alt_audio_convert.h
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/*
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* Extended Audio Converter for SDL (Simple DirectMedia Layer)
* Copyright (C) 2002 Frank Ranostaj
* Institute of Applied Physik
* Johann Wolfgang Goethe-Universität
* Frankfurt am Main, Germany
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Frank Ranostaj
* ranostaj@stud.uni-frankfurt.de
*
* (This code blatantly abducted for SDL_sound. Thanks, Frank! --ryan.)
*/
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#ifndef _INCLUDE_AUDIO_CONVERT_H_
#define _INCLUDE_AUDIO_CONVERT_H_
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#include "SDL_audio.h"
#define Sound_AI_Loop 0x2
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#define _fsize 32
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typedef struct{
Sint16 numerator;
Sint16 denominator;
} Fraction;
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typedef struct{
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Sint16 c[16][4*_fsize];
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Uint8 incr[16];
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Fraction ratio;
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int mask;
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} VarFilter;
typedef struct{
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Uint8* buffer;
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int mode;
VarFilter *filter;
} AdapterC;
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typedef int (*Adapter) ( AdapterC Data, int length );
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typedef struct{
VarFilter filter;
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int filter_index;
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Adapter adapter[32];
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/* buffer must be len*len_mult(+len_add) big */
int len_mult;
int len_add;
double add;
/* the following elements are provided for compatibility: */
/* the size of the output is approx len*len_ratio */
double len_ratio;
Uint8* buf; /* input/output buffer */
int needed; /* 0 if nothing to be done, 1 otherwise */
int len; /* Length of the input */
int len_cvt; /* Length of converted audio buffer */
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} Sound_AudioCVT;
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#define SDL_SOUND_Loop 0x10
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#ifndef SNDDECLSPEC
#define SNDDECLSPEC DECLSPEC
#endif
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extern SNDDECLSPEC int Sound_ConvertAudio( Sound_AudioCVT *Data );
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extern SNDDECLSPEC int Sound_AltConvertAudio( Sound_AudioCVT *Data,
Uint8* buffer, int length, int mode );
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extern SNDDECLSPEC int Sound_BuildAudioCVT( Sound_AudioCVT *Data,
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Uint16 src_format, Uint8 src_channels, int src_rate,
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Uint16 dst_format, Uint8 dst_channels, int dst_rate, Uint32 bufsize );
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extern SNDDECLSPEC int Sound_AltBuildAudioCVT( Sound_AudioCVT *Data,
SDL_AudioSpec src, SDL_AudioSpec dst );
extern SNDDECLSPEC int Sound_estimateBufferSize( Sound_AudioCVT *Data,
int length );
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#endif /* _INCLUDE_AUDIO_CONVERT_H_ */