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 Computer, 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 #ifndef HRTFElevation_h 30 #define HRTFElevation_h 31 32 #include "core/platform/audio/HRTFKernel.h" 33 #include "wtf/Noncopyable.h" 34 #include "wtf/OwnPtr.h" 35 #include "wtf/PassOwnPtr.h" 36 #include "wtf/PassRefPtr.h" 37 #include "wtf/RefCounted.h" 38 #include "wtf/RefPtr.h" 39 #include "wtf/text/CString.h" 40 #include "wtf/text/WTFString.h" 41 42 namespace WebCore { 43 44 // HRTFElevation contains all of the HRTFKernels (one left ear and one right ear per azimuth angle) for a particular elevation. 45 46 class HRTFElevation { 47 WTF_MAKE_NONCOPYABLE(HRTFElevation); 48 public: 49 // Loads and returns an HRTFElevation with the given HRTF database subject name and elevation from browser (or WebKit.framework) resources. 50 // Normally, there will only be a single HRTF database set, but this API supports the possibility of multiple ones with different names. 51 // Interpolated azimuths will be generated based on InterpolationFactor. 52 // Valid values for elevation are -45 -> +90 in 15 degree increments. 53 static PassOwnPtr<HRTFElevation> createForSubject(const String& subjectName, int elevation, float sampleRate); 54 55 // Given two HRTFElevations, and an interpolation factor x: 0 -> 1, returns an interpolated HRTFElevation. 56 static PassOwnPtr<HRTFElevation> createByInterpolatingSlices(HRTFElevation* hrtfElevation1, HRTFElevation* hrtfElevation2, float x, float sampleRate); 57 58 // Returns the list of left or right ear HRTFKernels for all the azimuths going from 0 to 360 degrees. 59 HRTFKernelList* kernelListL() { return m_kernelListL.get(); } 60 HRTFKernelList* kernelListR() { return m_kernelListR.get(); } 61 62 double elevationAngle() const { return m_elevationAngle; } 63 unsigned numberOfAzimuths() const { return NumberOfTotalAzimuths; } 64 float sampleRate() const { return m_sampleRate; } 65 66 // Returns the left and right kernels for the given azimuth index. 67 // The interpolated delays based on azimuthBlend: 0 -> 1 are returned in frameDelayL and frameDelayR. 68 void getKernelsFromAzimuth(double azimuthBlend, unsigned azimuthIndex, HRTFKernel* &kernelL, HRTFKernel* &kernelR, double& frameDelayL, double& frameDelayR); 69 70 // Spacing, in degrees, between every azimuth loaded from resource. 71 static const unsigned AzimuthSpacing; 72 73 // Number of azimuths loaded from resource. 74 static const unsigned NumberOfRawAzimuths; 75 76 // Interpolates by this factor to get the total number of azimuths from every azimuth loaded from resource. 77 static const unsigned InterpolationFactor; 78 79 // Total number of azimuths after interpolation. 80 static const unsigned NumberOfTotalAzimuths; 81 82 // Given a specific azimuth and elevation angle, returns the left and right HRTFKernel. 83 // Valid values for azimuth are 0 -> 345 in 15 degree increments. 84 // Valid values for elevation are -45 -> +90 in 15 degree increments. 85 // Returns true on success. 86 static bool calculateKernelsForAzimuthElevation(int azimuth, int elevation, float sampleRate, const String& subjectName, 87 RefPtr<HRTFKernel>& kernelL, RefPtr<HRTFKernel>& kernelR); 88 89 // Given a specific azimuth and elevation angle, returns the left and right HRTFKernel in kernelL and kernelR. 90 // This method averages the measured response using symmetry of azimuth (for example by averaging the -30.0 and +30.0 azimuth responses). 91 // Returns true on success. 92 static bool calculateSymmetricKernelsForAzimuthElevation(int azimuth, int elevation, float sampleRate, const String& subjectName, 93 RefPtr<HRTFKernel>& kernelL, RefPtr<HRTFKernel>& kernelR); 94 95 private: 96 HRTFElevation(PassOwnPtr<HRTFKernelList> kernelListL, PassOwnPtr<HRTFKernelList> kernelListR, int elevation, float sampleRate) 97 : m_kernelListL(kernelListL) 98 , m_kernelListR(kernelListR) 99 , m_elevationAngle(elevation) 100 , m_sampleRate(sampleRate) 101 { 102 } 103 104 OwnPtr<HRTFKernelList> m_kernelListL; 105 OwnPtr<HRTFKernelList> m_kernelListR; 106 double m_elevationAngle; 107 float m_sampleRate; 108 }; 109 110 } // namespace WebCore 111 112 #endif // HRTFElevation_h 113
