SDL_sound_CoreAudio: filter_templates.h annotate

annotate filter_templates.h @ 365:f61eadea1f44

More revisions from Frank.

author	Ryan C. Gordon <icculus@icculus.org>
date	Tue, 18 Jun 2002 21:49:44 +0000
parents	c7f73428deaf
children	eda146d666d1

rev	line source
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	1 /*
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	2 * Extended Audio Converter for SDL (Simple DirectMedia Layer)
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	3 * Copyright (C) 2002 Frank Ranostaj
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	4 * Institute of Applied Physik
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	5 * Johann Wolfgang Goethe-Universität
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	6 * Frankfurt am Main, Germany
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	7 *
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	8 * This library is free software; you can redistribute it and/or
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	9 * modify it under the terms of the GNU Library General Public
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	10 * License as published by the Free Software Foundation; either
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	11 * version 2 of the License, or (at your option) any later version.
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	12 *
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	13 * This library is distributed in the hope that it will be useful,
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	16 * Library General Public License for more details.
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	17 *
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	18 * You should have received a copy of the GNU Library General Public
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	19 * License along with this library; if not, write to the Free
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	21 *
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	22 * Frank Ranostaj
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	23 * ranostaj@stud.uni-frankfurt.de
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	24 *
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	25 * (This code blatantly abducted for SDL_sound. Thanks, Frank! --ryan.)
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	26 */
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	27
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	28 #ifndef Suffix
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	29 #error include filter_template.h with defined Suffix macro!
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	30 #else
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	31 #define CH(x) (Suffix((x)*))
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	32 /-------------------------------------------------------------------------/
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	33 /*
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	34 * !!! FIXME !!!
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	35 *
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	36 *
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	37 * Tune doubleRate(), halfRate() and varRate() for speed
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	38 * - Frank
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	39 */
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	40
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	41 /-------------------------------------------------------------------------/
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	42 static Sint16* Suffix(doubleRate)( Sint16 outp, Sint16 inp, int length,
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	43 VarFilter* filt, int* cpos )
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	44 {
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	45 static const int fsize = _fsize;
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	46 int i, out;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	47 Sint16* to;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	48
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	49 inp += fsize;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	50 to = inp + length;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	51
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	52 for(; inp > to; inp -= CH(1) )
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	53 {
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	54 out = 0;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	55 for( i = 1; i < 1+fsize; i++ )
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	56 out+= filter[2i] ( inp[CH(i)] + inp[CH(1-i)] );
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	57
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	58 outp[CH(1)] = ( 32770 * inp[CH(1)] + out) >> 16;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	59 outp[CH(0)] = ( 32770 * inp[CH(0)] + out) >> 16;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	60 outp -= CH(2);
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	61 }
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	62 return outp;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	63 }
7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	64
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	65 /-------------------------------------------------------------------------/
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	66 static Sint16* Suffix(halfRate)( Sint16 outp, Sint16 inp, int length,
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	67 VarFilter* filt, int* cpos )
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	68 {
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	69 static const int fsize = CH(_fsize/2);
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	70 int i, out;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	71 Sint16* to;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	72
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	73 inp -= fsize;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	74 to = inp + length;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	75
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	76 for(; inp < to; inp+= CH(2) )
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	77 {
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	78 out = 32770 * inp[0];
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	79 for( i = 1; i < fsize/2; i+=2 )
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	80 out+= filter[i]*( (int)inp[CH(i)] + inp[CH(-i)] );
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	81 outp[0] = out >> 16;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	82
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	83 outp += CH(1);
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	84 }
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	85 return outp;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	86 }
7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	87
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	88 /-------------------------------------------------------------------------/
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	89 static Sint16* Suffix(increaseRate)( Sint16 outp, Sint16 inp, int length,
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	90 VarFilter* filt, int* cpos )
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	91 {
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	92 const static int fsize = 2*_fsize;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	93 Sint16 *filter;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	94 int out;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	95 int i, pos;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	96 Sint16* to;
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	97
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	98 inp += fsize;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	99 to = inp + length;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	100
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	101 while( inp > to )
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	102 {
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	103 pos = *cpos;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	104 out = 0;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	105 filter = filt->c[pos];
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	106 for( i = 0; i < 2*_fsize; i++ )
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	107 out+= filter[i] * (int)inp[CH(i)];
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	108 outp[0] = out >> 16;
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	109
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	110 inp -= CH(filt->incr[pos]);
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	111 outp -= CH(1);
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	112 *cpos = ( pos + 1 ) % filt->denominator;
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	113 }
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	114 return outp;
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	115 }
c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	116
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	117 /-------------------------------------------------------------------------/
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	118 static Sint16* Suffix(decreaseRate)( Sint16 outp, Sint16 inp, int length,
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	119 VarFilter* filt, int* cpos )
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	120 {
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	121 const static int fsize = 2*_fsize;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	122 Sint16 *filter;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	123 int out;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	124 int i, pos;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	125 Sint16 *to;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	126
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	127 inp -= fsize;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	128 to = inp + length;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	129
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	130 while( inp < to )
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	131 {
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	132 pos = *cpos;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	133 out = 0;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	134 filter = filt->c[pos];
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	135 for( i = 0; i < 2*_fsize; i++ )
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	136 out+= filter[i] * (int)inp[CH(i)];
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	137 outp[0] = out >> 16;
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	138
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	139 inp += CH(filt->incr[pos]);
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	140 outp += CH(1);
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	141 *cpos = ( pos + 1 ) % filt->denominator;
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	142 }
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	143 return outp;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	144 }
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	145
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	146 /-------------------------------------------------------------------------/
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	147 #undef CH
7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	148 #endif /* Suffix */
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	149

Mercurial > SDL_sound_CoreAudio

annotate filter_templates.h @ 365:f61eadea1f44