Index: content/renderer/media/speech_recognition_audio_sink.h |
diff --git a/content/renderer/media/speech_recognition_audio_sink.h b/content/renderer/media/speech_recognition_audio_sink.h |
new file mode 100644 |
index 0000000000000000000000000000000000000000..7ba3f0c74ac1a9f815327c11c3d1d0f84b7bc082 |
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+++ b/content/renderer/media/speech_recognition_audio_sink.h |
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+// Copyright 2014 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_MEDIA_SPEECH_RECOGNITION_AUDIO_SINK_H_ |
+#define CONTENT_RENDERER_MEDIA_SPEECH_RECOGNITION_AUDIO_SINK_H_ |
+ |
+#include "base/callback.h" |
+#include "base/memory/scoped_ptr.h" |
+#include "base/memory/shared_memory.h" |
+#include "base/sync_socket.h" |
+#include "base/threading/thread_checker.h" |
+#include "content/common/content_export.h" |
+#include "content/public/renderer/media_stream_audio_sink.h" |
+#include "content/renderer/media/media_stream_audio_source.h" |
+#include "media/audio/audio_parameters.h" |
+#include "media/base/audio_converter.h" |
+#include "third_party/WebKit/public/platform/WebMediaStreamTrack.h" |
+ |
+namespace media { |
+class AudioBus; |
+class AudioFifo; |
+} |
+ |
+namespace content { |
+ |
+// SpeechRecognitionAudioSink works as an audio sink to the |
+// WebRtcLocalAudioTrack. It stores the capture data into a FIFO. |
+// When the FIFO has enough data for resampling, it converts it, |
+// passes the buffer to the WebSpeechRecognizer via SharedMemory |
+// and notifies it via SyncSocket followed by incrementing the |buffer_index_|. |
+// WebSpeechRecognizer increments the shared buffer index to synchronize. |
+class CONTENT_EXPORT SpeechRecognitionAudioSink |
+ : NON_EXPORTED_BASE(public media::AudioConverter::InputCallback), |
+ NON_EXPORTED_BASE(public MediaStreamAudioSink) { |
+ public: |
+ |
+ typedef base::Callback<void()> OnStoppedCB; |
+ |
+ // TODO(burnik): Add comments about owenrship of params/members. |
no longer working on chromium
2014/09/29 09:28:57
please address this TODO here
burnik
2014/09/29 10:24:31
Done.
|
+ SpeechRecognitionAudioSink(const blink::WebMediaStreamTrack& track, |
+ const media::AudioParameters& params, |
no longer working on chromium
2014/09/29 09:28:57
indentation.
burnik
2014/09/29 10:24:31
Done.
|
+ const base::SharedMemoryHandle memory, |
+ scoped_ptr<base::SyncSocket> socket, |
+ OnStoppedCB on_error_cb); |
+ |
+ virtual ~SpeechRecognitionAudioSink(); |
+ |
+ // Returns whether the provided track is supported. |
+ static bool IsSupportedTrack(const blink::WebMediaStreamTrack& track); |
+ |
+ private: |
+ // content::MediaStreamAudioSink implementation. |
+ virtual void OnReadyStateChanged( |
+ blink::WebMediaStreamSource::ReadyState state) OVERRIDE; |
+ |
+ virtual void OnData(const int16* audio_data, int sample_rate, |
+ int number_of_channels, int number_of_frames) OVERRIDE; |
+ virtual void OnSetFormat(const media::AudioParameters& params) OVERRIDE; |
+ |
+ // media::AudioConverter::Inputcallback implementation. |
+ virtual double ProvideInput(media::AudioBus* audio_bus, |
+ base::TimeDelta buffer_delay) OVERRIDE; |
+ |
+ // Number of frames per buffer in FIFO. When the buffer is full we convert and |
+ // consume it on the |output_bus_|. Size of the buffer depends on the |
+ // resampler. Example: for 44.1 to 16.0 conversion, it should be 4100 frames. |
+ int fifo_buffer_size_; |
+ |
+ // Used to DCHECK that some methods are called on the main render thread. |
+ base::ThreadChecker main_render_thread_checker_; |
+ |
+ // Used to DCHECK that some methods are called on the capture audio thread. |
+ base::ThreadChecker capture_thread_checker_; |
+ |
+ // The audio track that this audio sink is connected to. |
+ const blink::WebMediaStreamTrack track_; |
+ |
+ // Shared memory used by audio buses on both browser and renderer processes. |
+ base::SharedMemory shared_memory_; |
+ |
+ // Socket for syncronization of audio bus reads/writes. |
+ // Created on the renderer client and passed here. Accessed on capture thread. |
+ scoped_ptr<base::SyncSocket> socket_; |
+ |
+ // Used as a resampler to deliver appropriate format to speech recognition. |
+ scoped_ptr<media::AudioConverter> audio_converter_; |
+ |
+ // FIFO is used for queueing audio frames before we resample. |
+ scoped_ptr<media::AudioFifo> fifo_; |
+ |
+ // Audio delivered from source. |
+ scoped_ptr<media::AudioBus> input_bus_; |
+ |
+ // Audio bus shared with the browser process via |shared_memory_|. |
+ scoped_ptr<media::AudioBus> output_bus_; |
+ |
+ // Params of the source audio. Can change when |OnSetFormat()| occurs. |
+ media::AudioParameters input_params_; |
+ |
+ // Params used by speech recognition. |
+ const media::AudioParameters output_params_; |
+ |
+ // Whether the track has been stopped. |
+ bool track_stopped_; |
+ |
+ // Local counter of audio buffers for synchronization. |
+ uint32 buffer_index_; |
+ |
+ // Peer's counter of audio buffers for synchronization. |
+ const uint32* peer_buffer_index_; |
+ |
+ // Callback for the renderer client. Called when the audio track was stopped. |
+ const OnStoppedCB on_stopped_cb_; |
+ |
+ DISALLOW_COPY_AND_ASSIGN(SpeechRecognitionAudioSink); |
+}; |
+ |
+} // namespace content |
+ |
+#endif // CONTENT_RENDERER_MEDIA_SPEECH_RECOGNITION_AUDIO_SINK_H_ |