diff -r ffa851df0825 -r 2fb8b9db1c86 symbian-qemu-0.9.1-12/python-2.6.1/Modules/audioop.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/symbian-qemu-0.9.1-12/python-2.6.1/Modules/audioop.c Fri Jul 31 15:01:17 2009 +0100 @@ -0,0 +1,1655 @@ + +/* audioopmodule - Module to detect peak values in arrays */ + +#include "Python.h" + +#if SIZEOF_INT == 4 +typedef int Py_Int32; +typedef unsigned int Py_UInt32; +#else +#if SIZEOF_LONG == 4 +typedef long Py_Int32; +typedef unsigned long Py_UInt32; +#else +#error "No 4-byte integral type" +#endif +#endif + +typedef short PyInt16; + +#if defined(__CHAR_UNSIGNED__) +#if defined(signed) +/* This module currently does not work on systems where only unsigned + characters are available. Take it out of Setup. Sorry. */ +#endif +#endif + +/* Code shamelessly stolen from sox, 12.17.7, g711.c +** (c) Craig Reese, Joe Campbell and Jeff Poskanzer 1989 */ + +/* From g711.c: + * + * December 30, 1994: + * Functions linear2alaw, linear2ulaw have been updated to correctly + * convert unquantized 16 bit values. + * Tables for direct u- to A-law and A- to u-law conversions have been + * corrected. + * Borge Lindberg, Center for PersonKommunikation, Aalborg University. + * bli@cpk.auc.dk + * + */ +#define BIAS 0x84 /* define the add-in bias for 16 bit samples */ +#define CLIP 32635 +#define SIGN_BIT (0x80) /* Sign bit for a A-law byte. */ +#define QUANT_MASK (0xf) /* Quantization field mask. */ +#define SEG_SHIFT (4) /* Left shift for segment number. */ +#define SEG_MASK (0x70) /* Segment field mask. */ + +static PyInt16 seg_aend[8] = {0x1F, 0x3F, 0x7F, 0xFF, + 0x1FF, 0x3FF, 0x7FF, 0xFFF}; +static PyInt16 seg_uend[8] = {0x3F, 0x7F, 0xFF, 0x1FF, + 0x3FF, 0x7FF, 0xFFF, 0x1FFF}; + +static PyInt16 +search(PyInt16 val, PyInt16 *table, int size) +{ + int i; + + for (i = 0; i < size; i++) { + if (val <= *table++) + return (i); + } + return (size); +} +#define st_ulaw2linear16(uc) (_st_ulaw2linear16[uc]) +#define st_alaw2linear16(uc) (_st_alaw2linear16[uc]) + +static PyInt16 _st_ulaw2linear16[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 +}; + +/* + * linear2ulaw() accepts a 14-bit signed integer and encodes it as u-law data + * stored in a unsigned char. This function should only be called with + * the data shifted such that it only contains information in the lower + * 14-bits. + * + * In order to simplify the encoding process, the original linear magnitude + * is biased by adding 33 which shifts the encoding range from (0 - 8158) to + * (33 - 8191). The result can be seen in the following encoding table: + * + * Biased Linear Input Code Compressed Code + * ------------------------ --------------- + * 00000001wxyza 000wxyz + * 0000001wxyzab 001wxyz + * 000001wxyzabc 010wxyz + * 00001wxyzabcd 011wxyz + * 0001wxyzabcde 100wxyz + * 001wxyzabcdef 101wxyz + * 01wxyzabcdefg 110wxyz + * 1wxyzabcdefgh 111wxyz + * + * Each biased linear code has a leading 1 which identifies the segment + * number. The value of the segment number is equal to 7 minus the number + * of leading 0's. The quantization interval is directly available as the + * four bits wxyz. * The trailing bits (a - h) are ignored. + * + * Ordinarily the complement of the resulting code word is used for + * transmission, and so the code word is complemented before it is returned. + * + * For further information see John C. Bellamy's Digital Telephony, 1982, + * John Wiley & Sons, pps 98-111 and 472-476. + */ +static unsigned char +st_14linear2ulaw(PyInt16 pcm_val) /* 2's complement (14-bit range) */ +{ + PyInt16 mask; + PyInt16 seg; + unsigned char uval; + + /* The original sox code does this in the calling function, not here */ + pcm_val = pcm_val >> 2; + + /* u-law inverts all bits */ + /* Get the sign and the magnitude of the value. */ + if (pcm_val < 0) { + pcm_val = -pcm_val; + mask = 0x7F; + } else { + mask = 0xFF; + } + if ( pcm_val > CLIP ) pcm_val = CLIP; /* clip the magnitude */ + pcm_val += (BIAS >> 2); + + /* Convert the scaled magnitude to segment number. */ + seg = search(pcm_val, seg_uend, 8); + + /* + * Combine the sign, segment, quantization bits; + * and complement the code word. + */ + if (seg >= 8) /* out of range, return maximum value. */ + return (unsigned char) (0x7F ^ mask); + else { + uval = (unsigned char) (seg << 4) | ((pcm_val >> (seg + 1)) & 0xF); + return (uval ^ mask); + } + +} + +static PyInt16 _st_alaw2linear16[256] = { + -5504, -5248, -6016, -5760, -4480, -4224, -4992, + -4736, -7552, -7296, -8064, -7808, -6528, -6272, + -7040, -6784, -2752, -2624, -3008, -2880, -2240, + -2112, -2496, -2368, -3776, -3648, -4032, -3904, + -3264, -3136, -3520, -3392, -22016, -20992, -24064, + -23040, -17920, -16896, -19968, -18944, -30208, -29184, + -32256, -31232, -26112, -25088, -28160, -27136, -11008, + -10496, -12032, -11520, -8960, -8448, -9984, -9472, + -15104, -14592, -16128, -15616, -13056, -12544, -14080, + -13568, -344, -328, -376, -360, -280, -264, + -312, -296, -472, -456, -504, -488, -408, + -392, -440, -424, -88, -72, -120, -104, + -24, -8, -56, -40, -216, -200, -248, + -232, -152, -136, -184, -168, -1376, -1312, + -1504, -1440, -1120, -1056, -1248, -1184, -1888, + -1824, -2016, -1952, -1632, -1568, -1760, -1696, + -688, -656, -752, -720, -560, -528, -624, + -592, -944, -912, -1008, -976, -816, -784, + -880, -848, 5504, 5248, 6016, 5760, 4480, + 4224, 4992, 4736, 7552, 7296, 8064, 7808, + 6528, 6272, 7040, 6784, 2752, 2624, 3008, + 2880, 2240, 2112, 2496, 2368, 3776, 3648, + 4032, 3904, 3264, 3136, 3520, 3392, 22016, + 20992, 24064, 23040, 17920, 16896, 19968, 18944, + 30208, 29184, 32256, 31232, 26112, 25088, 28160, + 27136, 11008, 10496, 12032, 11520, 8960, 8448, + 9984, 9472, 15104, 14592, 16128, 15616, 13056, + 12544, 14080, 13568, 344, 328, 376, 360, + 280, 264, 312, 296, 472, 456, 504, + 488, 408, 392, 440, 424, 88, 72, + 120, 104, 24, 8, 56, 40, 216, + 200, 248, 232, 152, 136, 184, 168, + 1376, 1312, 1504, 1440, 1120, 1056, 1248, + 1184, 1888, 1824, 2016, 1952, 1632, 1568, + 1760, 1696, 688, 656, 752, 720, 560, + 528, 624, 592, 944, 912, 1008, 976, + 816, 784, 880, 848 +}; + +/* + * linear2alaw() accepts an 13-bit signed integer and encodes it as A-law data + * stored in a unsigned char. This function should only be called with + * the data shifted such that it only contains information in the lower + * 13-bits. + * + * Linear Input Code Compressed Code + * ------------------------ --------------- + * 0000000wxyza 000wxyz + * 0000001wxyza 001wxyz + * 000001wxyzab 010wxyz + * 00001wxyzabc 011wxyz + * 0001wxyzabcd 100wxyz + * 001wxyzabcde 101wxyz + * 01wxyzabcdef 110wxyz + * 1wxyzabcdefg 111wxyz + * + * For further information see John C. Bellamy's Digital Telephony, 1982, + * John Wiley & Sons, pps 98-111 and 472-476. + */ +static unsigned char +st_linear2alaw(PyInt16 pcm_val) /* 2's complement (13-bit range) */ +{ + PyInt16 mask; + short seg; + unsigned char aval; + + /* The original sox code does this in the calling function, not here */ + pcm_val = pcm_val >> 3; + + /* A-law using even bit inversion */ + if (pcm_val >= 0) { + mask = 0xD5; /* sign (7th) bit = 1 */ + } else { + mask = 0x55; /* sign bit = 0 */ + pcm_val = -pcm_val - 1; + } + + /* Convert the scaled magnitude to segment number. */ + seg = search(pcm_val, seg_aend, 8); + + /* Combine the sign, segment, and quantization bits. */ + + if (seg >= 8) /* out of range, return maximum value. */ + return (unsigned char) (0x7F ^ mask); + else { + aval = (unsigned char) seg << SEG_SHIFT; + if (seg < 2) + aval |= (pcm_val >> 1) & QUANT_MASK; + else + aval |= (pcm_val >> seg) & QUANT_MASK; + return (aval ^ mask); + } +} +/* End of code taken from sox */ + +/* Intel ADPCM step variation table */ +static int indexTable[16] = { + -1, -1, -1, -1, 2, 4, 6, 8, + -1, -1, -1, -1, 2, 4, 6, 8, +}; + +static int stepsizeTable[89] = { + 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, + 19, 21, 23, 25, 28, 31, 34, 37, 41, 45, + 50, 55, 60, 66, 73, 80, 88, 97, 107, 118, + 130, 143, 157, 173, 190, 209, 230, 253, 279, 307, + 337, 371, 408, 449, 494, 544, 598, 658, 724, 796, + 876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066, + 2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358, + 5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899, + 15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767 +}; + +#define CHARP(cp, i) ((signed char *)(cp+i)) +#define SHORTP(cp, i) ((short *)(cp+i)) +#define LONGP(cp, i) ((Py_Int32 *)(cp+i)) + + + +static PyObject *AudioopError; + +static PyObject * +audioop_getsample(PyObject *self, PyObject *args) +{ + signed char *cp; + int len, size, val = 0; + int i; + + if ( !PyArg_ParseTuple(args, "s#ii:getsample", &cp, &len, &size, &i) ) + return 0; + if ( size != 1 && size != 2 && size != 4 ) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + if ( i < 0 || i >= len/size ) { + PyErr_SetString(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 PyInt_FromLong(val); +} + +static PyObject * +audioop_max(PyObject *self, PyObject *args) +{ + signed char *cp; + int len, size, val = 0; + int i; + int max = 0; + + if ( !PyArg_ParseTuple(args, "s#i:max", &cp, &len, &size) ) + return 0; + if ( size != 1 && size != 2 && size != 4 ) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + for ( i=0; i max ) max = val; + } + return PyInt_FromLong(max); +} + +static PyObject * +audioop_minmax(PyObject *self, PyObject *args) +{ + signed char *cp; + int len, size, val = 0; + int i; + int min = 0x7fffffff, max = -0x7fffffff; + + if (!PyArg_ParseTuple(args, "s#i:minmax", &cp, &len, &size)) + return NULL; + if (size != 1 && size != 2 && size != 4) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return NULL; + } + 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 > max) max = val; + if (val < min) min = val; + } + return Py_BuildValue("(ii)", min, max); +} + +static PyObject * +audioop_avg(PyObject *self, PyObject *args) +{ + signed char *cp; + int len, size, val = 0; + int i; + double avg = 0.0; + + if ( !PyArg_ParseTuple(args, "s#i:avg", &cp, &len, &size) ) + return 0; + if ( size != 1 && size != 2 && size != 4 ) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + for ( i=0; i n, and let all sums be over i from 0 to n-1. +** +** Now, for each j in {0..N-n} we compute a factor fj so that -fj*R matches A +** as good as possible, i.e. sum( (A[j+i]+fj*R[i])^2 ) is minimal. This +** equation gives fj = sum( A[j+i]R[i] ) / sum(R[i]^2). +** +** Next, we compute the relative distance between the original signal and +** the modified signal and minimize that over j: +** vj = sum( (A[j+i]-fj*R[i])^2 ) / sum( A[j+i]^2 ) => +** vj = ( sum(A[j+i]^2)*sum(R[i]^2) - sum(A[j+i]R[i])^2 ) / sum( A[j+i]^2 ) +** +** In the code variables correspond as follows: +** cp1 A +** cp2 R +** len1 N +** len2 n +** aj_m1 A[j-1] +** aj_lm1 A[j+n-1] +** sum_ri_2 sum(R[i]^2) +** sum_aij_2 sum(A[i+j]^2) +** sum_aij_ri sum(A[i+j]R[i]) +** +** sum_ri is calculated once, sum_aij_2 is updated each step and sum_aij_ri +** is completely recalculated each step. +*/ +static PyObject * +audioop_findfit(PyObject *self, PyObject *args) +{ + short *cp1, *cp2; + int len1, len2; + int j, best_j; + double aj_m1, aj_lm1; + double sum_ri_2, sum_aij_2, sum_aij_ri, result, best_result, factor; + + /* Passing a short** for an 's' argument is correct only + if the string contents is aligned for interpretation + as short[]. Due to the definition of PyStringObject, + this is currently (Python 2.6) the case. */ + if ( !PyArg_ParseTuple(args, "s#s#:findfit", + (char**)&cp1, &len1, (char**)&cp2, &len2) ) + return 0; + if ( len1 & 1 || len2 & 1 ) { + PyErr_SetString(AudioopError, "Strings should be even-sized"); + return 0; + } + len1 >>= 1; + len2 >>= 1; + + if ( len1 < len2 ) { + PyErr_SetString(AudioopError, "First sample should be longer"); + return 0; + } + sum_ri_2 = _sum2(cp2, cp2, len2); + sum_aij_2 = _sum2(cp1, cp1, len2); + sum_aij_ri = _sum2(cp1, cp2, len2); + + result = (sum_ri_2*sum_aij_2 - sum_aij_ri*sum_aij_ri) / sum_aij_2; + + best_result = result; + 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]; + + sum_aij_2 = sum_aij_2 + aj_lm1*aj_lm1 - aj_m1*aj_m1; + sum_aij_ri = _sum2(cp1+j, cp2, len2); + + result = (sum_ri_2*sum_aij_2 - sum_aij_ri*sum_aij_ri) + / sum_aij_2; + + if ( result < best_result ) { + best_result = result; + best_j = j; + } + + } + + factor = _sum2(cp1+best_j, cp2, len2) / sum_ri_2; + + return Py_BuildValue("(if)", best_j, factor); +} + +/* +** findfactor finds a factor f so that the energy in A-fB is minimal. +** See the comment for findfit for details. +*/ +static PyObject * +audioop_findfactor(PyObject *self, PyObject *args) +{ + short *cp1, *cp2; + int len1, len2; + double sum_ri_2, sum_aij_ri, result; + + if ( !PyArg_ParseTuple(args, "s#s#:findfactor", + (char**)&cp1, &len1, (char**)&cp2, &len2) ) + return 0; + if ( len1 & 1 || len2 & 1 ) { + PyErr_SetString(AudioopError, "Strings should be even-sized"); + return 0; + } + if ( len1 != len2 ) { + PyErr_SetString(AudioopError, "Samples should be same size"); + return 0; + } + len2 >>= 1; + sum_ri_2 = _sum2(cp2, cp2, len2); + sum_aij_ri = _sum2(cp1, cp2, len2); + + result = sum_aij_ri / sum_ri_2; + + return PyFloat_FromDouble(result); +} + +/* +** findmax returns the index of the n-sized segment of the input sample +** that contains the most energy. +*/ +static PyObject * +audioop_findmax(PyObject *self, PyObject *args) +{ + short *cp1; + int len1, len2; + int j, best_j; + double aj_m1, aj_lm1; + double result, best_result; + + if ( !PyArg_ParseTuple(args, "s#i:findmax", + (char**)&cp1, &len1, &len2) ) + return 0; + if ( len1 & 1 ) { + PyErr_SetString(AudioopError, "Strings should be even-sized"); + return 0; + } + len1 >>= 1; + + if ( len2 < 0 || len1 < len2 ) { + PyErr_SetString(AudioopError, "Input sample should be longer"); + return 0; + } + + result = _sum2(cp1, cp1, len2); + + best_result = result; + 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 PyInt_FromLong(best_j); +} + +static PyObject * +audioop_avgpp(PyObject *self, PyObject *args) +{ + signed char *cp; + int len, size, val = 0, prevval = 0, prevextremevalid = 0, + prevextreme = 0; + int i; + double avg = 0.0; + int diff, prevdiff, extremediff, nextreme = 0; + + if ( !PyArg_ParseTuple(args, "s#i:avgpp", &cp, &len, &size) ) + return 0; + if ( size != 1 && size != 2 && size != 4 ) { + PyErr_SetString(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 max ) + max = extremediff; + } + prevextremevalid = 1; + prevextreme = prevval; + } + prevval = val; + if ( diff != 0 ) + prevdiff = diff; + } + return PyInt_FromLong(max); +} + +static PyObject * +audioop_cross(PyObject *self, PyObject *args) +{ + signed char *cp; + int len, size, val = 0; + int i; + int prevval, ncross; + + if ( !PyArg_ParseTuple(args, "s#i:cross", &cp, &len, &size) ) + return 0; + if ( size != 1 && size != 2 && size != 4 ) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + ncross = -1; + prevval = 17; /* Anything <> 0,1 */ + for ( i=0; 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 PyInt_FromLong(ncross); +} + +static PyObject * +audioop_mul(PyObject *self, PyObject *args) +{ + signed char *cp, *ncp; + int len, size, val = 0; + double factor, fval, maxval; + PyObject *rv; + int i; + + if ( !PyArg_ParseTuple(args, "s#id:mul", &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 { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + rv = PyString_FromStringAndSize(NULL, len); + if ( rv == 0 ) + return 0; + ncp = (signed char *)PyString_AsString(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) = (Py_Int32)val; + } + return rv; +} + +static PyObject * +audioop_tomono(PyObject *self, PyObject *args) +{ + signed char *cp, *ncp; + int len, size, val1 = 0, val2 = 0; + double fac1, fac2, fval, maxval; + PyObject *rv; + int i; + + if ( !PyArg_ParseTuple(args, "s#idd:tomono", + &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 { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + rv = PyString_FromStringAndSize(NULL, len/2); + if ( rv == 0 ) + return 0; + ncp = (signed char *)PyString_AsString(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)= (Py_Int32)val1; + } + return rv; +} + +static PyObject * +audioop_tostereo(PyObject *self, PyObject *args) +{ + signed char *cp, *ncp; + int len, new_len, size, val1, val2, val = 0; + double fac1, fac2, fval, maxval; + PyObject *rv; + int i; + + if ( !PyArg_ParseTuple(args, "s#idd:tostereo", + &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 { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + new_len = len*2; + if (new_len < 0) { + PyErr_SetString(PyExc_MemoryError, + "not enough memory for output buffer"); + return 0; + } + + rv = PyString_FromStringAndSize(NULL, new_len); + if ( rv == 0 ) + return 0; + ncp = (signed char *)PyString_AsString(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) = (Py_Int32)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) = (Py_Int32)val2; + } + return rv; +} + +static PyObject * +audioop_add(PyObject *self, PyObject *args) +{ + signed char *cp1, *cp2, *ncp; + int len1, len2, size, val1 = 0, val2 = 0, maxval, newval; + PyObject *rv; + int i; + + if ( !PyArg_ParseTuple(args, "s#s#i:add", + &cp1, &len1, &cp2, &len2, &size ) ) + return 0; + + if ( len1 != len2 ) { + PyErr_SetString(AudioopError, "Lengths should be the same"); + return 0; + } + + if ( size == 1 ) maxval = 0x7f; + else if ( size == 2 ) maxval = 0x7fff; + else if ( size == 4 ) maxval = 0x7fffffff; + else { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + rv = PyString_FromStringAndSize(NULL, len1); + if ( rv == 0 ) + return 0; + ncp = (signed char *)PyString_AsString(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); + + newval = val1 + val2; + /* truncate in case of overflow */ + if (newval > maxval) newval = maxval; + else if (newval < -maxval) newval = -maxval; + else if (size == 4 && (newval^val1) < 0 && (newval^val2) < 0) + newval = val1 > 0 ? maxval : - maxval; + + if ( size == 1 ) *CHARP(ncp, i) = (signed char)newval; + else if ( size == 2 ) *SHORTP(ncp, i) = (short)newval; + else if ( size == 4 ) *LONGP(ncp, i) = (Py_Int32)newval; + } + return rv; +} + +static PyObject * +audioop_bias(PyObject *self, PyObject *args) +{ + signed char *cp, *ncp; + int len, size, val = 0; + PyObject *rv; + int i; + int bias; + + if ( !PyArg_ParseTuple(args, "s#ii:bias", + &cp, &len, &size , &bias) ) + return 0; + + if ( size != 1 && size != 2 && size != 4) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + rv = PyString_FromStringAndSize(NULL, len); + if ( rv == 0 ) + return 0; + ncp = (signed char *)PyString_AsString(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) = (Py_Int32)(val+bias); + } + return rv; +} + +static PyObject * +audioop_reverse(PyObject *self, PyObject *args) +{ + signed char *cp; + unsigned char *ncp; + int len, size, val = 0; + PyObject *rv; + int i, j; + + if ( !PyArg_ParseTuple(args, "s#i:reverse", + &cp, &len, &size) ) + return 0; + + if ( size != 1 && size != 2 && size != 4 ) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + rv = PyString_FromStringAndSize(NULL, len); + if ( rv == 0 ) + return 0; + ncp = (unsigned char *)PyString_AsString(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) = (Py_Int32)(val<<16); + } + return rv; +} + +static PyObject * +audioop_lin2lin(PyObject *self, PyObject *args) +{ + signed char *cp; + unsigned char *ncp; + int len, new_len, size, size2, val = 0; + PyObject *rv; + int i, j; + + if ( !PyArg_ParseTuple(args, "s#ii:lin2lin", + &cp, &len, &size, &size2) ) + return 0; + + if ( (size != 1 && size != 2 && size != 4) || + (size2 != 1 && size2 != 2 && size2 != 4)) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + new_len = (len/size)*size2; + if (new_len < 0) { + PyErr_SetString(PyExc_MemoryError, + "not enough memory for output buffer"); + return 0; + } + rv = PyString_FromStringAndSize(NULL, new_len); + if ( rv == 0 ) + return 0; + ncp = (unsigned char *)PyString_AsString(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) = (Py_Int32)(val<<16); + } + return rv; +} + +static int +gcd(int a, int b) +{ + while (b > 0) { + int tmp = a % b; + a = b; + b = tmp; + } + return a; +} + +static PyObject * +audioop_ratecv(PyObject *self, PyObject *args) +{ + char *cp, *ncp; + int len, size, nchannels, inrate, outrate, weightA, weightB; + int chan, d, *prev_i, *cur_i, cur_o; + PyObject *state, *samps, *str, *rv = NULL; + int bytes_per_frame; + size_t alloc_size; + + weightA = 1; + weightB = 0; + if (!PyArg_ParseTuple(args, "s#iiiiO|ii:ratecv", &cp, &len, &size, + &nchannels, &inrate, &outrate, &state, + &weightA, &weightB)) + return NULL; + if (size != 1 && size != 2 && size != 4) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return NULL; + } + if (nchannels < 1) { + PyErr_SetString(AudioopError, "# of channels should be >= 1"); + return NULL; + } + bytes_per_frame = size * nchannels; + if (bytes_per_frame / nchannels != size) { + /* This overflow test is rigorously correct because + both multiplicands are >= 1. Use the argument names + from the docs for the error msg. */ + PyErr_SetString(PyExc_OverflowError, + "width * nchannels too big for a C int"); + return NULL; + } + if (weightA < 1 || weightB < 0) { + PyErr_SetString(AudioopError, + "weightA should be >= 1, weightB should be >= 0"); + return NULL; + } + if (len % bytes_per_frame != 0) { + PyErr_SetString(AudioopError, "not a whole number of frames"); + return NULL; + } + if (inrate <= 0 || outrate <= 0) { + PyErr_SetString(AudioopError, "sampling rate not > 0"); + return NULL; + } + /* divide inrate and outrate by their greatest common divisor */ + d = gcd(inrate, outrate); + inrate /= d; + outrate /= d; + + alloc_size = sizeof(int) * (unsigned)nchannels; + if (alloc_size < nchannels) { + PyErr_SetString(PyExc_MemoryError, + "not enough memory for output buffer"); + return 0; + } + prev_i = (int *) malloc(alloc_size); + cur_i = (int *) malloc(alloc_size); + if (prev_i == NULL || cur_i == NULL) { + (void) PyErr_NoMemory(); + goto exit; + } + + len /= bytes_per_frame; /* # of frames */ + + if (state == Py_None) { + d = -outrate; + for (chan = 0; chan < nchannels; chan++) + prev_i[chan] = cur_i[chan] = 0; + } + else { + if (!PyArg_ParseTuple(state, + "iO!;audioop.ratecv: illegal state argument", + &d, &PyTuple_Type, &samps)) + goto exit; + if (PyTuple_Size(samps) != nchannels) { + PyErr_SetString(AudioopError, + "illegal state argument"); + goto exit; + } + for (chan = 0; chan < nchannels; chan++) { + if (!PyArg_ParseTuple(PyTuple_GetItem(samps, chan), + "ii:ratecv", &prev_i[chan], + &cur_i[chan])) + goto exit; + } + } + + /* str <- Space for the output buffer. */ + { + /* There are len input frames, so we need (mathematically) + ceiling(len*outrate/inrate) output frames, and each frame + requires bytes_per_frame bytes. Computing this + without spurious overflow is the challenge; we can + settle for a reasonable upper bound, though. */ + int ceiling; /* the number of output frames */ + int nbytes; /* the number of output bytes needed */ + int q = len / inrate; + /* Now len = q * inrate + r exactly (with r = len % inrate), + and this is less than q * inrate + inrate = (q+1)*inrate. + So a reasonable upper bound on len*outrate/inrate is + ((q+1)*inrate)*outrate/inrate = + (q+1)*outrate. + */ + ceiling = (q+1) * outrate; + nbytes = ceiling * bytes_per_frame; + /* See whether anything overflowed; if not, get the space. */ + if (q+1 < 0 || + ceiling / outrate != q+1 || + nbytes / bytes_per_frame != ceiling) + str = NULL; + else + str = PyString_FromStringAndSize(NULL, nbytes); + + if (str == NULL) { + PyErr_SetString(PyExc_MemoryError, + "not enough memory for output buffer"); + goto exit; + } + } + ncp = PyString_AsString(str); + + for (;;) { + while (d < 0) { + if (len == 0) { + samps = PyTuple_New(nchannels); + if (samps == NULL) + goto exit; + for (chan = 0; chan < nchannels; chan++) + PyTuple_SetItem(samps, chan, + Py_BuildValue("(ii)", + prev_i[chan], + cur_i[chan])); + if (PyErr_Occurred()) + goto exit; + /* We have checked before that the length + * of the string fits into int. */ + len = (int)(ncp - PyString_AsString(str)); + if (len == 0) { + /*don't want to resize to zero length*/ + rv = PyString_FromStringAndSize("", 0); + Py_DECREF(str); + str = rv; + } else if (_PyString_Resize(&str, len) < 0) + goto exit; + rv = Py_BuildValue("(O(iO))", str, d, samps); + Py_DECREF(samps); + Py_DECREF(str); + goto exit; /* return rv */ + } + for (chan = 0; chan < nchannels; chan++) { + prev_i[chan] = cur_i[chan]; + if (size == 1) + cur_i[chan] = ((int)*CHARP(cp, 0)) << 8; + else if (size == 2) + cur_i[chan] = (int)*SHORTP(cp, 0); + else if (size == 4) + cur_i[chan] = ((int)*LONGP(cp, 0)) >> 16; + cp += size; + /* implements a simple digital filter */ + cur_i[chan] = + (weightA * cur_i[chan] + + weightB * prev_i[chan]) / + (weightA + weightB); + } + len--; + d += outrate; + } + while (d >= 0) { + for (chan = 0; chan < nchannels; chan++) { + cur_o = (prev_i[chan] * d + + cur_i[chan] * (outrate - d)) / + outrate; + if (size == 1) + *CHARP(ncp, 0) = (signed char)(cur_o >> 8); + else if (size == 2) + *SHORTP(ncp, 0) = (short)(cur_o); + else if (size == 4) + *LONGP(ncp, 0) = (Py_Int32)(cur_o<<16); + ncp += size; + } + d -= inrate; + } + } + exit: + if (prev_i != NULL) + free(prev_i); + if (cur_i != NULL) + free(cur_i); + return rv; +} + +static PyObject * +audioop_lin2ulaw(PyObject *self, PyObject *args) +{ + signed char *cp; + unsigned char *ncp; + int len, size, val = 0; + PyObject *rv; + int i; + + if ( !PyArg_ParseTuple(args, "s#i:lin2ulaw", + &cp, &len, &size) ) + return 0 ; + + if ( size != 1 && size != 2 && size != 4) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + rv = PyString_FromStringAndSize(NULL, len/size); + if ( rv == 0 ) + return 0; + ncp = (unsigned char *)PyString_AsString(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_14linear2ulaw(val); + } + return rv; +} + +static PyObject * +audioop_ulaw2lin(PyObject *self, PyObject *args) +{ + unsigned char *cp; + unsigned char cval; + signed char *ncp; + int len, new_len, size, val; + PyObject *rv; + int i; + + if ( !PyArg_ParseTuple(args, "s#i:ulaw2lin", + &cp, &len, &size) ) + return 0; + + if ( size != 1 && size != 2 && size != 4) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + new_len = len*size; + if (new_len < 0) { + PyErr_SetString(PyExc_MemoryError, + "not enough memory for output buffer"); + return 0; + } + rv = PyString_FromStringAndSize(NULL, new_len); + if ( rv == 0 ) + return 0; + ncp = (signed char *)PyString_AsString(rv); + + for ( i=0; i < new_len; i += size ) { + cval = *cp++; + val = st_ulaw2linear16(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) = (Py_Int32)(val<<16); + } + return rv; +} + +static PyObject * +audioop_lin2alaw(PyObject *self, PyObject *args) +{ + signed char *cp; + unsigned char *ncp; + int len, size, val = 0; + PyObject *rv; + int i; + + if ( !PyArg_ParseTuple(args, "s#i:lin2alaw", + &cp, &len, &size) ) + return 0; + + if ( size != 1 && size != 2 && size != 4) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + rv = PyString_FromStringAndSize(NULL, len/size); + if ( rv == 0 ) + return 0; + ncp = (unsigned char *)PyString_AsString(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_linear2alaw(val); + } + return rv; +} + +static PyObject * +audioop_alaw2lin(PyObject *self, PyObject *args) +{ + unsigned char *cp; + unsigned char cval; + signed char *ncp; + int len, new_len, size, val; + PyObject *rv; + int i; + + if ( !PyArg_ParseTuple(args, "s#i:alaw2lin", + &cp, &len, &size) ) + return 0; + + if ( size != 1 && size != 2 && size != 4) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + new_len = len*size; + if (new_len < 0) { + PyErr_SetString(PyExc_MemoryError, + "not enough memory for output buffer"); + return 0; + } + rv = PyString_FromStringAndSize(NULL, new_len); + if ( rv == 0 ) + return 0; + ncp = (signed char *)PyString_AsString(rv); + + for ( i=0; i < new_len; i += size ) { + cval = *cp++; + val = st_alaw2linear16(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) = (Py_Int32)(val<<16); + } + return rv; +} + +static PyObject * +audioop_lin2adpcm(PyObject *self, PyObject *args) +{ + signed char *cp; + signed char *ncp; + int len, size, val = 0, step, valpred, delta, + index, sign, vpdiff, diff; + PyObject *rv, *state, *str; + int i, outputbuffer = 0, bufferstep; + + if ( !PyArg_ParseTuple(args, "s#iO:lin2adpcm", + &cp, &len, &size, &state) ) + return 0; + + + if ( size != 1 && size != 2 && size != 4) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + str = PyString_FromStringAndSize(NULL, len/(size*2)); + if ( str == 0 ) + return 0; + ncp = (signed char *)PyString_AsString(str); + + /* Decode state, should have (value, step) */ + if ( state == Py_None ) { + /* First time, it seems. Set defaults */ + valpred = 0; + step = 7; + index = 0; + } else if ( !PyArg_ParseTuple(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 = Py_BuildValue("(O(ii))", str, valpred, index); + Py_DECREF(str); + return rv; +} + +static PyObject * +audioop_adpcm2lin(PyObject *self, PyObject *args) +{ + signed char *cp; + signed char *ncp; + int len, new_len, size, valpred, step, delta, index, sign, vpdiff; + PyObject *rv, *str, *state; + int i, inputbuffer = 0, bufferstep; + + if ( !PyArg_ParseTuple(args, "s#iO:adpcm2lin", + &cp, &len, &size, &state) ) + return 0; + + if ( size != 1 && size != 2 && size != 4) { + PyErr_SetString(AudioopError, "Size should be 1, 2 or 4"); + return 0; + } + + /* Decode state, should have (value, step) */ + if ( state == Py_None ) { + /* First time, it seems. Set defaults */ + valpred = 0; + step = 7; + index = 0; + } else if ( !PyArg_ParseTuple(state, "ii", &valpred, &index) ) + return 0; + + new_len = len*size*2; + if (new_len < 0) { + PyErr_SetString(PyExc_MemoryError, + "not enough memory for output buffer"); + return 0; + } + str = PyString_FromStringAndSize(NULL, new_len); + if ( str == 0 ) + return 0; + ncp = (signed char *)PyString_AsString(str); + + step = stepsizeTable[index]; + bufferstep = 0; + + for ( i=0; i < new_len; 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) = (Py_Int32)(valpred<<16); + } + + rv = Py_BuildValue("(O(ii))", str, valpred, index); + Py_DECREF(str); + return rv; +} + +static PyMethodDef audioop_methods[] = { + { "max", audioop_max, METH_VARARGS }, + { "minmax", audioop_minmax, METH_VARARGS }, + { "avg", audioop_avg, METH_VARARGS }, + { "maxpp", audioop_maxpp, METH_VARARGS }, + { "avgpp", audioop_avgpp, METH_VARARGS }, + { "rms", audioop_rms, METH_VARARGS }, + { "findfit", audioop_findfit, METH_VARARGS }, + { "findmax", audioop_findmax, METH_VARARGS }, + { "findfactor", audioop_findfactor, METH_VARARGS }, + { "cross", audioop_cross, METH_VARARGS }, + { "mul", audioop_mul, METH_VARARGS }, + { "add", audioop_add, METH_VARARGS }, + { "bias", audioop_bias, METH_VARARGS }, + { "ulaw2lin", audioop_ulaw2lin, METH_VARARGS }, + { "lin2ulaw", audioop_lin2ulaw, METH_VARARGS }, + { "alaw2lin", audioop_alaw2lin, METH_VARARGS }, + { "lin2alaw", audioop_lin2alaw, METH_VARARGS }, + { "lin2lin", audioop_lin2lin, METH_VARARGS }, + { "adpcm2lin", audioop_adpcm2lin, METH_VARARGS }, + { "lin2adpcm", audioop_lin2adpcm, METH_VARARGS }, + { "tomono", audioop_tomono, METH_VARARGS }, + { "tostereo", audioop_tostereo, METH_VARARGS }, + { "getsample", audioop_getsample, METH_VARARGS }, + { "reverse", audioop_reverse, METH_VARARGS }, + { "ratecv", audioop_ratecv, METH_VARARGS }, + { 0, 0 } +}; + +PyMODINIT_FUNC +initaudioop(void) +{ + PyObject *m, *d; + m = Py_InitModule("audioop", audioop_methods); + if (m == NULL) + return; + d = PyModule_GetDict(m); + if (d == NULL) + return; + AudioopError = PyErr_NewException("audioop.error", NULL, NULL); + if (AudioopError != NULL) + PyDict_SetItemString(d,"error",AudioopError); +}