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author | Guido van Rossum <guido@python.org> | 1992-06-01 16:01:24 (GMT) |
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committer | Guido van Rossum <guido@python.org> | 1992-06-01 16:01:24 (GMT) |
commit | b66efa0d750dab70b793ba72e779d9ce6998a36e (patch) | |
tree | cc6c14f7ee91ca126a24a5423e37264383b3c97a /Modules/audioop.c | |
parent | 1c34fc7afbb0e551ff9373968c18d5c4c099a50f (diff) | |
download | cpython-b66efa0d750dab70b793ba72e779d9ce6998a36e.zip cpython-b66efa0d750dab70b793ba72e779d9ce6998a36e.tar.gz cpython-b66efa0d750dab70b793ba72e779d9ce6998a36e.tar.bz2 |
Initial revision
Diffstat (limited to 'Modules/audioop.c')
-rw-r--r-- | Modules/audioop.c | 574 |
1 files changed, 574 insertions, 0 deletions
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"); +} |