SDL_sound_CoreAudio: filter_templates.h annotate

annotate filter_templates.h @ 373:24a610dfbbfd

More altcvt updates from Frank.

author	Ryan C. Gordon <icculus@icculus.org>
date	Sat, 29 Jun 2002 04:08:17 +0000
parents	1b463ef9bcc2
children	44ed8bdeba74

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)*))
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	32
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	33 /-------------------------------------------------------------------------/
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	34 /* this filter (Kaiser-window beta=6.8) gives a decent -80dB attentuation */
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	35 /-------------------------------------------------------------------------/
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	36 #define sum_d(v,dx) ((int) v[CH(dx)] + v[CH(1-dx)])
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	37 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	38 VarFilter* filt, int* cpos )
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	39 {
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	40 int out;
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	41 Sint16 *to;
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	42
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	43 to = inp - length;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	44
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	45 while( inp > to )
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	46 {
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	47 out = 0;
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	48 out-= 9 * sum_d( inp, 16);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	49 out+= 23 * sum_d( inp, 15);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	50 out-= 46 * sum_d( inp, 14);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	51 out+= 83 * sum_d( inp, 13);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	52 out-= 138 * sum_d( inp, 12);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	53 out+= 217 * sum_d( inp, 11);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	54 out-= 326 * sum_d( inp, 10);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	55 out+= 474 * sum_d( inp, 9);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	56 out-= 671 * sum_d( inp, 8);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	57 out+= 936 * sum_d( inp, 7);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	58 out-= 1295 * sum_d( inp, 6);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	59 out+= 1800 * sum_d( inp, 5);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	60 out-= 2560 * sum_d( inp, 4);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	61 out+= 3863 * sum_d( inp, 3);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	62 out-= 6764 * sum_d( inp, 2);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	63 out+= 20798 * sum_d( inp, 1);
338 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 outp[CH(1)] = ( 32770 * inp[CH(1)] + out) >> 16;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	66 outp[CH(0)] = ( 32770 * inp[CH(0)] + out) >> 16;
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	67
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	68 inp -= CH(1);
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	69 outp -= CH(2);
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	70 }
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	71 return outp;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	72 }
373 24a610dfbbfd More altcvt updates from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 371 diff changeset	73 #undef sum_d
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	74
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	75 /-------------------------------------------------------------------------/
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	76 #define sum_h(v,dx) ((int) v[CH(dx)] + v[CH(-dx)])
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	77 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	78 VarFilter* filt, int* cpos )
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	79 {
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	80 int out;
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	81 Sint16* to;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	82
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	83 to = inp + length;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	84
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	85 while( inp < to )
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	86 {
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	87 out = 0;
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	88 out-= 9 * sum_h( inp, 31);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	89 out+= 23 * sum_h( inp, 29);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	90 out-= 46 * sum_h( inp, 27);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	91 out+= 83 * sum_h( inp, 25);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	92 out-= 138 * sum_h( inp, 23);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	93 out+= 217 * sum_h( inp, 21);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	94 out-= 326 * sum_h( inp, 19);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	95 out+= 474 * sum_h( inp, 17);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	96 out-= 671 * sum_h( inp, 15);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	97 out+= 936 * sum_h( inp, 13);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	98 out-= 1295 * sum_h( inp, 11);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	99 out+= 1800 * sum_h( inp, 9);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	100 out-= 2560 * sum_h( inp, 7);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	101 out+= 3863 * sum_h( inp, 5);
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	102 out-= 6764 * sum_h( inp, 3);
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	103 out+= 20798 * sum_h( inp, 1);
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	104 out+= 32770 * (int)inp[0];
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	105
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	106 outp[0] = out >> 16;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	107
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	108 inp+= CH(2);
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	109 outp += CH(1);
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	110 }
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	111 return outp;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	112 }
373 24a610dfbbfd More altcvt updates from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 371 diff changeset	113 #undef sum_h
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	114
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	115 /-------------------------------------------------------------------------/
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	116 static Sint16* Suffix(increaseRate)( Sint16 outp, Sint16 inp, int length,
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	117 VarFilter* filter, int* cpos )
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	118 {
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	119 const static int fsize = CH(2*_fsize);
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	120 Sint16 *f;
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	121 int out;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	122 int i, pos;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	123 Sint16* to;
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	124
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	125 inp -= fsize;
eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	126 to = inp - length;
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	127 pos = *cpos;
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	128
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	129 while( inp > to )
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	130 {
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	131 out = 0;
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	132 f = filter->c[pos];
373 24a610dfbbfd More altcvt updates from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 371 diff changeset	133 for( i = _fsize + 1; --i; inp+=CH(8), f+=4 )
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	134 {
1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	135 out+= f[0] * (int)inp[CH(0)];
373 24a610dfbbfd More altcvt updates from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 371 diff changeset	136 out+= f[1] * (int)inp[CH(2)];
24a610dfbbfd More altcvt updates from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 371 diff changeset	137 out+= f[2] * (int)inp[CH(4)];
24a610dfbbfd More altcvt updates from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 371 diff changeset	138 out+= f[3] * (int)inp[CH(6)];
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	139 }
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	140 outp[0] = out >> 16;
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	141
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	142 pos = ( pos + filter->denominator - 1 ) % filter->denominator;
373 24a610dfbbfd More altcvt updates from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 371 diff changeset	143 inp -= CH( 8 * _fsize );
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	144 inp -= CH( filter->incr[pos] );
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	145 outp -= CH(1);
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	146 }
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	147
1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	148 *cpos = pos;
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	149 return outp;
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	150 }
c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	151
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	152 /-------------------------------------------------------------------------/
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	153 static Sint16* Suffix(decreaseRate)( Sint16 outp, Sint16 inp, int length,
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	154 VarFilter* filter, int* cpos )
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	155 {
366 eda146d666d1 More patches from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 365 diff changeset	156 const static int fsize = CH(2*_fsize);
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	157 Sint16 *f;
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	158 int out;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	159 int i, pos;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	160 Sint16 *to;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	161
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	162 inp -= fsize;
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	163 to = inp + length;
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	164 pos = *cpos;
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	165
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	166 while( inp < to )
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	167 {
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	168 out = 0;
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	169 f = filter->c[pos];
1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	170 for( i = _fsize + 1; --i; inp+=CH(4), f+=4 )
1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	171 {
1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	172 out+= f[0] * (int)inp[CH(0)];
1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	173 out+= f[1] * (int)inp[CH(1)];
1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	174 out+= f[2] * (int)inp[CH(2)];
1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	175 out+= f[3] * (int)inp[CH(3)];
1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	176 }
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	177 outp[0] = out >> 16;
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	178
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	179 inp -= CH( 4 * _fsize );
1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	180 inp += CH( filter->incr[pos] );
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	181 outp += CH(1);
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	182 pos = ( pos + 1 ) % filter->denominator;
362 c7f73428deaf Updated from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 338 diff changeset	183 }
371 1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	184
1b463ef9bcc2 More work from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 366 diff changeset	185 *cpos = pos;
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	186 return outp;
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	187 }
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	188
f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	189 /-------------------------------------------------------------------------/
338 7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	190 #undef CH
7b9a0f3f030e Initial add. Ryan C. Gordon <icculus@icculus.org> parents: diff changeset	191 #endif /* Suffix */
365 f61eadea1f44 More revisions from Frank. Ryan C. Gordon <icculus@icculus.org> parents: 362 diff changeset	192

Mercurial > SDL_sound_CoreAudio

annotate filter_templates.h @ 373:24a610dfbbfd