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 <wtf/OwnPtr.h> 33 #include <wtf/PassOwnPtr.h> 34 35 namespace WebCore { 36 37 class AudioSourceProvider; 38 39 // Abstraction for an audio output to the audio hardware 40 // An AudioSourceProvider is called back periodically to provide the rendered audio stream. 41 42 class AudioDestination { 43 public: 44 static PassOwnPtr<AudioDestination> create(AudioSourceProvider&, double sampleRate); 45 ~AudioDestination()46 virtual ~AudioDestination() { } 47 48 virtual void start() = 0; 49 virtual void stop() = 0; 50 virtual bool isPlaying() = 0; 51 52 // Sample-rate conversion may happen in AudioDestination to the hardware sample-rate 53 virtual double sampleRate() const = 0; 54 static double hardwareSampleRate(); 55 }; 56 57 } // namespace WebCore 58 59 #endif // AudioDestination_h 60