Binding media stream audio track to speech recognition [renderer]

content/renderer/speech_recognition_dispatcher.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 CONTENT_RENDERER_SPEECH_RECOGNITION_DISPATCHER_H_
 #define CONTENT_RENDERER_SPEECH_RECOGNITION_DISPATCHER_H_
 
 #include <map>
 
 #include "base/basictypes.h"
+#include "base/memory/shared_memory.h"
+#include "base/message_loop/message_loop_proxy.h"
 #include "content/public/common/speech_recognition_result.h"
 #include "content/public/renderer/render_view_observer.h"
+#include "third_party/WebKit/public/platform/WebMediaStreamTrack.h"
 #include "third_party/WebKit/public/platform/WebVector.h"
 #include "third_party/WebKit/public/web/WebSpeechRecognitionHandle.h"
 #include "third_party/WebKit/public/web/WebSpeechRecognizer.h"
 
+
+namespace media {
+class AudioParameters;
+}
+
 namespace content {
 class RenderViewImpl;
+class SpeechRecognitionAudioSourceProvider;
 struct SpeechRecognitionError;
 struct SpeechRecognitionResult;
 
 // SpeechRecognitionDispatcher is a delegate for methods used by WebKit for
 // scripted JS speech APIs. It's the complement of
 // SpeechRecognitionDispatcherHost (owned by RenderViewHost).
 class SpeechRecognitionDispatcher : public RenderViewObserver,
                                     public blink::WebSpeechRecognizer {
  public:
   explicit SpeechRecognitionDispatcher(RenderViewImpl* render_view);
   virtual ~SpeechRecognitionDispatcher();
 
   // Aborts all speech recognitions.
   void AbortAllRecognitions();
 
  private:
   // RenderViewObserver implementation.
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 
   // blink::WebSpeechRecognizer implementation.
+  virtual void attach(const blink::WebSpeechRecognitionHandle&,
+                             const blink::WebMediaStreamTrack&,
+                             blink::WebSpeechRecognizerClient*) OVERRIDE;
+  virtual void detach(const blink::WebSpeechRecognitionHandle&,
+                             blink::WebSpeechRecognizerClient*) OVERRIDE;
   virtual void start(const blink::WebSpeechRecognitionHandle&,
                      const blink::WebSpeechRecognitionParams&,
                      blink::WebSpeechRecognizerClient*) OVERRIDE;
   virtual void stop(const blink::WebSpeechRecognitionHandle&,
                     blink::WebSpeechRecognizerClient*) OVERRIDE;
   virtual void abort(const blink::WebSpeechRecognitionHandle&,
                      blink::WebSpeechRecognizerClient*) OVERRIDE;
 
   void OnRecognitionStarted(int request_id);
   void OnAudioStarted(int request_id);
   void OnSoundStarted(int request_id);
   void OnSoundEnded(int request_id);
   void OnAudioEnded(int request_id);
   void OnErrorOccurred(int request_id, const SpeechRecognitionError& error);
   void OnRecognitionEnded(int request_id);
   void OnResultsRetrieved(int request_id,
                           const SpeechRecognitionResults& result);
+  void OnAudioTrackReady(int session_id, const media::AudioParameters& params,
+                         base::SharedMemoryHandle handle, uint32 length);
+
+  // for receiving audio data via audio track

[henrika (OOO until Aug 14), 2014/08/25 14:46:00]

nit, capital 'F' end with period '.' as all other comments.

+  void OnAudioData(int request_id);
+  void OnAudioError(int request_id);
+  void OnAudioChunkProcessed(int request_id);
 
   int GetOrCreateIDForHandle(const blink::WebSpeechRecognitionHandle& handle);
   bool HandleExists(const blink::WebSpeechRecognitionHandle& handle);
   const blink::WebSpeechRecognitionHandle& GetHandleFromID(int handle_id);
 
   // The WebKit client class that we use to send events back to the JS world.
   blink::WebSpeechRecognizerClient* recognizer_client_;
 
+  // Media stream audio track that the speech recognition connects to.
+  // Accessed on the render thread.
+  blink::WebMediaStreamTrack audio_track_;
+
+  bool audio_track_set_;

[henrika (OOO until Aug 14), 2014/08/25 14:46:00]

Comment.

...and, capitals for all comments below ;-)

+
+  // Used by policy on which audio sources are allowed

[henrika (OOO until Aug 14), 2014/08/25 14:46:00]

Rather unclear comment to me. What is meant by "used by policy"?

+  bool is_allowed_audio_track_;
+
+  // audio sink used to provide audio from the track
+  scoped_ptr<SpeechRecognitionAudioSourceProvider> audio_source_provider_;
+
+  // for sending signal back to browser
+  scoped_refptr<base::MessageLoopProxy> render_loop_;
+
   typedef std::map<int, blink::WebSpeechRecognitionHandle> HandleMap;
   HandleMap handle_map_;
   int next_id_;
 
   DISALLOW_COPY_AND_ASSIGN(SpeechRecognitionDispatcher);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_SPEECH_RECOGNITION_DISPATCHER_H_