OLD | NEW |
| (Empty) |
1 // Copyright (c) 2012 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 CONTENT_RENDERER_MEDIA_WEBAUDIO_MEDIA_STREAM_SOURCE_H_ | |
6 #define CONTENT_RENDERER_MEDIA_WEBAUDIO_MEDIA_STREAM_SOURCE_H_ | |
7 | |
8 #include <memory> | |
9 | |
10 #include "base/time/time.h" | |
11 #include "content/renderer/media/media_stream_audio_source.h" | |
12 #include "media/base/audio_bus.h" | |
13 #include "media/base/audio_push_fifo.h" | |
14 #include "third_party/WebKit/public/platform/WebAudioDestinationConsumer.h" | |
15 #include "third_party/WebKit/public/platform/WebMediaStreamSource.h" | |
16 #include "third_party/WebKit/public/platform/WebVector.h" | |
17 | |
18 namespace content { | |
19 | |
20 // Implements the WebAudioDestinationConsumer interface to provide a source of | |
21 // audio data (i.e., the output from a graph of WebAudio nodes) to one or more | |
22 // MediaStreamAudioTracks. Audio data is transported directly to the tracks in | |
23 // 10 ms chunks. | |
24 class WebAudioMediaStreamSource final | |
25 : NON_EXPORTED_BASE(public MediaStreamAudioSource), | |
26 public blink::WebAudioDestinationConsumer { | |
27 public: | |
28 explicit WebAudioMediaStreamSource(blink::WebMediaStreamSource* blink_source); | |
29 | |
30 ~WebAudioMediaStreamSource() override; | |
31 | |
32 private: | |
33 // WebAudioDestinationConsumer implementation. | |
34 // | |
35 // Note: Blink ensures setFormat() and consumeAudio() are not called | |
36 // concurrently across threads, but these methods could be called on any | |
37 // thread. | |
38 void setFormat(size_t number_of_channels, float sample_rate) override; | |
39 void consumeAudio(const blink::WebVector<const float*>& audio_data, | |
40 size_t number_of_frames) override; | |
41 | |
42 // Called by AudioPushFifo zero or more times during the call to | |
43 // consumeAudio(). Delivers audio data with the required buffer size to the | |
44 // tracks. | |
45 void DeliverRebufferedAudio(const media::AudioBus& audio_bus, | |
46 int frame_delay); | |
47 | |
48 // MediaStreamAudioSource implementation. | |
49 bool EnsureSourceIsStarted() final; | |
50 void EnsureSourceIsStopped() final; | |
51 | |
52 // In debug builds, check that all methods that could cause object graph | |
53 // or data flow changes are being called on the main thread. | |
54 base::ThreadChecker thread_checker_; | |
55 | |
56 // True while this WebAudioMediaStreamSource is registered with | |
57 // |blink_source_| and is consuming audio. | |
58 bool is_registered_consumer_; | |
59 | |
60 // A wrapper used for providing audio to |fifo_|. | |
61 std::unique_ptr<media::AudioBus> wrapper_bus_; | |
62 | |
63 // Takes in the audio data passed to consumeAudio() and re-buffers it into 10 | |
64 // ms chunks for the tracks. This ensures each chunk of audio delivered to | |
65 // the tracks has the required buffer size, regardless of the amount of audio | |
66 // provided via each consumeAudio() call. | |
67 media::AudioPushFifo fifo_; | |
68 | |
69 // Used to pass the reference timestamp between DeliverDecodedAudio() and | |
70 // DeliverRebufferedAudio(). | |
71 base::TimeTicks current_reference_time_; | |
72 | |
73 // This object registers with a blink::WebMediaStreamSource. We keep track of | |
74 // that in order to be able to deregister before stopping this source. | |
75 blink::WebMediaStreamSource blink_source_; | |
76 | |
77 DISALLOW_COPY_AND_ASSIGN(WebAudioMediaStreamSource); | |
78 }; | |
79 | |
80 } // namespace content | |
81 | |
82 #endif // CONTENT_RENDERER_MEDIA_WEBAUDIO_MEDIA_STREAM_SOURCE_H_ | |
OLD | NEW |