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 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#include "config.h" 30 31#if ENABLE(WEB_AUDIO) 32 33#include "HRTFDatabase.h" 34 35#include "HRTFElevation.h" 36 37namespace WebCore { 38 39const int HRTFDatabase::MinElevation = -45; 40const int HRTFDatabase::MaxElevation = 90; 41const unsigned HRTFDatabase::RawElevationAngleSpacing = 15; 42const unsigned HRTFDatabase::NumberOfRawElevations = 10; // -45 -> +90 (each 15 degrees) 43const unsigned HRTFDatabase::InterpolationFactor = 1; 44const unsigned HRTFDatabase::NumberOfTotalElevations = NumberOfRawElevations * InterpolationFactor; 45 46HRTFDatabase::HRTFDatabase(float sampleRate) 47 : m_elevations(NumberOfTotalElevations) 48 , m_sampleRate(sampleRate) 49{ 50 unsigned elevationIndex = 0; 51 for (int elevation = MinElevation; elevation <= MaxElevation; elevation += RawElevationAngleSpacing) { 52 std::unique_ptr<HRTFElevation> hrtfElevation = HRTFElevation::createForSubject("Composite", elevation, sampleRate); 53 ASSERT(hrtfElevation.get()); 54 if (!hrtfElevation.get()) 55 return; 56 57 m_elevations[elevationIndex] = WTF::move(hrtfElevation); 58 elevationIndex += InterpolationFactor; 59 } 60 61 // Now, go back and interpolate elevations. 62 if (InterpolationFactor > 1) { 63 for (unsigned i = 0; i < NumberOfTotalElevations; i += InterpolationFactor) { 64 unsigned j = (i + InterpolationFactor); 65 if (j >= NumberOfTotalElevations) 66 j = i; // for last elevation interpolate with itself 67 68 // Create the interpolated convolution kernels and delays. 69 for (unsigned jj = 1; jj < InterpolationFactor; ++jj) { 70 float x = static_cast<float>(jj) / static_cast<float>(InterpolationFactor); 71 m_elevations[i + jj] = HRTFElevation::createByInterpolatingSlices(m_elevations[i].get(), m_elevations[j].get(), x, sampleRate); 72 ASSERT(m_elevations[i + jj].get()); 73 } 74 } 75 } 76} 77 78void HRTFDatabase::getKernelsFromAzimuthElevation(double azimuthBlend, unsigned azimuthIndex, double elevationAngle, HRTFKernel* &kernelL, HRTFKernel* &kernelR, 79 double& frameDelayL, double& frameDelayR) 80{ 81 unsigned elevationIndex = indexFromElevationAngle(elevationAngle); 82 ASSERT_WITH_SECURITY_IMPLICATION(elevationIndex < m_elevations.size() && m_elevations.size() > 0); 83 84 if (!m_elevations.size()) { 85 kernelL = 0; 86 kernelR = 0; 87 return; 88 } 89 90 if (elevationIndex > m_elevations.size() - 1) 91 elevationIndex = m_elevations.size() - 1; 92 93 HRTFElevation* hrtfElevation = m_elevations[elevationIndex].get(); 94 ASSERT(hrtfElevation); 95 if (!hrtfElevation) { 96 kernelL = 0; 97 kernelR = 0; 98 return; 99 } 100 101 hrtfElevation->getKernelsFromAzimuth(azimuthBlend, azimuthIndex, kernelL, kernelR, frameDelayL, frameDelayR); 102} 103 104unsigned HRTFDatabase::indexFromElevationAngle(double elevationAngle) 105{ 106 // Clamp to allowed range. 107 elevationAngle = std::max(static_cast<double>(MinElevation), elevationAngle); 108 elevationAngle = std::min(static_cast<double>(MaxElevation), elevationAngle); 109 110 unsigned elevationIndex = static_cast<int>(InterpolationFactor * (elevationAngle - MinElevation) / RawElevationAngleSpacing); 111 return elevationIndex; 112} 113 114} // namespace WebCore 115 116#endif // ENABLE(WEB_AUDIO) 117