Use FF_THREAD_SLICE threading mode in FFmpeg for MediaSource streams.

media/filters/ffmpeg_video_decoder.h

 // 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.
 
 #ifndef MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_
 #define MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_
 
 #include <list>
 
 #include "base/callback.h"
@@ skipping 11 matching lines @@
 }
 
 namespace media {
 
 class DecoderBuffer;
 class ScopedPtrAVFreeContext;
 class ScopedPtrAVFreeFrame;
 
 class MEDIA_EXPORT FFmpegVideoDecoder : public VideoDecoder {
  public:
-  explicit FFmpegVideoDecoder(
-      const scoped_refptr<base::SingleThreadTaskRunner>& task_runner);
+  // Threading mode determines how frames should be distributed between
+  // decoding threads.
+  enum ThreadingMode {
+    // Each thread decode a single frame and multiple frames may be decoded in

[Ami GONE FROM CHROMIUM, 2014/01/28 07:17:10]

s/decode/decodes/

+    // parallel. In this mode FFmpeg will delay N-1 frames when using N threads.
+    THREADING_FRAME,
+
+    // Each frame is distributed between decode threads. If the video contains
+    // only one slice per frame then only one thread will be used for decoding.
+    THREADING_SLICE,
+  };
+
+  FFmpegVideoDecoder(
+      const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+      ThreadingMode threading_mode);
   virtual ~FFmpegVideoDecoder();
 
   // VideoDecoder implementation.
   virtual void Initialize(const VideoDecoderConfig& config,
                           const PipelineStatusCB& status_cb) OVERRIDE;
   virtual void Decode(const scoped_refptr<DecoderBuffer>& buffer,
                       const DecodeCB& decode_cb) OVERRIDE;
   virtual void Reset(const base::Closure& closure) OVERRIDE;
   virtual void Stop(const base::Closure& closure) OVERRIDE;
 
@@ skipping 21 matching lines @@
   bool ConfigureDecoder();
 
   // Releases resources associated with |codec_context_| and |av_frame_|
   // and resets them to NULL.
   void ReleaseFFmpegResources();
 
   // Reset decoder and call |reset_cb_|.
   void DoReset();
 
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
+  ThreadingMode threading_mode_;
+
   base::WeakPtrFactory<FFmpegVideoDecoder> weak_factory_;
   base::WeakPtr<FFmpegVideoDecoder> weak_this_;
 
   DecoderState state_;
 
   DecodeCB decode_cb_;
   base::Closure reset_cb_;
 
   // FFmpeg structures owned by this object.
   scoped_ptr_malloc<AVCodecContext, ScopedPtrAVFreeContext> codec_context_;
   scoped_ptr_malloc<AVFrame, ScopedPtrAVFreeFrame> av_frame_;
 
   VideoDecoderConfig config_;
 
   VideoFramePool frame_pool_;
 
   DISALLOW_COPY_AND_ASSIGN(FFmpegVideoDecoder);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_