1 /* 2 * Copyright (C) 2012 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 PeriodicWave_h 30 #define PeriodicWave_h 31 32 #include "mozilla/dom/OscillatorNodeBinding.h" 33 #include "mozilla/UniquePtr.h" 34 #include <nsTArray.h> 35 #include "AlignedTArray.h" 36 #include "mozilla/MemoryReporting.h" 37 38 namespace WebCore { 39 40 typedef AlignedTArray<float> AlignedAudioFloatArray; 41 typedef nsTArray<float> AudioFloatArray; 42 43 using mozilla::UniquePtr; 44 45 class PeriodicWave { 46 public: 47 NS_INLINE_DECL_THREADSAFE_REFCOUNTING(WebCore::PeriodicWave); 48 49 static already_AddRefed<PeriodicWave> createSine(float sampleRate); 50 static already_AddRefed<PeriodicWave> createSquare(float sampleRate); 51 static already_AddRefed<PeriodicWave> createSawtooth(float sampleRate); 52 static already_AddRefed<PeriodicWave> createTriangle(float sampleRate); 53 54 // Creates an arbitrary periodic wave given the frequency components 55 // (Fourier coefficients). 56 static already_AddRefed<PeriodicWave> create(float sampleRate, 57 const float* real, 58 const float* imag, 59 size_t numberOfComponents, 60 bool disableNormalization); 61 62 // Returns pointers to the lower and higher wave data for the pitch range 63 // containing the given fundamental frequency. These two tables are in 64 // adjacent "pitch" ranges where the higher table will have the maximum 65 // number of partials which won't alias when played back at this 66 // fundamental frequency. The lower wave is the next range containing fewer 67 // partials than the higher wave. Interpolation between these two tables 68 // can be made according to tableInterpolationFactor. Where values 69 // from 0 -> 1 interpolate between lower -> higher. 70 void waveDataForFundamentalFrequency(float, float*& lowerWaveData, 71 float*& higherWaveData, 72 float& tableInterpolationFactor); 73 74 // Returns the scalar multiplier to the oscillator frequency to calculate 75 // wave buffer phase increment. rateScale()76 float rateScale() const { return m_rateScale; } 77 periodicWaveSize()78 unsigned periodicWaveSize() const { return m_periodicWaveSize; } sampleRate()79 float sampleRate() const { return m_sampleRate; } 80 81 size_t sizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const; 82 83 private: 84 explicit PeriodicWave(float sampleRate, size_t numberOfComponents, 85 bool disableNormalization); 86 ~PeriodicWave() = default; 87 88 void generateBasicWaveform(mozilla::dom::OscillatorType); 89 90 float m_sampleRate; 91 unsigned m_periodicWaveSize; 92 unsigned m_numberOfRanges; 93 float m_centsPerRange; 94 unsigned m_numberOfComponents; 95 UniquePtr<AudioFloatArray> m_realComponents; 96 UniquePtr<AudioFloatArray> m_imagComponents; 97 98 // The lowest frequency (in Hertz) where playback will include all of the 99 // partials. Playing back lower than this frequency will gradually lose 100 // more high-frequency information. 101 // This frequency is quite low (~10Hz @ // 44.1KHz) 102 float m_lowestFundamentalFrequency; 103 104 float m_rateScale; 105 numberOfRanges()106 unsigned numberOfRanges() const { return m_numberOfRanges; } 107 108 // Maximum possible number of partials (before culling). 109 unsigned maxNumberOfPartials() const; 110 111 unsigned numberOfPartialsForRange(unsigned rangeIndex) const; 112 113 // Creates table for specified index based on fundamental frequency. 114 void createBandLimitedTables(float fundamentalFrequency, unsigned rangeIndex); 115 unsigned m_maxPartialsInBandLimitedTable; 116 float m_normalizationScale; 117 bool m_disableNormalization; 118 nsTArray<UniquePtr<AlignedAudioFloatArray> > m_bandLimitedTables; 119 }; 120 121 } // namespace WebCore 122 123 #endif // PeriodicWave_h 124