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