Initial revision
diff --git a/Modules/audioop.c b/Modules/audioop.c
new file mode 100644
index 0000000..2718b49
--- /dev/null
+++ b/Modules/audioop.c
@@ -0,0 +1,574 @@
+/***********************************************************
+Copyright 1991 by Stichting Mathematisch Centrum, Amsterdam, The
+Netherlands.
+
+ All Rights Reserved
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in
+supporting documentation, and that the names of Stichting Mathematisch
+Centrum or CWI not be used in advertising or publicity pertaining to
+distribution of the software without specific, written prior permission.
+
+STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
+THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
+FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+******************************************************************/
+
+/* audioopmodele - Module to detect peak values in arrays */
+
+#ifdef sun
+#define signed
+#endif
+
+#include "allobjects.h"
+#include "modsupport.h"
+
+/* Code shamelessly stealen from sox,
+** (c) Craig Reese, Joe Campbell and Jeff Poskanzer 1989 */
+
+#define MINLIN -32768
+#define MAXLIN 32767
+#define LINCLIP(x) do { if ( x < MINLIN ) x = MINLIN ; else if ( x > MAXLIN ) x = MAXLIN; } while ( 0 )
+
+unsigned char st_linear_to_ulaw( /* int sample */ );
+
+/*
+** This macro converts from ulaw to 16 bit linear, faster.
+**
+** Jef Poskanzer
+** 23 October 1989
+**
+** Input: 8 bit ulaw sample
+** Output: signed 16 bit linear sample
+*/
+#define st_ulaw_to_linear(ulawbyte) ulaw_table[ulawbyte]
+
+static int ulaw_table[256] = {
+ -32124, -31100, -30076, -29052, -28028, -27004, -25980, -24956,
+ -23932, -22908, -21884, -20860, -19836, -18812, -17788, -16764,
+ -15996, -15484, -14972, -14460, -13948, -13436, -12924, -12412,
+ -11900, -11388, -10876, -10364, -9852, -9340, -8828, -8316,
+ -7932, -7676, -7420, -7164, -6908, -6652, -6396, -6140,
+ -5884, -5628, -5372, -5116, -4860, -4604, -4348, -4092,
+ -3900, -3772, -3644, -3516, -3388, -3260, -3132, -3004,
+ -2876, -2748, -2620, -2492, -2364, -2236, -2108, -1980,
+ -1884, -1820, -1756, -1692, -1628, -1564, -1500, -1436,
+ -1372, -1308, -1244, -1180, -1116, -1052, -988, -924,
+ -876, -844, -812, -780, -748, -716, -684, -652,
+ -620, -588, -556, -524, -492, -460, -428, -396,
+ -372, -356, -340, -324, -308, -292, -276, -260,
+ -244, -228, -212, -196, -180, -164, -148, -132,
+ -120, -112, -104, -96, -88, -80, -72, -64,
+ -56, -48, -40, -32, -24, -16, -8, 0,
+ 32124, 31100, 30076, 29052, 28028, 27004, 25980, 24956,
+ 23932, 22908, 21884, 20860, 19836, 18812, 17788, 16764,
+ 15996, 15484, 14972, 14460, 13948, 13436, 12924, 12412,
+ 11900, 11388, 10876, 10364, 9852, 9340, 8828, 8316,
+ 7932, 7676, 7420, 7164, 6908, 6652, 6396, 6140,
+ 5884, 5628, 5372, 5116, 4860, 4604, 4348, 4092,
+ 3900, 3772, 3644, 3516, 3388, 3260, 3132, 3004,
+ 2876, 2748, 2620, 2492, 2364, 2236, 2108, 1980,
+ 1884, 1820, 1756, 1692, 1628, 1564, 1500, 1436,
+ 1372, 1308, 1244, 1180, 1116, 1052, 988, 924,
+ 876, 844, 812, 780, 748, 716, 684, 652,
+ 620, 588, 556, 524, 492, 460, 428, 396,
+ 372, 356, 340, 324, 308, 292, 276, 260,
+ 244, 228, 212, 196, 180, 164, 148, 132,
+ 120, 112, 104, 96, 88, 80, 72, 64,
+ 56, 48, 40, 32, 24, 16, 8, 0 };
+
+#define ZEROTRAP /* turn on the trap as per the MIL-STD */
+#define BIAS 0x84 /* define the add-in bias for 16 bit samples */
+#define CLIP 32635
+
+unsigned char
+st_linear_to_ulaw( sample )
+int sample;
+ {
+ static int exp_lut[256] = {0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,
+ 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
+ 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
+ 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
+ 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+ 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+ 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+ 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+ 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7};
+ int sign, exponent, mantissa;
+ unsigned char ulawbyte;
+
+ /* Get the sample into sign-magnitude. */
+ sign = (sample >> 8) & 0x80; /* set aside the sign */
+ if ( sign != 0 ) sample = -sample; /* get magnitude */
+ if ( sample > CLIP ) sample = CLIP; /* clip the magnitude */
+
+ /* Convert from 16 bit linear to ulaw. */
+ sample = sample + BIAS;
+ exponent = exp_lut[( sample >> 7 ) & 0xFF];
+ mantissa = ( sample >> ( exponent + 3 ) ) & 0x0F;
+ ulawbyte = ~ ( sign | ( exponent << 4 ) | mantissa );
+#ifdef ZEROTRAP
+ if ( ulawbyte == 0 ) ulawbyte = 0x02; /* optional CCITT trap */
+#endif
+
+ return ulawbyte;
+ }
+/* End of code taken from sox */
+
+#define CHARP(cp, i) ((signed char *)(cp+i))
+#define SHORTP(cp, i) ((short *)(cp+i))
+#define LONGP(cp, i) ((long *)(cp+i))
+
+
+
+static object *AudioopError;
+
+static object *
+audioop_getsample(self, args)
+ object *self;
+ object *args;
+{
+ signed char *cp;
+ int len, size, val;
+ int i;
+
+ if ( !getargs(args, "(s#ii)", &cp, &len, &size, &i) )
+ return 0;
+ if ( size != 1 && size != 2 && size != 4 ) {
+ err_setstr(AudioopError, "Size should be 1, 2 or 4");
+ return 0;
+ }
+ if ( i < 0 || i >= len/size ) {
+ err_setstr(AudioopError, "Index out of range");
+ return 0;
+ }
+ if ( size == 1 ) val = (int)*CHARP(cp, i);
+ else if ( size == 2 ) val = (int)*SHORTP(cp, i*2);
+ else if ( size == 4 ) val = (int)*LONGP(cp, i*4);
+ return newintobject(val);
+}
+
+static object *
+audioop_max(self, args)
+ object *self;
+ object *args;
+{
+ signed char *cp;
+ int len, size, val;
+ int i;
+ int max = 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;
+ }
+ 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 ( val < 0 ) val = (-val);
+ if ( val > max ) max = val;
+ }
+ return newintobject(max);
+}
+
+static object *
+audioop_avg(self, args)
+ object *self;
+ object *args;
+{
+ signed char *cp;
+ int len, size, val;
+ int i;
+ float avg = 0.0;
+
+ 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;
+ }
+ 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);
+ avg += val;
+ }
+ if ( len == 0 )
+ val = 0;
+ else
+ val = (int)(avg / (float)(len/size));
+ return newintobject(val);
+}
+
+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_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 struct methodlist audioop_methods[] = {
+ { "max", audioop_max },
+ { "avg", audioop_avg },
+ { "cross", audioop_cross },
+ { "mul", audioop_mul },
+ { "add", audioop_add },
+ { "bias", audioop_bias },
+ { "ulaw2lin", audioop_ulaw2lin },
+ { "lin2ulaw", audioop_lin2ulaw },
+ { "tomono", audioop_tomono },
+ { "tostereo", audioop_tostereo },
+ { "getsample", audioop_getsample },
+ { 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");
+}