media/audio/audio_source_diverter.h

   1 // Copyright (c) 2013 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_AUDIO_AUDIO_SOURCE_DIVERTER_H_
   6 #define MEDIA_AUDIO_AUDIO_SOURCE_DIVERTER_H_
   7
   8 #include "media/base/media_export.h"
   9
  10 // Audio sources may optionally implement AudioSourceDiverter to temporarily
  11 // divert audio data to an alternate AudioOutputStream.  This allows the audio
  12 // data to be plumbed to an alternate consumer; for example, a loopback
  13 // mechanism for audio mirroring.
  14
  15 namespace media {
  16
  17 class AudioOutputStream;
  18 class AudioParameters;
  19
  20 class MEDIA_EXPORT AudioSourceDiverter {
  21 public:
  22   // Returns the audio parameters of the divertable audio data.
  23   virtual const AudioParameters& GetAudioParameters() = 0;
  24
  25   // Start providing audio data to the given |to_stream|, which is in an
  26   // unopened state.  |to_stream| remains under the control of the
  27   // AudioSourceDiverter.
  28   virtual void StartDiverting(AudioOutputStream* to_stream) = 0;
  29
  30   // Stops diverting audio data to the stream.  The AudioSourceDiverter is
  31   // responsible for making sure the stream is closed, perhaps asynchronously.
  32   virtual void StopDiverting() = 0;
  33
  34 protected:
  35   virtual ~AudioSourceDiverter() {}
  36 };
  37
  38 }  // namespace media
  39
  40 #endif  // MEDIA_AUDIO_AUDIO_SOURCE_DIVERTER_H_