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 RenderView associated with a WebContents instance. The single stream 7 // of data is produced by format-converting and mixing all audio output from a 8 // RenderView. In other words, WebContentsAudioInputStream provides tab-level 9 // audio mirroring. 10 // 11 // The implementation observes a WebContents instance (which represents a 12 // browser tab) so that it can track the replacement of RenderViews due to 13 // navigation, crash/reload, etc. events; and take appropriate actions to 14 // provide a seamless, uninterrupted mirroring experience. 15 16 #ifndef CONTENT_BROWSER_RENDERER_HOST_MEDIA_WEB_CONTENTS_AUDIO_INPUT_STREAM_H_ 17 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_WEB_CONTENTS_AUDIO_INPUT_STREAM_H_ 18 19 #include <string> 20 21 #include "base/memory/ref_counted.h" 22 #include "content/common/content_export.h" 23 #include "media/audio/audio_io.h" 24 25 namespace base { 26 class MessageLoopProxy; 27 } 28 29 namespace media { 30 class AudioParameters; 31 class VirtualAudioInputStream; 32 } 33 34 namespace content { 35 36 class AudioMirroringManager; 37 class WebContentsTracker; 38 39 class CONTENT_EXPORT WebContentsAudioInputStream 40 : NON_EXPORTED_BASE(public media::AudioInputStream) { 41 public: 42 // media::AudioInputStream implementation 43 virtual bool Open() OVERRIDE; 44 virtual void Start(AudioInputCallback* callback) OVERRIDE; 45 virtual void Stop() OVERRIDE; 46 virtual void Close() OVERRIDE; 47 virtual double GetMaxVolume() OVERRIDE; 48 virtual void SetVolume(double volume) OVERRIDE; 49 virtual double GetVolume() OVERRIDE; 50 virtual void SetAutomaticGainControl(bool enabled) OVERRIDE; 51 virtual bool GetAutomaticGainControl() OVERRIDE; 52 53 // Create a new audio mirroring session, or return NULL on error. |device_id| 54 // should be in the format accepted by 55 // WebContentsCaptureUtil::ExtractTabCaptureTarget(). The caller must 56 // guarantee Close() is called on the returned object so that it may 57 // self-destruct. 58 // |worker_loop| is the loop on which AudioInputCallback methods are called 59 // and may or may not be the single thread that invokes the AudioInputStream 60 // methods. 61 static WebContentsAudioInputStream* Create( 62 const std::string& device_id, 63 const media::AudioParameters& params, 64 const scoped_refptr<base::MessageLoopProxy>& worker_loop, 65 AudioMirroringManager* audio_mirroring_manager); 66 67 private: 68 friend class WebContentsAudioInputStreamTest; 69 70 // Maintain most state and functionality in an internal ref-counted 71 // implementation class. This object must outlive a call to Close(), until 72 // the shutdown tasks running on other threads complete: The 73 // AudioMirroringManager on the IO thread, the WebContentsTracker on the UI 74 // thread, and the VirtualAudioOuputStreams on the audio thread. 75 class Impl; 76 77 WebContentsAudioInputStream( 78 int render_process_id, int render_view_id, 79 AudioMirroringManager* mirroring_manager, 80 const scoped_refptr<WebContentsTracker>& tracker, 81 media::VirtualAudioInputStream* mixer_stream); 82 83 virtual ~WebContentsAudioInputStream(); 84 85 scoped_refptr<Impl> impl_; 86 87 DISALLOW_COPY_AND_ASSIGN(WebContentsAudioInputStream); 88 }; 89 90 } // namespace content 91 92 #endif // CONTENT_BROWSER_RENDERER_HOST_MEDIA_WEB_CONTENTS_AUDIO_INPUT_STREAM_H_ 93
