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1343 lines
36 KiB
C
1343 lines
36 KiB
C
/***********************************************************
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Copyright 1991, 1992, 1993 by Stichting Mathematisch Centrum,
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Amsterdam, The Netherlands.
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All Rights Reserved
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Permission to use, copy, modify, and distribute this software and its
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documentation for any purpose and without fee is hereby granted,
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provided that the above copyright notice appear in all copies and that
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both that copyright notice and this permission notice appear in
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supporting documentation, and that the names of Stichting Mathematisch
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Centrum or CWI not be used in advertising or publicity pertaining to
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distribution of the software without specific, written prior permission.
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STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
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THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
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FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
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FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
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OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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******************************************************************/
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/* audioopmodele - Module to detect peak values in arrays */
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#ifdef sun
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#define signed
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#endif
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#include <math.h>
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#include "allobjects.h"
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#include "modsupport.h"
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/* Code shamelessly stolen from sox,
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** (c) Craig Reese, Joe Campbell and Jeff Poskanzer 1989 */
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#define MINLIN -32768
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#define MAXLIN 32767
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#define LINCLIP(x) do { if ( x < MINLIN ) x = MINLIN ; else if ( x > MAXLIN ) x = MAXLIN; } while ( 0 )
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unsigned char st_linear_to_ulaw( /* int sample */ );
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/*
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** This macro converts from ulaw to 16 bit linear, faster.
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**
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** Jef Poskanzer
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** 23 October 1989
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**
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** Input: 8 bit ulaw sample
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** Output: signed 16 bit linear sample
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*/
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#define st_ulaw_to_linear(ulawbyte) ulaw_table[ulawbyte]
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static int ulaw_table[256] = {
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-32124, -31100, -30076, -29052, -28028, -27004, -25980, -24956,
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-23932, -22908, -21884, -20860, -19836, -18812, -17788, -16764,
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-15996, -15484, -14972, -14460, -13948, -13436, -12924, -12412,
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-11900, -11388, -10876, -10364, -9852, -9340, -8828, -8316,
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-7932, -7676, -7420, -7164, -6908, -6652, -6396, -6140,
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-5884, -5628, -5372, -5116, -4860, -4604, -4348, -4092,
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-3900, -3772, -3644, -3516, -3388, -3260, -3132, -3004,
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-2876, -2748, -2620, -2492, -2364, -2236, -2108, -1980,
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-1884, -1820, -1756, -1692, -1628, -1564, -1500, -1436,
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-1372, -1308, -1244, -1180, -1116, -1052, -988, -924,
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-876, -844, -812, -780, -748, -716, -684, -652,
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-620, -588, -556, -524, -492, -460, -428, -396,
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-372, -356, -340, -324, -308, -292, -276, -260,
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-244, -228, -212, -196, -180, -164, -148, -132,
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-120, -112, -104, -96, -88, -80, -72, -64,
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-56, -48, -40, -32, -24, -16, -8, 0,
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32124, 31100, 30076, 29052, 28028, 27004, 25980, 24956,
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23932, 22908, 21884, 20860, 19836, 18812, 17788, 16764,
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15996, 15484, 14972, 14460, 13948, 13436, 12924, 12412,
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11900, 11388, 10876, 10364, 9852, 9340, 8828, 8316,
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7932, 7676, 7420, 7164, 6908, 6652, 6396, 6140,
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5884, 5628, 5372, 5116, 4860, 4604, 4348, 4092,
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3900, 3772, 3644, 3516, 3388, 3260, 3132, 3004,
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2876, 2748, 2620, 2492, 2364, 2236, 2108, 1980,
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1884, 1820, 1756, 1692, 1628, 1564, 1500, 1436,
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1372, 1308, 1244, 1180, 1116, 1052, 988, 924,
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876, 844, 812, 780, 748, 716, 684, 652,
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620, 588, 556, 524, 492, 460, 428, 396,
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372, 356, 340, 324, 308, 292, 276, 260,
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244, 228, 212, 196, 180, 164, 148, 132,
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120, 112, 104, 96, 88, 80, 72, 64,
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56, 48, 40, 32, 24, 16, 8, 0 };
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#define ZEROTRAP /* turn on the trap as per the MIL-STD */
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#define BIAS 0x84 /* define the add-in bias for 16 bit samples */
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#define CLIP 32635
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unsigned char
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st_linear_to_ulaw( sample )
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int sample;
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{
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static int exp_lut[256] = {0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,
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4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
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5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
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5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
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6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
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6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
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6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
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6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
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7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
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7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
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7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
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7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
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7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
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7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
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7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
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7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7};
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int sign, exponent, mantissa;
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unsigned char ulawbyte;
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/* Get the sample into sign-magnitude. */
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sign = (sample >> 8) & 0x80; /* set aside the sign */
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if ( sign != 0 ) sample = -sample; /* get magnitude */
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if ( sample > CLIP ) sample = CLIP; /* clip the magnitude */
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/* Convert from 16 bit linear to ulaw. */
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sample = sample + BIAS;
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exponent = exp_lut[( sample >> 7 ) & 0xFF];
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mantissa = ( sample >> ( exponent + 3 ) ) & 0x0F;
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ulawbyte = ~ ( sign | ( exponent << 4 ) | mantissa );
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#ifdef ZEROTRAP
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if ( ulawbyte == 0 ) ulawbyte = 0x02; /* optional CCITT trap */
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#endif
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return ulawbyte;
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}
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/* End of code taken from sox */
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/* ADPCM-3 step variation table */
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static float newstep[5] = { 0.8, 0.9, 1.0, 1.75, 1.75 };
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/* Intel ADPCM step variation table */
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static int indexTable[16] = {
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-1, -1, -1, -1, 2, 4, 6, 8,
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-1, -1, -1, -1, 2, 4, 6, 8,
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};
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static int stepsizeTable[89] = {
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7, 8, 9, 10, 11, 12, 13, 14, 16, 17,
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19, 21, 23, 25, 28, 31, 34, 37, 41, 45,
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50, 55, 60, 66, 73, 80, 88, 97, 107, 118,
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130, 143, 157, 173, 190, 209, 230, 253, 279, 307,
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337, 371, 408, 449, 494, 544, 598, 658, 724, 796,
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876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066,
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2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358,
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5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
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15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767
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};
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#define CHARP(cp, i) ((signed char *)(cp+i))
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#define SHORTP(cp, i) ((short *)(cp+i))
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#define LONGP(cp, i) ((long *)(cp+i))
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static object *AudioopError;
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static object *
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audioop_getsample(self, args)
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object *self;
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object *args;
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{
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signed char *cp;
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int len, size, val;
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int i;
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if ( !getargs(args, "(s#ii)", &cp, &len, &size, &i) )
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return 0;
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if ( size != 1 && size != 2 && size != 4 ) {
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err_setstr(AudioopError, "Size should be 1, 2 or 4");
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return 0;
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}
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if ( i < 0 || i >= len/size ) {
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err_setstr(AudioopError, "Index out of range");
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return 0;
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}
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if ( size == 1 ) val = (int)*CHARP(cp, i);
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else if ( size == 2 ) val = (int)*SHORTP(cp, i*2);
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else if ( size == 4 ) val = (int)*LONGP(cp, i*4);
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return newintobject(val);
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}
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static object *
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audioop_max(self, args)
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object *self;
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object *args;
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{
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signed char *cp;
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int len, size, val;
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int i;
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int max = 0;
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if ( !getargs(args, "(s#i)", &cp, &len, &size) )
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return 0;
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if ( size != 1 && size != 2 && size != 4 ) {
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err_setstr(AudioopError, "Size should be 1, 2 or 4");
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return 0;
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}
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for ( i=0; i<len; i+= size) {
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if ( size == 1 ) val = (int)*CHARP(cp, i);
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else if ( size == 2 ) val = (int)*SHORTP(cp, i);
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else if ( size == 4 ) val = (int)*LONGP(cp, i);
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if ( val < 0 ) val = (-val);
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if ( val > max ) max = val;
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}
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return newintobject(max);
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}
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static object *
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audioop_avg(self, args)
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object *self;
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object *args;
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{
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signed char *cp;
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int len, size, val;
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int i;
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float avg = 0.0;
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if ( !getargs(args, "(s#i)", &cp, &len, &size) )
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return 0;
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if ( size != 1 && size != 2 && size != 4 ) {
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err_setstr(AudioopError, "Size should be 1, 2 or 4");
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return 0;
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}
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for ( i=0; i<len; i+= size) {
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if ( size == 1 ) val = (int)*CHARP(cp, i);
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else if ( size == 2 ) val = (int)*SHORTP(cp, i);
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else if ( size == 4 ) val = (int)*LONGP(cp, i);
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avg += val;
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}
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if ( len == 0 )
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val = 0;
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else
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val = (int)(avg / (float)(len/size));
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return newintobject(val);
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}
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static object *
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audioop_rms(self, args)
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object *self;
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object *args;
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{
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signed char *cp;
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int len, size, val;
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int i;
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float sum_squares = 0.0;
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if ( !getargs(args, "(s#i)", &cp, &len, &size) )
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return 0;
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if ( size != 1 && size != 2 && size != 4 ) {
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err_setstr(AudioopError, "Size should be 1, 2 or 4");
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return 0;
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}
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for ( i=0; i<len; i+= size) {
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if ( size == 1 ) val = (int)*CHARP(cp, i);
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else if ( size == 2 ) val = (int)*SHORTP(cp, i);
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else if ( size == 4 ) val = (int)*LONGP(cp, i);
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sum_squares += (float)val*(float)val;
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}
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if ( len == 0 )
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val = 0;
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else
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val = (int)sqrt(sum_squares / (float)(len/size));
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return newintobject(val);
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}
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double _sum2(a, b, len)
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short *a;
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short *b;
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int len;
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{
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int i;
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double sum = 0.0;
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for( i=0; i<len; i++) {
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sum = sum + (double)a[i]*(double)b[i];
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}
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return sum;
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}
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/*
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** Findfit tries to locate a sample within another sample. Its main use
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** is in echo-cancellation (to find the feedback of the output signal in
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** the input signal).
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** The method used is as follows:
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**
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** let R be the reference signal (length n) and A the input signal (length N)
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** with N > n, and let all sums be over i from 0 to n-1.
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**
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** Now, for each j in {0..N-n} we compute a factor fj so that -fj*R matches A
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** as good as possible, i.e. sum( (A[j+i]+fj*R[i])^2 ) is minimal. This
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** equation gives fj = sum( A[j+i]R[i] ) / sum(R[i]^2).
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**
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** Next, we compute the relative distance between the original signal and
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** the modified signal and minimize that over j:
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** vj = sum( (A[j+i]-fj*R[i])^2 ) / sum( A[j+i]^2 ) =>
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** vj = ( sum(A[j+i]^2)*sum(R[i]^2) - sum(A[j+i]R[i])^2 ) / sum( A[j+i]^2 )
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**
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** In the code variables correspond as follows:
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** cp1 A
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** cp2 R
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** len1 N
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** len2 n
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** aj_m1 A[j-1]
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** aj_lm1 A[j+n-1]
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** sum_ri_2 sum(R[i]^2)
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** sum_aij_2 sum(A[i+j]^2)
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** sum_aij_ri sum(A[i+j]R[i])
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**
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** sum_ri is calculated once, sum_aij_2 is updated each step and sum_aij_ri
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** is completely recalculated each step.
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*/
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static object *
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audioop_findfit(self, args)
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object *self;
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object *args;
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{
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short *cp1, *cp2;
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int len1, len2;
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int j, best_j;
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double aj_m1, aj_lm1;
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double sum_ri_2, sum_aij_2, sum_aij_ri, result, best_result, factor;
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if ( !getargs(args, "(s#s#)", &cp1, &len1, &cp2, &len2) )
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return 0;
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if ( len1 & 1 || len2 & 1 ) {
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err_setstr(AudioopError, "Strings should be even-sized");
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return 0;
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}
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len1 >>= 1;
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len2 >>= 1;
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if ( len1 < len2 ) {
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err_setstr(AudioopError, "First sample should be longer");
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return 0;
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}
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sum_ri_2 = _sum2(cp2, cp2, len2);
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sum_aij_2 = _sum2(cp1, cp1, len2);
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sum_aij_ri = _sum2(cp1, cp2, len2);
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result = (sum_ri_2*sum_aij_2 - sum_aij_ri*sum_aij_ri) / sum_aij_2;
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best_result = result;
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best_j = 0;
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j = 0;
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for ( j=1; j<=len1-len2; j++) {
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aj_m1 = (double)cp1[j-1];
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aj_lm1 = (double)cp1[j+len2-1];
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sum_aij_2 = sum_aij_2 + aj_lm1*aj_lm1 - aj_m1*aj_m1;
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sum_aij_ri = _sum2(cp1+j, cp2, len2);
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result = (sum_ri_2*sum_aij_2 - sum_aij_ri*sum_aij_ri) / sum_aij_2;
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if ( result < best_result ) {
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best_result = result;
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best_j = j;
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}
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}
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factor = _sum2(cp1+best_j, cp2, len2) / sum_ri_2;
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return mkvalue("(if)", best_j, factor);
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}
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/*
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** findfactor finds a factor f so that the energy in A-fB is minimal.
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** See the comment for findfit for details.
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*/
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static object *
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audioop_findfactor(self, args)
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object *self;
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object *args;
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{
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short *cp1, *cp2;
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int len1, len2;
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double sum_ri_2, sum_aij_ri, result;
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if ( !getargs(args, "(s#s#)", &cp1, &len1, &cp2, &len2) )
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return 0;
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if ( len1 & 1 || len2 & 1 ) {
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err_setstr(AudioopError, "Strings should be even-sized");
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return 0;
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}
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if ( len1 != len2 ) {
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err_setstr(AudioopError, "Samples should be same size");
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return 0;
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}
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len2 >>= 1;
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sum_ri_2 = _sum2(cp2, cp2, len2);
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sum_aij_ri = _sum2(cp1, cp2, len2);
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result = sum_aij_ri / sum_ri_2;
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return newfloatobject(result);
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}
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/*
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** findmax returns the index of the n-sized segment of the input sample
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** that contains the most energy.
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*/
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static object *
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audioop_findmax(self, args)
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object *self;
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object *args;
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{
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short *cp1;
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int len1, len2;
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int j, best_j;
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double aj_m1, aj_lm1;
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double result, best_result;
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if ( !getargs(args, "(s#i)", &cp1, &len1, &len2) )
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return 0;
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if ( len1 & 1 ) {
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err_setstr(AudioopError, "Strings should be even-sized");
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return 0;
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}
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len1 >>= 1;
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if ( len1 < len2 ) {
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err_setstr(AudioopError, "Input sample should be longer");
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return 0;
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}
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result = _sum2(cp1, cp1, len2);
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best_result = result;
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best_j = 0;
|
|
j = 0;
|
|
|
|
for ( j=1; j<=len1-len2; j++) {
|
|
aj_m1 = (double)cp1[j-1];
|
|
aj_lm1 = (double)cp1[j+len2-1];
|
|
|
|
result = result + aj_lm1*aj_lm1 - aj_m1*aj_m1;
|
|
|
|
if ( result > best_result ) {
|
|
best_result = result;
|
|
best_j = j;
|
|
}
|
|
|
|
}
|
|
|
|
return newintobject(best_j);
|
|
}
|
|
|
|
static object *
|
|
audioop_avgpp(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp;
|
|
int len, size, val, prevval, prevextremevalid = 0, prevextreme;
|
|
int i;
|
|
float avg = 0.0;
|
|
int diff, prevdiff, extremediff, nextreme = 0;
|
|
|
|
if ( !getargs(args, "(s#i)", &cp, &len, &size) )
|
|
return 0;
|
|
if ( size != 1 && size != 2 && size != 4 ) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
/* Compute first delta value ahead. Also automatically makes us
|
|
** skip the first extreme value
|
|
*/
|
|
if ( size == 1 ) prevval = (int)*CHARP(cp, 0);
|
|
else if ( size == 2 ) prevval = (int)*SHORTP(cp, 0);
|
|
else if ( size == 4 ) prevval = (int)*LONGP(cp, 0);
|
|
if ( size == 1 ) val = (int)*CHARP(cp, size);
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, size);
|
|
else if ( size == 4 ) val = (int)*LONGP(cp, size);
|
|
prevdiff = val - prevval;
|
|
|
|
for ( i=size; i<len; i+= size) {
|
|
if ( size == 1 ) val = (int)*CHARP(cp, i);
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, i);
|
|
else if ( size == 4 ) val = (int)*LONGP(cp, i);
|
|
diff = val - prevval;
|
|
if ( diff*prevdiff < 0 ) {
|
|
/* Derivative changed sign. Compute difference to last extreme
|
|
** value and remember.
|
|
*/
|
|
if ( prevextremevalid ) {
|
|
extremediff = prevval - prevextreme;
|
|
if ( extremediff < 0 )
|
|
extremediff = -extremediff;
|
|
avg += extremediff;
|
|
nextreme++;
|
|
}
|
|
prevextremevalid = 1;
|
|
prevextreme = prevval;
|
|
}
|
|
prevval = val;
|
|
if ( diff != 0 )
|
|
prevdiff = diff;
|
|
}
|
|
if ( nextreme == 0 )
|
|
val = 0;
|
|
else
|
|
val = (int)(avg / (float)nextreme);
|
|
return newintobject(val);
|
|
}
|
|
|
|
static object *
|
|
audioop_maxpp(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp;
|
|
int len, size, val, prevval, prevextremevalid = 0, prevextreme;
|
|
int i;
|
|
int max = 0;
|
|
int diff, prevdiff, extremediff;
|
|
|
|
if ( !getargs(args, "(s#i)", &cp, &len, &size) )
|
|
return 0;
|
|
if ( size != 1 && size != 2 && size != 4 ) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
/* Compute first delta value ahead. Also automatically makes us
|
|
** skip the first extreme value
|
|
*/
|
|
if ( size == 1 ) prevval = (int)*CHARP(cp, 0);
|
|
else if ( size == 2 ) prevval = (int)*SHORTP(cp, 0);
|
|
else if ( size == 4 ) prevval = (int)*LONGP(cp, 0);
|
|
if ( size == 1 ) val = (int)*CHARP(cp, size);
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, size);
|
|
else if ( size == 4 ) val = (int)*LONGP(cp, size);
|
|
prevdiff = val - prevval;
|
|
|
|
for ( i=size; i<len; i+= size) {
|
|
if ( size == 1 ) val = (int)*CHARP(cp, i);
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, i);
|
|
else if ( size == 4 ) val = (int)*LONGP(cp, i);
|
|
diff = val - prevval;
|
|
if ( diff*prevdiff < 0 ) {
|
|
/* Derivative changed sign. Compute difference to last extreme
|
|
** value and remember.
|
|
*/
|
|
if ( prevextremevalid ) {
|
|
extremediff = prevval - prevextreme;
|
|
if ( extremediff < 0 )
|
|
extremediff = -extremediff;
|
|
if ( extremediff > max )
|
|
max = extremediff;
|
|
}
|
|
prevextremevalid = 1;
|
|
prevextreme = prevval;
|
|
}
|
|
prevval = val;
|
|
if ( diff != 0 )
|
|
prevdiff = diff;
|
|
}
|
|
return newintobject(max);
|
|
}
|
|
|
|
static object *
|
|
audioop_cross(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp;
|
|
int len, size, val;
|
|
int i;
|
|
int cross, prevval, ncross;
|
|
|
|
if ( !getargs(args, "(s#i)", &cp, &len, &size) )
|
|
return 0;
|
|
if ( size != 1 && size != 2 && size != 4 ) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
ncross = -1;
|
|
prevval = 17; /* Anything <> 0,1 */
|
|
for ( i=0; i<len; i+= size) {
|
|
if ( size == 1 ) val = ((int)*CHARP(cp, i)) >> 7;
|
|
else if ( size == 2 ) val = ((int)*SHORTP(cp, i)) >> 15;
|
|
else if ( size == 4 ) val = ((int)*LONGP(cp, i)) >> 31;
|
|
val = val & 1;
|
|
if ( val != prevval ) ncross++;
|
|
prevval = val;
|
|
}
|
|
return newintobject(ncross);
|
|
}
|
|
|
|
static object *
|
|
audioop_mul(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp, *ncp;
|
|
int len, size, val;
|
|
double factor, fval, maxval;
|
|
object *rv;
|
|
int i;
|
|
|
|
if ( !getargs(args, "(s#id)", &cp, &len, &size, &factor ) )
|
|
return 0;
|
|
|
|
if ( size == 1 ) maxval = (double) 0x7f;
|
|
else if ( size == 2 ) maxval = (double) 0x7fff;
|
|
else if ( size == 4 ) maxval = (double) 0x7fffffff;
|
|
else {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
rv = newsizedstringobject(NULL, len);
|
|
if ( rv == 0 )
|
|
return 0;
|
|
ncp = (signed char *)getstringvalue(rv);
|
|
|
|
|
|
for ( i=0; i < len; i += size ) {
|
|
if ( size == 1 ) val = (int)*CHARP(cp, i);
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, i);
|
|
else if ( size == 4 ) val = (int)*LONGP(cp, i);
|
|
fval = (double)val*factor;
|
|
if ( fval > maxval ) fval = maxval;
|
|
else if ( fval < -maxval ) fval = -maxval;
|
|
val = (int)fval;
|
|
if ( size == 1 ) *CHARP(ncp, i) = (signed char)val;
|
|
else if ( size == 2 ) *SHORTP(ncp, i) = (short)val;
|
|
else if ( size == 4 ) *LONGP(ncp, i) = (long)val;
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_tomono(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp, *ncp;
|
|
int len, size, val1, val2;
|
|
double fac1, fac2, fval, maxval;
|
|
object *rv;
|
|
int i;
|
|
|
|
if ( !getargs(args, "(s#idd)", &cp, &len, &size, &fac1, &fac2 ) )
|
|
return 0;
|
|
|
|
if ( size == 1 ) maxval = (double) 0x7f;
|
|
else if ( size == 2 ) maxval = (double) 0x7fff;
|
|
else if ( size == 4 ) maxval = (double) 0x7fffffff;
|
|
else {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
rv = newsizedstringobject(NULL, len/2);
|
|
if ( rv == 0 )
|
|
return 0;
|
|
ncp = (signed char *)getstringvalue(rv);
|
|
|
|
|
|
for ( i=0; i < len; i += size*2 ) {
|
|
if ( size == 1 ) val1 = (int)*CHARP(cp, i);
|
|
else if ( size == 2 ) val1 = (int)*SHORTP(cp, i);
|
|
else if ( size == 4 ) val1 = (int)*LONGP(cp, i);
|
|
if ( size == 1 ) val2 = (int)*CHARP(cp, i+1);
|
|
else if ( size == 2 ) val2 = (int)*SHORTP(cp, i+2);
|
|
else if ( size == 4 ) val2 = (int)*LONGP(cp, i+4);
|
|
fval = (double)val1*fac1 + (double)val2*fac2;
|
|
if ( fval > maxval ) fval = maxval;
|
|
else if ( fval < -maxval ) fval = -maxval;
|
|
val1 = (int)fval;
|
|
if ( size == 1 ) *CHARP(ncp, i/2) = (signed char)val1;
|
|
else if ( size == 2 ) *SHORTP(ncp, i/2) = (short)val1;
|
|
else if ( size == 4 ) *LONGP(ncp, i/2)= (long)val1;
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_tostereo(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp, *ncp;
|
|
int len, size, val1, val2, val;
|
|
double fac1, fac2, fval, maxval;
|
|
object *rv;
|
|
int i;
|
|
|
|
if ( !getargs(args, "(s#idd)", &cp, &len, &size, &fac1, &fac2 ) )
|
|
return 0;
|
|
|
|
if ( size == 1 ) maxval = (double) 0x7f;
|
|
else if ( size == 2 ) maxval = (double) 0x7fff;
|
|
else if ( size == 4 ) maxval = (double) 0x7fffffff;
|
|
else {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
rv = newsizedstringobject(NULL, len*2);
|
|
if ( rv == 0 )
|
|
return 0;
|
|
ncp = (signed char *)getstringvalue(rv);
|
|
|
|
|
|
for ( i=0; i < len; i += size ) {
|
|
if ( size == 1 ) val = (int)*CHARP(cp, i);
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, i);
|
|
else if ( size == 4 ) val = (int)*LONGP(cp, i);
|
|
|
|
fval = (double)val*fac1;
|
|
if ( fval > maxval ) fval = maxval;
|
|
else if ( fval < -maxval ) fval = -maxval;
|
|
val1 = (int)fval;
|
|
|
|
fval = (double)val*fac2;
|
|
if ( fval > maxval ) fval = maxval;
|
|
else if ( fval < -maxval ) fval = -maxval;
|
|
val2 = (int)fval;
|
|
|
|
if ( size == 1 ) *CHARP(ncp, i*2) = (signed char)val1;
|
|
else if ( size == 2 ) *SHORTP(ncp, i*2) = (short)val1;
|
|
else if ( size == 4 ) *LONGP(ncp, i*2) = (long)val1;
|
|
|
|
if ( size == 1 ) *CHARP(ncp, i*2+1) = (signed char)val2;
|
|
else if ( size == 2 ) *SHORTP(ncp, i*2+2) = (short)val2;
|
|
else if ( size == 4 ) *LONGP(ncp, i*2+4) = (long)val2;
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_add(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp1, *cp2, *ncp;
|
|
int len1, len2, size, val1, val2;
|
|
object *rv;
|
|
int i;
|
|
|
|
if ( !getargs(args, "(s#s#i)",
|
|
&cp1, &len1, &cp2, &len2, &size ) )
|
|
return 0;
|
|
|
|
if ( len1 != len2 ) {
|
|
err_setstr(AudioopError, "Lengths should be the same");
|
|
return 0;
|
|
}
|
|
|
|
if ( size != 1 && size != 2 && size != 4) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
rv = newsizedstringobject(NULL, len1);
|
|
if ( rv == 0 )
|
|
return 0;
|
|
ncp = (signed char *)getstringvalue(rv);
|
|
|
|
|
|
for ( i=0; i < len1; i += size ) {
|
|
if ( size == 1 ) val1 = (int)*CHARP(cp1, i);
|
|
else if ( size == 2 ) val1 = (int)*SHORTP(cp1, i);
|
|
else if ( size == 4 ) val1 = (int)*LONGP(cp1, i);
|
|
|
|
if ( size == 1 ) val2 = (int)*CHARP(cp2, i);
|
|
else if ( size == 2 ) val2 = (int)*SHORTP(cp2, i);
|
|
else if ( size == 4 ) val2 = (int)*LONGP(cp2, i);
|
|
|
|
if ( size == 1 ) *CHARP(ncp, i) = (signed char)(val1+val2);
|
|
else if ( size == 2 ) *SHORTP(ncp, i) = (short)(val1+val2);
|
|
else if ( size == 4 ) *LONGP(ncp, i) = (long)(val1+val2);
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_bias(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp, *ncp;
|
|
int len, size, val;
|
|
object *rv;
|
|
int i;
|
|
int bias;
|
|
|
|
if ( !getargs(args, "(s#ii)",
|
|
&cp, &len, &size , &bias) )
|
|
return 0;
|
|
|
|
if ( size != 1 && size != 2 && size != 4) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
rv = newsizedstringobject(NULL, len);
|
|
if ( rv == 0 )
|
|
return 0;
|
|
ncp = (signed char *)getstringvalue(rv);
|
|
|
|
|
|
for ( i=0; i < len; i += size ) {
|
|
if ( size == 1 ) val = (int)*CHARP(cp, i);
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, i);
|
|
else if ( size == 4 ) val = (int)*LONGP(cp, i);
|
|
|
|
if ( size == 1 ) *CHARP(ncp, i) = (signed char)(val+bias);
|
|
else if ( size == 2 ) *SHORTP(ncp, i) = (short)(val+bias);
|
|
else if ( size == 4 ) *LONGP(ncp, i) = (long)(val+bias);
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_reverse(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp;
|
|
unsigned char *ncp;
|
|
int len, size, val;
|
|
object *rv;
|
|
int i, j;
|
|
|
|
if ( !getargs(args, "(s#i)",
|
|
&cp, &len, &size) )
|
|
return 0;
|
|
|
|
if ( size != 1 && size != 2 && size != 4 ) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
rv = newsizedstringobject(NULL, len);
|
|
if ( rv == 0 )
|
|
return 0;
|
|
ncp = (unsigned char *)getstringvalue(rv);
|
|
|
|
for ( i=0; i < len; i += size ) {
|
|
if ( size == 1 ) val = ((int)*CHARP(cp, i)) << 8;
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, i);
|
|
else if ( size == 4 ) val = ((int)*LONGP(cp, i)) >> 16;
|
|
|
|
j = len - i - size;
|
|
|
|
if ( size == 1 ) *CHARP(ncp, j) = (signed char)(val >> 8);
|
|
else if ( size == 2 ) *SHORTP(ncp, j) = (short)(val);
|
|
else if ( size == 4 ) *LONGP(ncp, j) = (long)(val<<16);
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_lin2lin(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp;
|
|
unsigned char *ncp;
|
|
int len, size, size2, val;
|
|
object *rv;
|
|
int i, j;
|
|
|
|
if ( !getargs(args, "(s#ii)",
|
|
&cp, &len, &size, &size2) )
|
|
return 0;
|
|
|
|
if ( (size != 1 && size != 2 && size != 4) ||
|
|
(size2 != 1 && size2 != 2 && size2 != 4)) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
rv = newsizedstringobject(NULL, (len/size)*size2);
|
|
if ( rv == 0 )
|
|
return 0;
|
|
ncp = (unsigned char *)getstringvalue(rv);
|
|
|
|
for ( i=0, j=0; i < len; i += size, j += size2 ) {
|
|
if ( size == 1 ) val = ((int)*CHARP(cp, i)) << 8;
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, i);
|
|
else if ( size == 4 ) val = ((int)*LONGP(cp, i)) >> 16;
|
|
|
|
if ( size2 == 1 ) *CHARP(ncp, j) = (signed char)(val >> 8);
|
|
else if ( size2 == 2 ) *SHORTP(ncp, j) = (short)(val);
|
|
else if ( size2 == 4 ) *LONGP(ncp, j) = (long)(val<<16);
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_lin2ulaw(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp;
|
|
unsigned char *ncp;
|
|
int len, size, val;
|
|
object *rv;
|
|
int i;
|
|
|
|
if ( !getargs(args, "(s#i)",
|
|
&cp, &len, &size) )
|
|
return 0;
|
|
|
|
if ( size != 1 && size != 2 && size != 4) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
rv = newsizedstringobject(NULL, len/size);
|
|
if ( rv == 0 )
|
|
return 0;
|
|
ncp = (unsigned char *)getstringvalue(rv);
|
|
|
|
for ( i=0; i < len; i += size ) {
|
|
if ( size == 1 ) val = ((int)*CHARP(cp, i)) << 8;
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, i);
|
|
else if ( size == 4 ) val = ((int)*LONGP(cp, i)) >> 16;
|
|
|
|
*ncp++ = st_linear_to_ulaw(val);
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_ulaw2lin(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
unsigned char *cp;
|
|
unsigned char cval;
|
|
signed char *ncp;
|
|
int len, size, val;
|
|
object *rv;
|
|
int i;
|
|
|
|
if ( !getargs(args, "(s#i)",
|
|
&cp, &len, &size) )
|
|
return 0;
|
|
|
|
if ( size != 1 && size != 2 && size != 4) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
rv = newsizedstringobject(NULL, len*size);
|
|
if ( rv == 0 )
|
|
return 0;
|
|
ncp = (signed char *)getstringvalue(rv);
|
|
|
|
for ( i=0; i < len*size; i += size ) {
|
|
cval = *cp++;
|
|
val = st_ulaw_to_linear(cval);
|
|
|
|
if ( size == 1 ) *CHARP(ncp, i) = (signed char)(val >> 8);
|
|
else if ( size == 2 ) *SHORTP(ncp, i) = (short)(val);
|
|
else if ( size == 4 ) *LONGP(ncp, i) = (long)(val<<16);
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_lin2adpcm3(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp;
|
|
signed char *ncp;
|
|
int len, size, val, step, valprev, delta;
|
|
object *rv, *state, *str;
|
|
int i;
|
|
|
|
if ( !getargs(args, "(s#iO)",
|
|
&cp, &len, &size, &state) )
|
|
return 0;
|
|
|
|
|
|
if ( size != 1 && size != 2 && size != 4) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
str = newsizedstringobject(NULL, len/size);
|
|
if ( str == 0 )
|
|
return 0;
|
|
ncp = (signed char *)getstringvalue(str);
|
|
|
|
/* Decode state, should have (value, step) */
|
|
if ( state == None ) {
|
|
/* First time, it seems. Set defaults */
|
|
valprev = 0;
|
|
step = 4; /* The '4' is magic. Dunno it's significance */
|
|
} else if ( !getargs(state, "(ii)", &valprev, &step) )
|
|
return 0;
|
|
|
|
for ( i=0; i < len; i += size ) {
|
|
if ( size == 1 ) val = ((int)*CHARP(cp, i)) << 8;
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, i);
|
|
else if ( size == 4 ) val = ((int)*LONGP(cp, i)) >> 16;
|
|
|
|
/* Step 1 - compute difference with previous value */
|
|
delta = (val - valprev)/step;
|
|
|
|
/* Step 2 - Clamp */
|
|
if ( delta < -4 )
|
|
delta = -4;
|
|
else if ( delta > 3 )
|
|
delta = 3;
|
|
|
|
/* Step 3 - Update previous value */
|
|
valprev += delta*step;
|
|
|
|
/* Step 4 - Clamp previous value to 16 bits */
|
|
if ( valprev > 32767 )
|
|
valprev = 32767;
|
|
else if ( valprev < -32768 )
|
|
valprev = -32768;
|
|
|
|
/* Step 5 - Update step value */
|
|
step = step * newstep[abs(delta)];
|
|
step++; /* Don't understand this. */
|
|
|
|
/* Step 6 - Output value (as a whole byte, currently) */
|
|
*ncp++ = delta;
|
|
}
|
|
rv = mkvalue("(O(ii))", str, valprev, step);
|
|
DECREF(str);
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_adpcm32lin(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp;
|
|
signed char *ncp;
|
|
int len, size, val, valprev, step, delta;
|
|
object *rv, *str, *state;
|
|
int i;
|
|
|
|
if ( !getargs(args, "(s#iO)",
|
|
&cp, &len, &size, &state) )
|
|
return 0;
|
|
|
|
if ( size != 1 && size != 2 && size != 4) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
/* Decode state, should have (value, step) */
|
|
if ( state == None ) {
|
|
/* First time, it seems. Set defaults */
|
|
valprev = 0;
|
|
step = 4; /* The '4' is magic. Dunno it's significance */
|
|
} else if ( !getargs(state, "(ii)", &valprev, &step) )
|
|
return 0;
|
|
|
|
str = newsizedstringobject(NULL, len*size);
|
|
if ( str == 0 )
|
|
return 0;
|
|
ncp = (signed char *)getstringvalue(str);
|
|
|
|
for ( i=0; i < len*size; i += size ) {
|
|
/* Step 1 - get the delta value */
|
|
delta = *cp++;
|
|
|
|
/* Step 2 - update output value */
|
|
valprev = valprev + delta*step;
|
|
|
|
/* Step 3 - clamp output value */
|
|
if ( valprev > 32767 )
|
|
valprev = 32767;
|
|
else if ( valprev < -32768 )
|
|
valprev = -32768;
|
|
|
|
/* Step 4 - Update step value */
|
|
step = step * newstep[abs(delta)];
|
|
step++;
|
|
|
|
/* Step 5 - Output value */
|
|
if ( size == 1 ) *CHARP(ncp, i) = (signed char)(valprev >> 8);
|
|
else if ( size == 2 ) *SHORTP(ncp, i) = (short)(valprev);
|
|
else if ( size == 4 ) *LONGP(ncp, i) = (long)(valprev<<16);
|
|
}
|
|
|
|
rv = mkvalue("(O(ii))", str, valprev, step);
|
|
DECREF(str);
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_lin2adpcm(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp;
|
|
signed char *ncp;
|
|
int len, size, val, step, valpred, delta, index, sign, vpdiff, diff;
|
|
object *rv, *state, *str;
|
|
int i, outputbuffer, bufferstep;
|
|
|
|
if ( !getargs(args, "(s#iO)",
|
|
&cp, &len, &size, &state) )
|
|
return 0;
|
|
|
|
|
|
if ( size != 1 && size != 2 && size != 4) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
str = newsizedstringobject(NULL, len/(size*2));
|
|
if ( str == 0 )
|
|
return 0;
|
|
ncp = (signed char *)getstringvalue(str);
|
|
|
|
/* Decode state, should have (value, step) */
|
|
if ( state == None ) {
|
|
/* First time, it seems. Set defaults */
|
|
valpred = 0;
|
|
step = 7;
|
|
index = 0;
|
|
} else if ( !getargs(state, "(ii)", &valpred, &index) )
|
|
return 0;
|
|
|
|
step = stepsizeTable[index];
|
|
bufferstep = 1;
|
|
|
|
for ( i=0; i < len; i += size ) {
|
|
if ( size == 1 ) val = ((int)*CHARP(cp, i)) << 8;
|
|
else if ( size == 2 ) val = (int)*SHORTP(cp, i);
|
|
else if ( size == 4 ) val = ((int)*LONGP(cp, i)) >> 16;
|
|
|
|
/* Step 1 - compute difference with previous value */
|
|
diff = val - valpred;
|
|
sign = (diff < 0) ? 8 : 0;
|
|
if ( sign ) diff = (-diff);
|
|
|
|
/* Step 2 - Divide and clamp */
|
|
/* Note:
|
|
** This code *approximately* computes:
|
|
** delta = diff*4/step;
|
|
** vpdiff = (delta+0.5)*step/4;
|
|
** but in shift step bits are dropped. The net result of this is
|
|
** that even if you have fast mul/div hardware you cannot put it to
|
|
** good use since the fixup would be too expensive.
|
|
*/
|
|
delta = 0;
|
|
vpdiff = (step >> 3);
|
|
|
|
if ( diff >= step ) {
|
|
delta = 4;
|
|
diff -= step;
|
|
vpdiff += step;
|
|
}
|
|
step >>= 1;
|
|
if ( diff >= step ) {
|
|
delta |= 2;
|
|
diff -= step;
|
|
vpdiff += step;
|
|
}
|
|
step >>= 1;
|
|
if ( diff >= step ) {
|
|
delta |= 1;
|
|
vpdiff += step;
|
|
}
|
|
|
|
/* Step 3 - Update previous value */
|
|
if ( sign )
|
|
valpred -= vpdiff;
|
|
else
|
|
valpred += vpdiff;
|
|
|
|
/* Step 4 - Clamp previous value to 16 bits */
|
|
if ( valpred > 32767 )
|
|
valpred = 32767;
|
|
else if ( valpred < -32768 )
|
|
valpred = -32768;
|
|
|
|
/* Step 5 - Assemble value, update index and step values */
|
|
delta |= sign;
|
|
|
|
index += indexTable[delta];
|
|
if ( index < 0 ) index = 0;
|
|
if ( index > 88 ) index = 88;
|
|
step = stepsizeTable[index];
|
|
|
|
/* Step 6 - Output value */
|
|
if ( bufferstep ) {
|
|
outputbuffer = (delta << 4) & 0xf0;
|
|
} else {
|
|
*ncp++ = (delta & 0x0f) | outputbuffer;
|
|
}
|
|
bufferstep = !bufferstep;
|
|
}
|
|
rv = mkvalue("(O(ii))", str, valpred, index);
|
|
DECREF(str);
|
|
return rv;
|
|
}
|
|
|
|
static object *
|
|
audioop_adpcm2lin(self, args)
|
|
object *self;
|
|
object *args;
|
|
{
|
|
signed char *cp;
|
|
signed char *ncp;
|
|
int len, size, val, valpred, step, delta, index, sign, vpdiff;
|
|
object *rv, *str, *state;
|
|
int i, inputbuffer, bufferstep;
|
|
|
|
if ( !getargs(args, "(s#iO)",
|
|
&cp, &len, &size, &state) )
|
|
return 0;
|
|
|
|
if ( size != 1 && size != 2 && size != 4) {
|
|
err_setstr(AudioopError, "Size should be 1, 2 or 4");
|
|
return 0;
|
|
}
|
|
|
|
/* Decode state, should have (value, step) */
|
|
if ( state == None ) {
|
|
/* First time, it seems. Set defaults */
|
|
valpred = 0;
|
|
step = 7;
|
|
index = 0;
|
|
} else if ( !getargs(state, "(ii)", &valpred, &index) )
|
|
return 0;
|
|
|
|
str = newsizedstringobject(NULL, len*size*2);
|
|
if ( str == 0 )
|
|
return 0;
|
|
ncp = (signed char *)getstringvalue(str);
|
|
|
|
step = stepsizeTable[index];
|
|
bufferstep = 0;
|
|
|
|
for ( i=0; i < len*size*2; i += size ) {
|
|
/* Step 1 - get the delta value and compute next index */
|
|
if ( bufferstep ) {
|
|
delta = inputbuffer & 0xf;
|
|
} else {
|
|
inputbuffer = *cp++;
|
|
delta = (inputbuffer >> 4) & 0xf;
|
|
}
|
|
|
|
bufferstep = !bufferstep;
|
|
|
|
/* Step 2 - Find new index value (for later) */
|
|
index += indexTable[delta];
|
|
if ( index < 0 ) index = 0;
|
|
if ( index > 88 ) index = 88;
|
|
|
|
/* Step 3 - Separate sign and magnitude */
|
|
sign = delta & 8;
|
|
delta = delta & 7;
|
|
|
|
/* Step 4 - Compute difference and new predicted value */
|
|
/*
|
|
** Computes 'vpdiff = (delta+0.5)*step/4', but see comment
|
|
** in adpcm_coder.
|
|
*/
|
|
vpdiff = step >> 3;
|
|
if ( delta & 4 ) vpdiff += step;
|
|
if ( delta & 2 ) vpdiff += step>>1;
|
|
if ( delta & 1 ) vpdiff += step>>2;
|
|
|
|
if ( sign )
|
|
valpred -= vpdiff;
|
|
else
|
|
valpred += vpdiff;
|
|
|
|
/* Step 5 - clamp output value */
|
|
if ( valpred > 32767 )
|
|
valpred = 32767;
|
|
else if ( valpred < -32768 )
|
|
valpred = -32768;
|
|
|
|
/* Step 6 - Update step value */
|
|
step = stepsizeTable[index];
|
|
|
|
/* Step 6 - Output value */
|
|
if ( size == 1 ) *CHARP(ncp, i) = (signed char)(valpred >> 8);
|
|
else if ( size == 2 ) *SHORTP(ncp, i) = (short)(valpred);
|
|
else if ( size == 4 ) *LONGP(ncp, i) = (long)(valpred<<16);
|
|
}
|
|
|
|
rv = mkvalue("(O(ii))", str, valpred, index);
|
|
DECREF(str);
|
|
return rv;
|
|
}
|
|
|
|
static struct methodlist audioop_methods[] = {
|
|
{ "max", audioop_max },
|
|
{ "avg", audioop_avg },
|
|
{ "maxpp", audioop_maxpp },
|
|
{ "avgpp", audioop_avgpp },
|
|
{ "rms", audioop_rms },
|
|
{ "findfit", audioop_findfit },
|
|
{ "findmax", audioop_findmax },
|
|
{ "findfactor", audioop_findfactor },
|
|
{ "cross", audioop_cross },
|
|
{ "mul", audioop_mul },
|
|
{ "add", audioop_add },
|
|
{ "bias", audioop_bias },
|
|
{ "ulaw2lin", audioop_ulaw2lin },
|
|
{ "lin2ulaw", audioop_lin2ulaw },
|
|
{ "lin2lin", audioop_lin2lin },
|
|
{ "adpcm2lin", audioop_adpcm2lin },
|
|
{ "lin2adpcm", audioop_lin2adpcm },
|
|
{ "adpcm32lin", audioop_adpcm32lin },
|
|
{ "lin2adpcm3", audioop_lin2adpcm3 },
|
|
{ "tomono", audioop_tomono },
|
|
{ "tostereo", audioop_tostereo },
|
|
{ "getsample", audioop_getsample },
|
|
{ "reverse", audioop_reverse },
|
|
{ 0, 0 }
|
|
};
|
|
|
|
|
|
void
|
|
initaudioop()
|
|
{
|
|
object *m, *d;
|
|
m = initmodule("audioop", audioop_methods);
|
|
d = getmoduledict(m);
|
|
AudioopError = newstringobject("audioop.error");
|
|
if ( AudioopError == NULL || dictinsert(d,"error",AudioopError) )
|
|
fatal("can't define audioop.error");
|
|
}
|