Revert 259154 "Remove HasAudio(), HasVideo(), GetInitialNaturalS..."

trunk/src/media/base/pipeline.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_BASE_PIPELINE_H_
 #define MEDIA_BASE_PIPELINE_H_
 
 #include <string>
 
 #include "base/gtest_prod_util.h"
@@ skipping 16 matching lines @@
 
 namespace media {
 
 class Clock;
 class FilterCollection;
 class MediaLog;
 class TextRenderer;
 class TextTrackConfig;
 class VideoRenderer;
 
-// Metadata describing a pipeline once it has been initialized.
-struct PipelineMetadata {
-  PipelineMetadata() : has_audio(false), has_video(false) {}
-
-  bool has_audio;
-  bool has_video;
-  gfx::Size natural_size;
-};
-
-typedef base::Callback<void(PipelineMetadata)> PipelineMetadataCB;
-
 // Pipeline runs the media pipeline.  Filters are created and called on the
 // task runner injected into this object. Pipeline works like a state
 // machine to perform asynchronous initialization, pausing, seeking and playing.
 //
 // Here's a state diagram that describes the lifetime of this object.
 //
 //   [ *Created ]                       [ Any State ]
 //         | Start()                         | Stop() / SetError()
 //         V                                 V
 //   [ InitXXX (for each filter) ]      [ Stopping ]
@@ skipping 13 matching lines @@
 // completed, we are implicitly in a "Paused" state.  At that point we simulate
 // a Seek() to the beginning of the media to give filters a chance to preroll.
 // From then on the normal Seek() transitions are carried out and we start
 // playing the media.
 //
 // If any error ever happens, this object will transition to the "Error" state
 // from any state. If Stop() is ever called, this object will transition to
 // "Stopped" state.
 class MEDIA_EXPORT Pipeline : public DemuxerHost {
  public:
+  // Buffering states the pipeline transitions between during playback.
+  // kHaveMetadata:
+  //   Indicates that the following things are known:
+  //   content duration, container video size, start time, and whether the
+  //   content has audio and/or video in supported formats.
+  // kPrerollCompleted:
+  //   All renderers have buffered enough data to satisfy preroll and are ready
+  //   to start playback.
+  enum BufferingState {
+    kHaveMetadata,
+    kPrerollCompleted,
+  };
+
+  typedef base::Callback<void(BufferingState)> BufferingStateCB;
+
   // Constructs a media pipeline that will execute on |task_runner|.
   Pipeline(const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
            MediaLog* media_log);
   virtual ~Pipeline();
 
   // Build a pipeline to using the given filter collection to construct a filter
   // chain, executing |seek_cb| when the initial seek/preroll has completed.
   //
   // |filter_collection| must be a complete collection containing a demuxer,
   // audio/video decoders, and audio/video renderers. Failing to do so will
   // result in a crash.
   //
   // The following permanent callbacks will be executed as follows up until
   // Stop() has completed:
   //   |ended_cb| will be executed whenever the media reaches the end.
-  //   |error_cb| will be executed whenever an error occurs but hasn't been
-  //              reported already through another callback.
-  //   |metadata_cb| will be executed when the content duration, container video
-  //                 size, start time, and whether the content has audio and/or
-  //                 video in supported formats are known.
-  //   |preroll_completed_cb| will be executed when all renderers have buffered
-  //                          enough data to satisfy preroll and are ready to
-  //                          start playback.
-  //   |duration_change_cb| optional callback that will be executed whenever the
+  //   |error_cb| will be executed whenever an error occurs but hasn't
+  //              been reported already through another callback.
+  //   |buffering_state_cb| Optional callback that will be executed whenever the
+  //                    pipeline's buffering state changes.
+  //   |duration_change_cb| Optional callback that will be executed whenever the
   //                        presentation duration changes.
   // It is an error to call this method after the pipeline has already started.
   void Start(scoped_ptr<FilterCollection> filter_collection,
              const base::Closure& ended_cb,
              const PipelineStatusCB& error_cb,
              const PipelineStatusCB& seek_cb,
-             const PipelineMetadataCB& metadata_cb,
-             const base::Closure& preroll_completed_cb,
+             const BufferingStateCB& buffering_state_cb,
              const base::Closure& duration_change_cb);
 
   // Asynchronously stops the pipeline, executing |stop_cb| when the pipeline
   // teardown has completed.
   //
   // Stop() must complete before destroying the pipeline. It it permissible to
   // call Stop() at any point during the lifetime of the pipeline.
   //
   // It is safe to delete the pipeline during the execution of |stop_cb|.
   void Stop(const base::Closure& stop_cb);
 
   // Attempt to seek to the position specified by time.  |seek_cb| will be
   // executed when the all filters in the pipeline have processed the seek.
   //
   // Clients are expected to call GetMediaTime() to check whether the seek
   // succeeded.
   //
   // It is an error to call this method if the pipeline has not started.
   void Seek(base::TimeDelta time, const PipelineStatusCB& seek_cb);
 
   // Returns true if the pipeline has been started via Start().  If IsRunning()
   // returns true, it is expected that Stop() will be called before destroying
   // the pipeline.
   bool IsRunning() const;
 
+  // Returns true if the media has audio.
+  bool HasAudio() const;
+
+  // Returns true if the media has video.
+  bool HasVideo() const;
+
   // Gets the current playback rate of the pipeline.  When the pipeline is
   // started, the playback rate will be 0.0f.  A rate of 1.0f indicates
   // that the pipeline is rendering the media at the standard rate.  Valid
   // values for playback rate are >= 0.0f.
   float GetPlaybackRate() const;
 
   // Attempt to adjust the playback rate. Setting a playback rate of 0.0f pauses
   // all rendering of the media.  A rate of 1.0f indicates a normal playback
   // rate.  Values for the playback rate must be greater than or equal to 0.0f.
   //
@@ skipping 18 matching lines @@
   Ranges<base::TimeDelta> GetBufferedTimeRanges();
 
   // Get the duration of the media in microseconds.  If the duration has not
   // been determined yet, then returns 0.
   base::TimeDelta GetMediaDuration() const;
 
   // Get the total size of the media file.  If the size has not yet been
   // determined or can not be determined, this value is 0.
   int64 GetTotalBytes() const;
 
+  // Get the video's initial natural size as reported by the container. Note
+  // that the natural size can change during playback.
+  gfx::Size GetInitialNaturalSize() const;
+
   // Return true if loading progress has been made since the last time this
   // method was called.
   bool DidLoadingProgress() const;
 
   // Gets the current pipeline statistics.
   PipelineStatistics GetStatistics() const;
 
   void SetClockForTesting(Clock* clock);
   void SetErrorForTesting(PipelineStatus status);
 
@@ skipping 60 matching lines @@
 
   // Callback executed by audio renderer to update clock time.
   void OnAudioTimeUpdate(base::TimeDelta time, base::TimeDelta max_time);
 
   // Callback executed by video renderer to update clock time.
   void OnVideoTimeUpdate(base::TimeDelta max_time);
 
   // The following "task" methods correspond to the public methods, but these
   // methods are run as the result of posting a task to the Pipeline's
   // task runner.
-  void StartTask();
+  void StartTask(scoped_ptr<FilterCollection> filter_collection,
+                 const base::Closure& ended_cb,
+                 const PipelineStatusCB& error_cb,
+                 const PipelineStatusCB& seek_cb,
+                 const BufferingStateCB& buffering_state_cb,
+                 const base::Closure& duration_change_cb);
 
   // Stops and destroys all filters, placing the pipeline in the kStopped state.
   void StopTask(const base::Closure& stop_cb);
 
   // Carries out stopping and destroying all filters, placing the pipeline in
   // the kStopped state.
   void ErrorChangedTask(PipelineStatus error);
 
   // Carries out notifying filters that the playback rate has changed.
   void PlaybackRateChangedTask(float playback_rate);
@@ skipping 82 matching lines @@
   Ranges<int64> buffered_byte_ranges_;
   Ranges<base::TimeDelta> buffered_time_ranges_;
 
   // True when AddBufferedByteRange() has been called more recently than
   // DidLoadingProgress().
   mutable bool did_loading_progress_;
 
   // Total size of the media.  Set by filters.
   int64 total_bytes_;
 
+  // The initial natural size of the video as reported by the container.
+  gfx::Size initial_natural_size_;
+
   // Current volume level (from 0.0f to 1.0f).  This value is set immediately
   // via SetVolume() and a task is dispatched on the task runner to notify the
   // filters.
   float volume_;
 
   // Current playback rate (>= 0.0f).  This value is set immediately via
   // SetPlaybackRate() and a task is dispatched on the task runner to notify
   // the filters.
   float playback_rate_;
 
   // base::TickClock used by |clock_|.
   base::DefaultTickClock default_tick_clock_;
 
   // Reference clock.  Keeps track of current playback time.  Uses system
   // clock and linear interpolation, but can have its time manually set
   // by filters.
   scoped_ptr<Clock> clock_;
 
   // If this value is set to true, then |clock_| is paused and we are waiting
   // for an update of the clock greater than or equal to the elapsed time to
   // start the clock.
   bool waiting_for_clock_update_;
 
   // Status of the pipeline.  Initialized to PIPELINE_OK which indicates that
   // the pipeline is operating correctly. Any other value indicates that the
   // pipeline is stopped or is stopping.  Clients can call the Stop() method to
   // reset the pipeline state, and restore this to PIPELINE_OK.
   PipelineStatus status_;
 
+  // Whether the media contains rendered audio or video streams.
+  // TODO(fischman,scherkus): replace these with checks for
+  // {audio,video}_decoder_ once extraction of {Audio,Video}Decoder from the
+  // Filter heirarchy is done.
+  bool has_audio_;
+  bool has_video_;
+
   // The following data members are only accessed by tasks posted to
   // |task_runner_|.
 
   // Member that tracks the current state.
   State state_;
 
   // Whether we've received the audio/video/text ended events.
   bool audio_ended_;
   bool video_ended_;
   bool text_ended_;
 
   // Set to true in DisableAudioRendererTask().
   bool audio_disabled_;
 
   // Temporary callback used for Start() and Seek().
   PipelineStatusCB seek_cb_;
 
   // Temporary callback used for Stop().
   base::Closure stop_cb_;
 
   // Permanent callbacks passed in via Start().
   base::Closure ended_cb_;
   PipelineStatusCB error_cb_;
-  PipelineMetadataCB metadata_cb_;
-  base::Closure preroll_completed_cb_;
+  BufferingStateCB buffering_state_cb_;
   base::Closure duration_change_cb_;
 
   // Contains the demuxer and renderers to use when initializing.
   scoped_ptr<FilterCollection> filter_collection_;
 
   // Holds the initialized demuxer. Used for seeking. Owned by client.
   Demuxer* demuxer_;
 
   // Holds the initialized renderers. Used for setting the volume,
   // playback rate, and determining when playback has finished.
@@ skipping 10 matching lines @@
   scoped_ptr<SerialRunner> pending_callbacks_;
 
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(Pipeline);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_PIPELINE_H_