0,0 → 1,93 |
/* |
* Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com> |
* |
* This file is part of FFmpeg. |
* |
* FFmpeg is free software; you can redistribute it and/or |
* modify it under the terms of the GNU Lesser General Public |
* License as published by the Free Software Foundation; either |
* version 2.1 of the License, or (at your option) any later version. |
* |
* FFmpeg is distributed in the hope that it will be useful, |
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
* Lesser General Public License for more details. |
* |
* You should have received a copy of the GNU Lesser General Public |
* License along with FFmpeg; if not, write to the Free Software |
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
*/ |
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#ifndef AVRESAMPLE_DITHER_H |
#define AVRESAMPLE_DITHER_H |
|
#include "avresample.h" |
#include "audio_data.h" |
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typedef struct DitherContext DitherContext; |
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typedef struct DitherDSPContext { |
/** |
* Convert samples from flt to s16 with added dither noise. |
* |
* @param dst destination float array, range -0.5 to 0.5 |
* @param src source int array, range INT_MIN to INT_MAX. |
* @param dither float dither noise array |
* @param len number of samples |
*/ |
void (*quantize)(int16_t *dst, const float *src, float *dither, int len); |
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int ptr_align; ///< src and dst constraits for quantize() |
int samples_align; ///< len constraits for quantize() |
|
/** |
* Convert dither noise from int to float with triangular distribution. |
* |
* @param dst destination float array, range -0.5 to 0.5 |
* constraints: 32-byte aligned |
* @param src0 source int array, range INT_MIN to INT_MAX. |
* the array size is len * 2 |
* constraints: 32-byte aligned |
* @param len number of output noise samples |
* constraints: multiple of 16 |
*/ |
void (*dither_int_to_float)(float *dst, int *src0, int len); |
} DitherDSPContext; |
|
/** |
* Allocate and initialize a DitherContext. |
* |
* The parameters in the AVAudioResampleContext are used to initialize the |
* DitherContext. |
* |
* @param avr AVAudioResampleContext |
* @return newly-allocated DitherContext |
*/ |
DitherContext *ff_dither_alloc(AVAudioResampleContext *avr, |
enum AVSampleFormat out_fmt, |
enum AVSampleFormat in_fmt, |
int channels, int sample_rate, int apply_map); |
|
/** |
* Free a DitherContext. |
* |
* @param c DitherContext |
*/ |
void ff_dither_free(DitherContext **c); |
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/** |
* Convert audio sample format with dithering. |
* |
* @param c DitherContext |
* @param dst destination audio data |
* @param src source audio data |
* @return 0 if ok, negative AVERROR code on failure |
*/ |
int ff_convert_dither(DitherContext *c, AudioData *dst, AudioData *src); |
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/* arch-specific initialization functions */ |
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void ff_dither_init_x86(DitherDSPContext *ddsp, |
enum AVResampleDitherMethod method); |
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#endif /* AVRESAMPLE_DITHER_H */ |