content/media/webaudio/blink/PeriodicWave.h@97036ab72558 (annotated)
content/media/webaudio/blink/PeriodicWave.h
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | /* |
| michael@0 | 2 | * Copyright (C) 2012 Google Inc. All rights reserved. |
| michael@0 | 3 | * |
| michael@0 | 4 | * Redistribution and use in source and binary forms, with or without |
| michael@0 | 5 | * modification, are permitted provided that the following conditions |
| michael@0 | 6 | * are met: |
| michael@0 | 7 | * |
| michael@0 | 8 | * 1. Redistributions of source code must retain the above copyright |
| michael@0 | 9 | * notice, this list of conditions and the following disclaimer. |
| michael@0 | 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| michael@0 | 11 | * notice, this list of conditions and the following disclaimer in the |
| michael@0 | 12 | * documentation and/or other materials provided with the distribution. |
| michael@0 | 13 | * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of |
| michael@0 | 14 | * its contributors may be used to endorse or promote products derived |
| michael@0 | 15 | * from this software without specific prior written permission. |
| michael@0 | 16 | * |
| michael@0 | 17 | * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY |
| michael@0 | 18 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| michael@0 | 19 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| michael@0 | 20 | * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY |
| michael@0 | 21 | * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| michael@0 | 22 | * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| michael@0 | 23 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| michael@0 | 24 | * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| michael@0 | 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| michael@0 | 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| michael@0 | 27 | */ |
| michael@0 | 28 | |
| michael@0 | 29 | #ifndef PeriodicWave_h |
| michael@0 | 30 | #define PeriodicWave_h |
| michael@0 | 31 | |
| michael@0 | 32 | #include "mozilla/dom/OscillatorNodeBinding.h" |
| michael@0 | 33 | #include <nsAutoPtr.h> |
| michael@0 | 34 | #include <nsTArray.h> |
| michael@0 | 35 | #include "mozilla/MemoryReporting.h" |
| michael@0 | 36 | |
| michael@0 | 37 | namespace WebCore { |
| michael@0 | 38 | |
| michael@0 | 39 | typedef nsTArray<float> AudioFloatArray; |
| michael@0 | 40 | |
| michael@0 | 41 | class PeriodicWave { |
| michael@0 | 42 | public: |
| michael@0 | 43 | static PeriodicWave* createSine(float sampleRate); |
| michael@0 | 44 | static PeriodicWave* createSquare(float sampleRate); |
| michael@0 | 45 | static PeriodicWave* createSawtooth(float sampleRate); |
| michael@0 | 46 | static PeriodicWave* createTriangle(float sampleRate); |
| michael@0 | 47 | |
| michael@0 | 48 | // Creates an arbitrary periodic wave given the frequency components |
| michael@0 | 49 | // (Fourier coefficients). |
| michael@0 | 50 | static PeriodicWave* create(float sampleRate, |
| michael@0 | 51 | const float* real, |
| michael@0 | 52 | const float* imag, |
| michael@0 | 53 | size_t numberOfComponents); |
| michael@0 | 54 | |
| michael@0 | 55 | // Returns pointers to the lower and higher wave data for the pitch range |
| michael@0 | 56 | // containing the given fundamental frequency. These two tables are in |
| michael@0 | 57 | // adjacent "pitch" ranges where the higher table will have the maximum |
| michael@0 | 58 | // number of partials which won't alias when played back at this |
| michael@0 | 59 | // fundamental frequency. The lower wave is the next range containing fewer |
| michael@0 | 60 | // partials than the higher wave. Interpolation between these two tables |
| michael@0 | 61 | // can be made according to tableInterpolationFactor. Where values |
| michael@0 | 62 | // from 0 -> 1 interpolate between lower -> higher. |
| michael@0 | 63 | void waveDataForFundamentalFrequency(float, float* &lowerWaveData, float* &higherWaveData, float& tableInterpolationFactor); |
| michael@0 | 64 | |
| michael@0 | 65 | // Returns the scalar multiplier to the oscillator frequency to calculate |
| michael@0 | 66 | // wave buffer phase increment. |
| michael@0 | 67 | float rateScale() const { return m_rateScale; } |
| michael@0 | 68 | |
| michael@0 | 69 | unsigned periodicWaveSize() const { return m_periodicWaveSize; } |
| michael@0 | 70 | float sampleRate() const { return m_sampleRate; } |
| michael@0 | 71 | |
| michael@0 | 72 | size_t sizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const; |
| michael@0 | 73 | |
| michael@0 | 74 | private: |
| michael@0 | 75 | explicit PeriodicWave(float sampleRate); |
| michael@0 | 76 | |
| michael@0 | 77 | void generateBasicWaveform(mozilla::dom::OscillatorType); |
| michael@0 | 78 | |
| michael@0 | 79 | float m_sampleRate; |
| michael@0 | 80 | unsigned m_periodicWaveSize; |
| michael@0 | 81 | unsigned m_numberOfRanges; |
| michael@0 | 82 | float m_centsPerRange; |
| michael@0 | 83 | |
| michael@0 | 84 | // The lowest frequency (in Hertz) where playback will include all of the |
| michael@0 | 85 | // partials. Playing back lower than this frequency will gradually lose |
| michael@0 | 86 | // more high-frequency information. |
| michael@0 | 87 | // This frequency is quite low (~10Hz @ // 44.1KHz) |
| michael@0 | 88 | float m_lowestFundamentalFrequency; |
| michael@0 | 89 | |
| michael@0 | 90 | float m_rateScale; |
| michael@0 | 91 | |
| michael@0 | 92 | unsigned numberOfRanges() const { return m_numberOfRanges; } |
| michael@0 | 93 | |
| michael@0 | 94 | // Maximum possible number of partials (before culling). |
| michael@0 | 95 | unsigned maxNumberOfPartials() const; |
| michael@0 | 96 | |
| michael@0 | 97 | unsigned numberOfPartialsForRange(unsigned rangeIndex) const; |
| michael@0 | 98 | |
| michael@0 | 99 | // Creates tables based on numberOfComponents Fourier coefficients. |
| michael@0 | 100 | void createBandLimitedTables(const float* real, const float* imag, unsigned numberOfComponents); |
| michael@0 | 101 | nsTArray<nsAutoPtr<AudioFloatArray> > m_bandLimitedTables; |
| michael@0 | 102 | }; |
| michael@0 | 103 | |
| michael@0 | 104 | } // namespace WebCore |
| michael@0 | 105 | |
| michael@0 | 106 | #endif // PeriodicWave_h |
