssertAcquired();
   FlushBuffers_Locked();
   last_available_frame_ = NULL;
   DCHECK_EQ(pending_reads_, 0);
 }
 
 }  // namespace media