media/base/demuxer.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef MEDIA_BASE_DEMUXER_H_
   6 #define MEDIA_BASE_DEMUXER_H_
   7
   8 #include "base/memory/ref_counted.h"
   9 #include "base/time.h"
  10 #include "media/base/data_source.h"
  11 #include "media/base/demuxer_stream.h"
  12 #include "media/base/media_export.h"
  13 #include "media/base/pipeline_status.h"
  14
  15 namespace media {
  16
  17 class MEDIA_EXPORT DemuxerHost : public DataSourceHost {
  18  public:
  19   virtual ~DemuxerHost();
  20
  21   // Sets the duration of the media in microseconds.
  22   // Duration may be kInfiniteDuration() if the duration is not known.
  23   virtual void SetDuration(base::TimeDelta duration) = 0;
  24
  25   // Sets the byte offset at which the client is requesting the video.
  26   virtual void SetCurrentReadPosition(int64 offset) = 0;
  27
  28   // Stops execution of the pipeline due to a fatal error.  Do not call this
  29   // method with PIPELINE_OK.
  30   virtual void OnDemuxerError(PipelineStatus error) = 0;
  31 };
  32
  33 class MEDIA_EXPORT Demuxer : public base::RefCountedThreadSafe<Demuxer> {
  34  public:
  35   Demuxer();
  36
  37   // Completes initialization of the demuxer.
  38   //
  39   // The demuxer does not own |host| as it is guaranteed to outlive the
  40   // lifetime of the demuxer. Don't delete it!
  41   virtual void Initialize(DemuxerHost* host,
  42                           const PipelineStatusCB& status_cb) = 0;
  43
  44   // The pipeline playback rate has been changed.  Demuxers may implement this
  45   // method if they need to respond to this call.
  46   virtual void SetPlaybackRate(float playback_rate);
  47
  48   // Carry out any actions required to seek to the given time, executing the
  49   // callback upon completion.
  50   virtual void Seek(base::TimeDelta time, const PipelineStatusCB& status_cb);
  51
  52   // The pipeline is being stopped either as a result of an error or because
  53   // the client called Stop().
  54   virtual void Stop(const base::Closure& callback);
  55
  56   // This method is called from the pipeline when the audio renderer
  57   // is disabled. Demuxers can ignore the notification if they do not
  58   // need to react to this event.
  59   //
  60   // TODO(acolwell): Change to generic DisableStream(DemuxerStream::Type).
  61   virtual void OnAudioRendererDisabled();
  62
  63   // Returns the given stream type, or NULL if that type is not present.
  64   virtual scoped_refptr<DemuxerStream> GetStream(DemuxerStream::Type type) = 0;
  65
  66   // Returns the starting time for the media file.
  67   virtual base::TimeDelta GetStartTime() const = 0;
  68
  69   // Returns the content bitrate. May be obtained from container or
  70   // approximated. Returns 0 if it is unknown.
  71   virtual int GetBitrate() = 0;
  72
  73  protected:
  74   friend class base::RefCountedThreadSafe<Demuxer>;
  75   virtual ~Demuxer();
  76
  77  private:
  78   DISALLOW_COPY_AND_ASSIGN(Demuxer);
  79 };
  80
  81 }  // namespace media
  82
  83 #endif  // MEDIA_BASE_DEMUXER_H_