Adding ChunkDemuxer implementation.

media/filters/chunk_demuxer.h

+// 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.
+
+#ifndef MEDIA_FILTERS_CHUNK_DEMUXER_H_
+#define MEDIA_FILTERS_CHUNK_DEMUXER_H_
+
+#include <list>
+
+#include "base/synchronization/lock.h"
+#include "media/base/filters.h"
+#include "media/webm/webm_cluster_parser.h"
+
+struct AVFormatContext;
+
+namespace media {
+
+class ChunkDemuxerStream;
+
+// Demuxer implementation that allows chunks of WebM media data to be passed
+// from JavaScript to the media stack.
+class ChunkDemuxer : public Demuxer {
+ public:
+  ChunkDemuxer();
+  virtual ~ChunkDemuxer();
+
+  bool Init(const uint8* data, int size);
+
+  // Filter implementation.
+  virtual void set_host(FilterHost* filter_host);
+  virtual void Stop(FilterCallback* callback);
+  virtual void Seek(base::TimeDelta time, const FilterStatusCB&  cb);
+  virtual void OnAudioRendererDisabled();
+  virtual void SetPreload(Preload preload);
+
+  // Demuxer implementation.
+  virtual scoped_refptr<DemuxerStream> GetStream(DemuxerStream::Type type);
+  virtual base::TimeDelta GetStartTime() const;
+
+  // Methods used by MediaDataSink
+  void FlushData();
+  bool AddData(const uint8* data, unsigned length);
+  void Shutdown();
+
+ private:
+  enum State {
+    WAITING_FOR_INIT,
+    INITIALIZED,
+    INIT_ERROR,
+    SHUTDOWN,
+  };
+
+  void ChangeState(State new_state);
+
+  // Generates an AVFormatContext for the INFO & TRACKS elements contained
+  // in |data|. Returns NULL if parsing |data| fails.
+  AVFormatContext* CreateFormatContext(const uint8* data, int size) const;
+
+  // Sets up |audio_| & |video_| DemuxerStreams based on the data in
+  // |format_context_|. Returns false if no valid audio or video stream were
+  // found.
+  bool SetupStreams();
+
+  // Parse all the buffers in |pending_buffers_|. Returns false if parsing one
+  // of the buffers fails.
+  bool ParsePendingBuffers();
+
+  // Parse a buffer that was passed to AddData(). |data| is expected to contain
+  // one or more WebM Clusters. Returns false if parsing the data fails.
+  bool ParseAndAddData_Locked(const uint8* data, int length);
+
+  base::Lock lock_;
+  State state_;
+
+  FilterStatusCB seek_cb_;
+
+  scoped_refptr<ChunkDemuxerStream> audio_;
+  scoped_refptr<ChunkDemuxerStream> video_;
+
+  AVFormatContext* format_context_;
+
+  int64 buffered_bytes_;
+
+  base::TimeDelta duration_;
+
+  scoped_ptr<WebMClusterParser> cluster_parser_;
+
+  typedef std::list<scoped_refptr<media::Buffer> > BufferList;
+  BufferList pending_buffers_;
+
+  // Should a Seek() call wait for more data before calling the
+  // callback.
+  bool seek_waits_for_data_;
+
+  DISALLOW_COPY_AND_ASSIGN(ChunkDemuxer);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_FILTERS_CHUNK_DEMUXER_H_