content/browser/media/capture/web_contents_audio_input_stream.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 // An AudioInputStream which provides a loop-back of all audio output generated
   6 // by the entire RenderFrame tree associated with a WebContents instance.  The
   7 // single stream of data is produced by format-converting and mixing all audio
   8 // output streams.  As the RenderFrameHost tree mutates (e.g., due to page
   9 // navigations, or crashes/reloads), the stream will continue without
  10 // interruption.  In other words, WebContentsAudioInputStream provides tab-level
  11 // audio mirroring.
  12
  13 #ifndef CONTENT_BROWSER_MEDIA_CAPTURE_WEB_CONTENTS_AUDIO_INPUT_STREAM_H_
  14 #define CONTENT_BROWSER_MEDIA_CAPTURE_WEB_CONTENTS_AUDIO_INPUT_STREAM_H_
  15
  16 #include <string>
  17
  18 #include "base/memory/ref_counted.h"
  19 #include "content/common/content_export.h"
  20 #include "media/audio/audio_io.h"
  21
  22 namespace base {
  23 class SingleThreadTaskRunner;
  24 }
  25
  26 namespace media {
  27 class AudioParameters;
  28 class VirtualAudioInputStream;
  29 }
  30
  31 namespace content {
  32
  33 class AudioMirroringManager;
  34 class WebContentsTracker;
  35
  36 class CONTENT_EXPORT WebContentsAudioInputStream
  37     : NON_EXPORTED_BASE(public media::AudioInputStream) {
  38  public:
  39   // media::AudioInputStream implementation
  40   bool Open() override;
  41   void Start(AudioInputCallback* callback) override;
  42   void Stop() override;
  43   void Close() override;
  44   double GetMaxVolume() override;
  45   void SetVolume(double volume) override;
  46   double GetVolume() override;
  47   bool SetAutomaticGainControl(bool enabled) override;
  48   bool GetAutomaticGainControl() override;
  49   bool IsMuted() override;
  50
  51   // Create a new audio mirroring session, or return NULL on error.  |device_id|
  52   // should be in the format accepted by
  53   // WebContentsCaptureUtil::ExtractTabCaptureTarget().  The caller must
  54   // guarantee Close() is called on the returned object so that it may
  55   // self-destruct.
  56   // |worker_task_runner| is the task runner on which AudioInputCallback methods
  57   // are called and may or may not be the single thread that invokes the
  58   // AudioInputStream methods.
  59   static WebContentsAudioInputStream* Create(
  60       const std::string& device_id,
  61       const media::AudioParameters& params,
  62       const scoped_refptr<base::SingleThreadTaskRunner>& worker_task_runner,
  63       AudioMirroringManager* audio_mirroring_manager);
  64
  65  private:
  66   friend class WebContentsAudioInputStreamTest;
  67
  68   // Maintain most state and functionality in an internal ref-counted
  69   // implementation class.  This object must outlive a call to Close(), until
  70   // the shutdown tasks running on other threads complete: The
  71   // AudioMirroringManager on the IO thread, the WebContentsTracker on the UI
  72   // thread, and the VirtualAudioOuputStreams on the audio thread.
  73   class Impl;
  74
  75   WebContentsAudioInputStream(
  76       int render_process_id, int main_render_frame_id,
  77       AudioMirroringManager* mirroring_manager,
  78       const scoped_refptr<WebContentsTracker>& tracker,
  79       media::VirtualAudioInputStream* mixer_stream);
  80
  81   ~WebContentsAudioInputStream() override;
  82
  83   scoped_refptr<Impl> impl_;
  84
  85   DISALLOW_COPY_AND_ASSIGN(WebContentsAudioInputStream);
  86 };
  87
  88 }  // namespace content
  89
  90 #endif  // CONTENT_BROWSER_MEDIA_CAPTURE_WEB_CONTENTS_AUDIO_INPUT_STREAM_H_