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 #include "config.h" 26 27 #if ENABLE(WEB_AUDIO) 28 29 #include "modules/webaudio/DelayDSPKernel.h" 30 31 #include "platform/audio/AudioUtilities.h" 32 #include "wtf/MathExtras.h" 33 #include <algorithm> 34 35 using namespace std; 36 37 namespace WebCore { 38 39 const float SmoothingTimeConstant = 0.020f; // 20ms 40 41 DelayDSPKernel::DelayDSPKernel(DelayProcessor* processor) 42 : AudioDelayDSPKernel(processor, AudioNode::ProcessingSizeInFrames) 43 { 44 ASSERT(processor && processor->sampleRate() > 0); 45 if (!(processor && processor->sampleRate() > 0)) 46 return; 47 48 m_maxDelayTime = processor->maxDelayTime(); 49 ASSERT(m_maxDelayTime >= 0 && !std::isnan(m_maxDelayTime)); 50 if (m_maxDelayTime < 0 || std::isnan(m_maxDelayTime)) 51 return; 52 53 m_buffer.allocate(bufferLengthForDelay(m_maxDelayTime, processor->sampleRate())); 54 m_buffer.zero(); 55 56 m_smoothingRate = AudioUtilities::discreteTimeConstantForSampleRate(SmoothingTimeConstant, processor->sampleRate()); 57 } 58 59 bool DelayDSPKernel::hasSampleAccurateValues() 60 { 61 return delayProcessor()->delayTime()->hasSampleAccurateValues(); 62 } 63 64 void DelayDSPKernel::calculateSampleAccurateValues(float* delayTimes, size_t framesToProcess) 65 { 66 delayProcessor()->delayTime()->calculateSampleAccurateValues(delayTimes, framesToProcess); 67 } 68 69 double DelayDSPKernel::delayTime(float) 70 { 71 return delayProcessor()->delayTime()->finalValue(); 72 } 73 74 } // namespace WebCore 75 76 #endif // ENABLE(WEB_AUDIO) 77
