68 lines
1.8 KiB
C++
68 lines
1.8 KiB
C++
/**********************************************************************
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Audacity: A Digital Audio Editor
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Steve Harris
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Markus Meyer
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**********************************************************************/
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#ifndef __AUDACITY_DITHER_H__
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#define __AUDACITY_DITHER_H__
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#include "SampleFormat.h"
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class Dither
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{
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public:
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/// Default constructor
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Dither();
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/// These ditherers are currently available:
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enum DitherType { none = 0, rectangle = 1, triangle = 2, shaped = 3};
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/// Reset state of the dither.
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void Reset();
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/// Apply the actual dithering. Expects the source sample in the
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/// 'source' variable, the destination sample in the 'dest' variable,
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/// and hints to the formats of the samples. Even if the sample formats
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/// are the same, samples are clipped, if necessary.
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void Apply(DitherType ditherType,
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const samplePtr source, sampleFormat sourceFormat,
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samplePtr dest, sampleFormat destFormat,
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unsigned int len, unsigned int stride = 1);
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private:
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// Dither methods
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float NoDither(float sample);
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float RectangleDither(float sample);
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float TriangleDither(float sample);
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float ShapedDither(float sample);
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// Dither constants
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static const int BUF_SIZE; /* = 8 */
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static const int BUF_MASK; /* = 7 */
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static const float SHAPED_BS[];
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// Dither state
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int mPhase;
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float mTriangleState;
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float mBuffer[8 /* = BUF_SIZE */];
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};
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#endif /* __AUDACITY_DITHER_H__ */
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// Indentation settings for Vim and Emacs and unique identifier for Arch, a
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// version control system. Please do not modify past this point.
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//
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// Local Variables:
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// c-basic-offset: 3
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// indent-tabs-mode: nil
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// End:
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//
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// vim: et sts=3 sw=3
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// arch-tag: 0dabf170-119a-4897-afee-d6fe1ac1a8d6
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