1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/content/media/webaudio/blink/DynamicsCompressor.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,130 @@
1.4 +/*
1.5 + * Copyright (C) 2011 Google Inc. All rights reserved.
1.6 + *
1.7 + * Redistribution and use in source and binary forms, with or without
1.8 + * modification, are permitted provided that the following conditions
1.9 + * are met:
1.10 + *
1.11 + * 1. Redistributions of source code must retain the above copyright
1.12 + * notice, this list of conditions and the following disclaimer.
1.13 + * 2. Redistributions in binary form must reproduce the above copyright
1.14 + * notice, this list of conditions and the following disclaimer in the
1.15 + * documentation and/or other materials provided with the distribution.
1.16 + * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
1.17 + * its contributors may be used to endorse or promote products derived
1.18 + * from this software without specific prior written permission.
1.19 + *
1.20 + * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
1.21 + * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
1.22 + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
1.23 + * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
1.24 + * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
1.25 + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
1.26 + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
1.27 + * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1.28 + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
1.29 + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.30 + */
1.31 +
1.32 +#ifndef DynamicsCompressor_h
1.33 +#define DynamicsCompressor_h
1.34 +
1.35 +#include "DynamicsCompressorKernel.h"
1.36 +#include "ZeroPole.h"
1.37 +
1.38 +#include "nsTArray.h"
1.39 +#include "nsAutoPtr.h"
1.40 +#include "mozilla/MemoryReporting.h"
1.41 +
1.42 +namespace mozilla {
1.43 +struct AudioChunk;
1.44 +}
1.45 +
1.46 +namespace WebCore {
1.47 +
1.48 +using mozilla::AudioChunk;
1.49 +
1.50 +// DynamicsCompressor implements a flexible audio dynamics compression effect such as
1.51 +// is commonly used in musical production and game audio. It lowers the volume
1.52 +// of the loudest parts of the signal and raises the volume of the softest parts,
1.53 +// making the sound richer, fuller, and more controlled.
1.54 +
1.55 +class DynamicsCompressor {
1.56 +public:
1.57 + enum {
1.58 + ParamThreshold,
1.59 + ParamKnee,
1.60 + ParamRatio,
1.61 + ParamAttack,
1.62 + ParamRelease,
1.63 + ParamPreDelay,
1.64 + ParamReleaseZone1,
1.65 + ParamReleaseZone2,
1.66 + ParamReleaseZone3,
1.67 + ParamReleaseZone4,
1.68 + ParamPostGain,
1.69 + ParamFilterStageGain,
1.70 + ParamFilterStageRatio,
1.71 + ParamFilterAnchor,
1.72 + ParamEffectBlend,
1.73 + ParamReduction,
1.74 + ParamLast
1.75 + };
1.76 +
1.77 + DynamicsCompressor(float sampleRate, unsigned numberOfChannels);
1.78 +
1.79 + void process(const AudioChunk* sourceChunk, AudioChunk* destinationChunk, unsigned framesToProcess);
1.80 + void reset();
1.81 + void setNumberOfChannels(unsigned);
1.82 + unsigned numberOfChannels() const { return m_numberOfChannels; }
1.83 +
1.84 + void setParameterValue(unsigned parameterID, float value);
1.85 + float parameterValue(unsigned parameterID);
1.86 +
1.87 + float sampleRate() const { return m_sampleRate; }
1.88 + float nyquist() const { return m_sampleRate / 2; }
1.89 +
1.90 + double tailTime() const { return 0; }
1.91 + double latencyTime() const { return m_compressor.latencyFrames() / static_cast<double>(sampleRate()); }
1.92 +
1.93 + size_t sizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
1.94 +
1.95 +protected:
1.96 + unsigned m_numberOfChannels;
1.97 +
1.98 + // m_parameters holds the tweakable compressor parameters.
1.99 + float m_parameters[ParamLast];
1.100 + void initializeParameters();
1.101 +
1.102 + float m_sampleRate;
1.103 +
1.104 + // Emphasis filter controls.
1.105 + float m_lastFilterStageRatio;
1.106 + float m_lastAnchor;
1.107 + float m_lastFilterStageGain;
1.108 +
1.109 + typedef struct {
1.110 + ZeroPole filters[4];
1.111 + size_t sizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const
1.112 + {
1.113 + return aMallocSizeOf(this);
1.114 + }
1.115 + } ZeroPoleFilterPack4;
1.116 +
1.117 + // Per-channel emphasis filters.
1.118 + nsTArray<nsAutoPtr<ZeroPoleFilterPack4> > m_preFilterPacks;
1.119 + nsTArray<nsAutoPtr<ZeroPoleFilterPack4> > m_postFilterPacks;
1.120 +
1.121 + nsAutoArrayPtr<const float*> m_sourceChannels;
1.122 + nsAutoArrayPtr<float*> m_destinationChannels;
1.123 +
1.124 + void setEmphasisStageParameters(unsigned stageIndex, float gain, float normalizedFrequency /* 0 -> 1 */);
1.125 + void setEmphasisParameters(float gain, float anchorFreq, float filterStageRatio);
1.126 +
1.127 + // The core compressor.
1.128 + DynamicsCompressorKernel m_compressor;
1.129 +};
1.130 +
1.131 +} // namespace WebCore
1.132 +
1.133 +#endif // DynamicsCompressor_h
