1 /* 2 * Copyright (C) 2010 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of 14 * its contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #ifndef AudioDestination_h 30 #define AudioDestination_h 31 32 #include "platform/audio/AudioBus.h" 33 #include "platform/audio/AudioIOCallback.h" 34 #include "platform/audio/AudioSourceProvider.h" 35 #include "public/platform/WebAudioDevice.h" 36 #include "public/platform/WebVector.h" 37 #include "wtf/Noncopyable.h" 38 #include "wtf/text/WTFString.h" 39 40 namespace WebCore { 41 42 class AudioFIFO; 43 class AudioPullFIFO; 44 45 // An AudioDestination using Chromium's audio system 46 47 class PLATFORM_EXPORT AudioDestination : public blink::WebAudioDevice::RenderCallback, public AudioSourceProvider { 48 WTF_MAKE_NONCOPYABLE(AudioDestination); 49 public: 50 AudioDestination(AudioIOCallback&, const String& inputDeviceId, unsigned numberOfInputChannels, unsigned numberOfOutputChannels, float sampleRate); 51 virtual ~AudioDestination(); 52 53 // Pass in (numberOfInputChannels > 0) if live/local audio input is desired. 54 // Port-specific device identification information for live/local input streams can be passed in the inputDeviceId. 55 static PassOwnPtr<AudioDestination> create(AudioIOCallback&, const String& inputDeviceId, unsigned numberOfInputChannels, unsigned numberOfOutputChannels, float sampleRate); 56 57 virtual void start(); 58 virtual void stop(); isPlaying()59 bool isPlaying() { return m_isPlaying; } 60 sampleRate()61 float sampleRate() const { return m_sampleRate; } 62 63 // blink::WebAudioDevice::RenderCallback 64 virtual void render(const blink::WebVector<float*>& sourceData, const blink::WebVector<float*>& audioData, size_t numberOfFrames) OVERRIDE; 65 66 // WebCore::AudioSourceProvider 67 virtual void provideInput(AudioBus*, size_t framesToProcess) OVERRIDE; 68 69 static float hardwareSampleRate(); 70 71 // maxChannelCount() returns the total number of output channels of the audio hardware. 72 // A value of 0 indicates that the number of channels cannot be configured and 73 // that only stereo (2-channel) destinations can be created. 74 // The numberOfOutputChannels parameter of AudioDestination::create() is allowed to 75 // be a value: 1 <= numberOfOutputChannels <= maxChannelCount(), 76 // or if maxChannelCount() equals 0, then numberOfOutputChannels must be 2. 77 static unsigned long maxChannelCount(); 78 79 private: 80 AudioIOCallback& m_callback; 81 unsigned m_numberOfOutputChannels; 82 RefPtr<AudioBus> m_inputBus; 83 RefPtr<AudioBus> m_renderBus; 84 float m_sampleRate; 85 bool m_isPlaying; 86 OwnPtr<blink::WebAudioDevice> m_audioDevice; 87 size_t m_callbackBufferSize; 88 89 OwnPtr<AudioFIFO> m_inputFifo; 90 OwnPtr<AudioPullFIFO> m_fifo; 91 }; 92 93 } // namespace WebCore 94 95 #endif // AudioDestination_h 96