Implement core of compliant MediaSource coded frame processing

media/filters/frame_processor.h

+// Copyright 2014 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_FRAME_PROCESSOR_H_
+#define MEDIA_FILTERS_FRAME_PROCESSOR_H_
+
+#include "base/basictypes.h"
+#include "base/callback_forward.h"
+#include "base/time/time.h"
+#include "media/base/media_export.h"
+#include "media/base/stream_parser.h"
+#include "media/filters/frame_processor_base.h"
+
+namespace media {
+
+// Helper class that implements Media Source Extension's coded frame processing
+// algorithm.
+class MEDIA_EXPORT FrameProcessor : public FrameProcessorBase {
+ public:
+  typedef base::Callback<void(base::TimeDelta)> UpdateDurationCB;
+  explicit FrameProcessor(const UpdateDurationCB& update_duration_cb);
+  virtual ~FrameProcessor();
+
+  // FrameProcessorBase implementation
+  virtual void SetSequenceMode(bool sequence_mode) OVERRIDE;
+  virtual void SetGroupStartTimestampIfInSequenceMode(
+      base::TimeDelta timestamp_offset) OVERRIDE;
+  virtual bool ProcessFrames(const StreamParser::BufferQueue& audio_buffers,
+                             const StreamParser::BufferQueue& video_buffers,
+                             const StreamParser::TextBufferQueueMap& text_map,
+                             base::TimeDelta append_window_start,
+                             base::TimeDelta append_window_end,
+                             bool* new_media_segment,
+                             base::TimeDelta* timestamp_offset) OVERRIDE;
+
+ private:
+  // Helper that processes one frame with the coded frame processing algorithm.
+  // Returns false on error or true on success.
+  bool ProcessFrame(scoped_refptr<StreamParserBuffer> frame,
+                    base::TimeDelta append_window_start,
+                    base::TimeDelta append_window_end,
+                    base::TimeDelta* timestamp_offset,
+                    bool* new_media_segment);
+
+  // Sets the need random access point flag on all track buffers to true.
+  void SetAllTrackBuffersNeedRandomAccessPoint();
+
+  // Tracks the MSE coded frame processing variable of same name.
+  // Its value is meaningless if |group_start_timestamp_set_| is false.
+  // |group_start_timestamp_set_| is initialized to false.
+  base::TimeDelta group_start_timestamp_;
+  bool group_start_timestamp_set_;
+
+  // Tracks the MSE coded frame processing variable of same name. It stores the
+  // highest presentation end timestamp encountered in the current coded frame
+  // group. It is set to 0 when the assocated SourceBuffer is created and gets
+  // updated by ProcessFrames().
+  base::TimeDelta highest_presentation_end_timestamp_;
+
+  UpdateDurationCB update_duration_cb_;
+
+  DISALLOW_COPY_AND_ASSIGN(FrameProcessor);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_FILTERS_FRAME_PROCESSOR_H_