| /* |
| * Copyright (C) 2010 Google Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of |
| * its contributors may be used to endorse or promote products derived |
| * from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY |
| * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| |
| #if ENABLE(WEB_AUDIO) |
| |
| #include "platform/audio/HRTFDatabase.h" |
| |
| #include "platform/audio/HRTFElevation.h" |
| |
| using namespace std; |
| |
| namespace WebCore { |
| |
| const int HRTFDatabase::MinElevation = -45; |
| const int HRTFDatabase::MaxElevation = 90; |
| const unsigned HRTFDatabase::RawElevationAngleSpacing = 15; |
| const unsigned HRTFDatabase::NumberOfRawElevations = 10; // -45 -> +90 (each 15 degrees) |
| const unsigned HRTFDatabase::InterpolationFactor = 1; |
| const unsigned HRTFDatabase::NumberOfTotalElevations = NumberOfRawElevations * InterpolationFactor; |
| |
| PassOwnPtr<HRTFDatabase> HRTFDatabase::create(float sampleRate) |
| { |
| OwnPtr<HRTFDatabase> hrtfDatabase = adoptPtr(new HRTFDatabase(sampleRate)); |
| return hrtfDatabase.release(); |
| } |
| |
| HRTFDatabase::HRTFDatabase(float sampleRate) |
| : m_elevations(NumberOfTotalElevations) |
| , m_sampleRate(sampleRate) |
| { |
| unsigned elevationIndex = 0; |
| for (int elevation = MinElevation; elevation <= MaxElevation; elevation += RawElevationAngleSpacing) { |
| OwnPtr<HRTFElevation> hrtfElevation = HRTFElevation::createForSubject("Composite", elevation, sampleRate); |
| ASSERT(hrtfElevation.get()); |
| if (!hrtfElevation.get()) |
| return; |
| |
| m_elevations[elevationIndex] = hrtfElevation.release(); |
| elevationIndex += InterpolationFactor; |
| } |
| |
| // Now, go back and interpolate elevations. |
| if (InterpolationFactor > 1) { |
| for (unsigned i = 0; i < NumberOfTotalElevations; i += InterpolationFactor) { |
| unsigned j = (i + InterpolationFactor); |
| if (j >= NumberOfTotalElevations) |
| j = i; // for last elevation interpolate with itself |
| |
| // Create the interpolated convolution kernels and delays. |
| for (unsigned jj = 1; jj < InterpolationFactor; ++jj) { |
| float x = static_cast<float>(jj) / static_cast<float>(InterpolationFactor); |
| m_elevations[i + jj] = HRTFElevation::createByInterpolatingSlices(m_elevations[i].get(), m_elevations[j].get(), x, sampleRate); |
| ASSERT(m_elevations[i + jj].get()); |
| } |
| } |
| } |
| } |
| |
| void HRTFDatabase::getKernelsFromAzimuthElevation(double azimuthBlend, unsigned azimuthIndex, double elevationAngle, HRTFKernel* &kernelL, HRTFKernel* &kernelR, |
| double& frameDelayL, double& frameDelayR) |
| { |
| unsigned elevationIndex = indexFromElevationAngle(elevationAngle); |
| ASSERT_WITH_SECURITY_IMPLICATION(elevationIndex < m_elevations.size() && m_elevations.size() > 0); |
| |
| if (!m_elevations.size()) { |
| kernelL = 0; |
| kernelR = 0; |
| return; |
| } |
| |
| if (elevationIndex > m_elevations.size() - 1) |
| elevationIndex = m_elevations.size() - 1; |
| |
| HRTFElevation* hrtfElevation = m_elevations[elevationIndex].get(); |
| ASSERT(hrtfElevation); |
| if (!hrtfElevation) { |
| kernelL = 0; |
| kernelR = 0; |
| return; |
| } |
| |
| hrtfElevation->getKernelsFromAzimuth(azimuthBlend, azimuthIndex, kernelL, kernelR, frameDelayL, frameDelayR); |
| } |
| |
| unsigned HRTFDatabase::indexFromElevationAngle(double elevationAngle) |
| { |
| // Clamp to allowed range. |
| elevationAngle = max(static_cast<double>(MinElevation), elevationAngle); |
| elevationAngle = min(static_cast<double>(MaxElevation), elevationAngle); |
| |
| unsigned elevationIndex = static_cast<int>(InterpolationFactor * (elevationAngle - MinElevation) / RawElevationAngleSpacing); |
| return elevationIndex; |
| } |
| |
| } // namespace WebCore |
| |
| #endif // ENABLE(WEB_AUDIO) |