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29 #ifndef DynamicsCompressorKernel_h
30 #define DynamicsCompressorKernel_h
32 #include "AudioArray.h"
34 #include <wtf/OwnPtr.h>
35 #include <wtf/PassOwnPtr.h>
39 class DynamicsCompressorKernel {
41 DynamicsCompressorKernel(float sampleRate, unsigned numberOfChannels);
43 void setNumberOfChannels(unsigned);
45 // Performs stereo-linked compression.
46 void process(float* sourceChannels[],
47 float* destinationChannels[],
48 unsigned numberOfChannels,
49 unsigned framesToProcess,
67 unsigned latencyFrames() const { return m_lastPreDelayFrames; }
69 float sampleRate() const { return m_sampleRate; }
74 float m_detectorAverage;
75 float m_compressorGain;
78 float m_meteringReleaseK;
82 enum { MaxPreDelayFrames = 1024 };
83 enum { MaxPreDelayFramesMask = MaxPreDelayFrames - 1 };
84 enum { DefaultPreDelayFrames = 256 }; // setPreDelayTime() will override this initial value
85 unsigned m_lastPreDelayFrames;
86 void setPreDelayTime(float);
88 Vector<OwnPtr<AudioFloatArray> > m_preDelayBuffers;
89 int m_preDelayReadIndex;
90 int m_preDelayWriteIndex;
92 float m_maxAttackCompressionDiffDb;
95 } // namespace WebCore
97 #endif // DynamicsCompressorKernel_h