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