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 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 16 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY 17 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 18 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 22 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23 */ 24 25 #ifndef AudioDelayDSPKernel_h 26 #define AudioDelayDSPKernel_h 27 28 #include "platform/audio/AudioArray.h" 29 #include "platform/audio/AudioDSPKernel.h" 30 31 namespace WebCore { 32 33 class PLATFORM_EXPORT AudioDelayDSPKernel : public AudioDSPKernel { 34 public: 35 AudioDelayDSPKernel(double maxDelayTime, float sampleRate); 36 37 virtual void process(const float* source, float* destination, size_t framesToProcess) OVERRIDE; 38 virtual void reset() OVERRIDE; 39 maxDelayTime()40 double maxDelayTime() const { return m_maxDelayTime; } 41 setDelayFrames(double numberOfFrames)42 void setDelayFrames(double numberOfFrames) { m_desiredDelayFrames = numberOfFrames; } 43 44 virtual double tailTime() const OVERRIDE; 45 virtual double latencyTime() const OVERRIDE; 46 47 protected: 48 AudioDelayDSPKernel(AudioDSPKernelProcessor*, size_t processingSizeInFrames); 49 50 virtual bool hasSampleAccurateValues(); 51 virtual void calculateSampleAccurateValues(float* delayTimes, size_t framesToProcess); 52 virtual double delayTime(float sampleRate); 53 54 AudioFloatArray m_buffer; 55 double m_maxDelayTime; 56 int m_writeIndex; 57 double m_currentDelayTime; 58 double m_smoothingRate; 59 bool m_firstTime; 60 double m_desiredDelayFrames; 61 62 AudioFloatArray m_delayTimes; 63 64 size_t bufferLengthForDelay(double delayTime, double sampleRate) const; 65 }; 66 67 } // namespace WebCore 68 69 #endif // AudioDelayDSPKernel_h 70