1646 lines
51 KiB
C
1646 lines
51 KiB
C
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/* audioopmodule - Module to detect peak values in arrays */
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#include "Python.h"
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#if SIZEOF_INT == 4
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typedef int Py_Int32;
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typedef unsigned int Py_UInt32;
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#else
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#if SIZEOF_LONG == 4
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typedef long Py_Int32;
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typedef unsigned long Py_UInt32;
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#else
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#error "No 4-byte integral type"
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#endif
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#endif
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typedef short PyInt16;
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#if defined(__CHAR_UNSIGNED__)
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#if defined(signed)
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/* This module currently does not work on systems where only unsigned
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characters are available. Take it out of Setup. Sorry. */
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#endif
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#endif
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static const int maxvals[] = {0, 0x7F, 0x7FFF, 0x7FFFFF, 0x7FFFFFFF};
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static const int minvals[] = {0, -0x80, -0x8000, -0x800000, -0x80000000};
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static const unsigned int masks[] = {0, 0xFF, 0xFFFF, 0xFFFFFF, 0xFFFFFFFF};
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static int
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fbound(double val, double minval, double maxval)
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{
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if (val > maxval)
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val = maxval;
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else if (val < minval + 1)
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val = minval;
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return val;
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}
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/* Code shamelessly stolen from sox, 12.17.7, g711.c
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** (c) Craig Reese, Joe Campbell and Jeff Poskanzer 1989 */
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/* From g711.c:
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*
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* December 30, 1994:
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* Functions linear2alaw, linear2ulaw have been updated to correctly
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* convert unquantized 16 bit values.
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* Tables for direct u- to A-law and A- to u-law conversions have been
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* corrected.
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* Borge Lindberg, Center for PersonKommunikation, Aalborg University.
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* bli@cpk.auc.dk
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*
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*/
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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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#define SIGN_BIT (0x80) /* Sign bit for a A-law byte. */
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#define QUANT_MASK (0xf) /* Quantization field mask. */
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#define SEG_SHIFT (4) /* Left shift for segment number. */
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#define SEG_MASK (0x70) /* Segment field mask. */
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static PyInt16 seg_aend[8] = {0x1F, 0x3F, 0x7F, 0xFF,
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0x1FF, 0x3FF, 0x7FF, 0xFFF};
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static PyInt16 seg_uend[8] = {0x3F, 0x7F, 0xFF, 0x1FF,
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0x3FF, 0x7FF, 0xFFF, 0x1FFF};
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static PyInt16
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search(PyInt16 val, PyInt16 *table, int size)
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{
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int i;
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for (i = 0; i < size; i++) {
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if (val <= *table++)
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return (i);
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}
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return (size);
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}
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#define st_ulaw2linear16(uc) (_st_ulaw2linear16[uc])
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#define st_alaw2linear16(uc) (_st_alaw2linear16[uc])
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static PyInt16 _st_ulaw2linear16[256] = {
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-32124, -31100, -30076, -29052, -28028, -27004, -25980,
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-24956, -23932, -22908, -21884, -20860, -19836, -18812,
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-17788, -16764, -15996, -15484, -14972, -14460, -13948,
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-13436, -12924, -12412, -11900, -11388, -10876, -10364,
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-9852, -9340, -8828, -8316, -7932, -7676, -7420,
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-7164, -6908, -6652, -6396, -6140, -5884, -5628,
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-5372, -5116, -4860, -4604, -4348, -4092, -3900,
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-3772, -3644, -3516, -3388, -3260, -3132, -3004,
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-2876, -2748, -2620, -2492, -2364, -2236, -2108,
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-1980, -1884, -1820, -1756, -1692, -1628, -1564,
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-1500, -1436, -1372, -1308, -1244, -1180, -1116,
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-1052, -988, -924, -876, -844, -812, -780,
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-748, -716, -684, -652, -620, -588, -556,
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-524, -492, -460, -428, -396, -372, -356,
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-340, -324, -308, -292, -276, -260, -244,
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-228, -212, -196, -180, -164, -148, -132,
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-120, -112, -104, -96, -88, -80, -72,
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-64, -56, -48, -40, -32, -24, -16,
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-8, 0, 32124, 31100, 30076, 29052, 28028,
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27004, 25980, 24956, 23932, 22908, 21884, 20860,
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19836, 18812, 17788, 16764, 15996, 15484, 14972,
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14460, 13948, 13436, 12924, 12412, 11900, 11388,
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10876, 10364, 9852, 9340, 8828, 8316, 7932,
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7676, 7420, 7164, 6908, 6652, 6396, 6140,
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5884, 5628, 5372, 5116, 4860, 4604, 4348,
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4092, 3900, 3772, 3644, 3516, 3388, 3260,
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3132, 3004, 2876, 2748, 2620, 2492, 2364,
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2236, 2108, 1980, 1884, 1820, 1756, 1692,
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1628, 1564, 1500, 1436, 1372, 1308, 1244,
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1180, 1116, 1052, 988, 924, 876, 844,
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812, 780, 748, 716, 684, 652, 620,
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588, 556, 524, 492, 460, 428, 396,
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372, 356, 340, 324, 308, 292, 276,
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260, 244, 228, 212, 196, 180, 164,
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148, 132, 120, 112, 104, 96, 88,
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80, 72, 64, 56, 48, 40, 32,
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24, 16, 8, 0
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};
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/*
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* linear2ulaw() accepts a 14-bit signed integer and encodes it as u-law data
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* stored in a unsigned char. This function should only be called with
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* the data shifted such that it only contains information in the lower
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* 14-bits.
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*
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* In order to simplify the encoding process, the original linear magnitude
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* is biased by adding 33 which shifts the encoding range from (0 - 8158) to
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* (33 - 8191). The result can be seen in the following encoding table:
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*
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* Biased Linear Input Code Compressed Code
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* ------------------------ ---------------
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* 00000001wxyza 000wxyz
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* 0000001wxyzab 001wxyz
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* 000001wxyzabc 010wxyz
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* 00001wxyzabcd 011wxyz
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* 0001wxyzabcde 100wxyz
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* 001wxyzabcdef 101wxyz
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* 01wxyzabcdefg 110wxyz
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* 1wxyzabcdefgh 111wxyz
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*
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* Each biased linear code has a leading 1 which identifies the segment
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* number. The value of the segment number is equal to 7 minus the number
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* of leading 0's. The quantization interval is directly available as the
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* four bits wxyz. * The trailing bits (a - h) are ignored.
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*
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* Ordinarily the complement of the resulting code word is used for
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* transmission, and so the code word is complemented before it is returned.
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*
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* For further information see John C. Bellamy's Digital Telephony, 1982,
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* John Wiley & Sons, pps 98-111 and 472-476.
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*/
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static unsigned char
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st_14linear2ulaw(PyInt16 pcm_val) /* 2's complement (14-bit range) */
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{
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PyInt16 mask;
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PyInt16 seg;
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unsigned char uval;
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/* The original sox code does this in the calling function, not here */
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pcm_val = pcm_val >> 2;
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/* u-law inverts all bits */
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/* Get the sign and the magnitude of the value. */
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if (pcm_val < 0) {
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pcm_val = -pcm_val;
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mask = 0x7F;
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} else {
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mask = 0xFF;
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}
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if ( pcm_val > CLIP ) pcm_val = CLIP; /* clip the magnitude */
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pcm_val += (BIAS >> 2);
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/* Convert the scaled magnitude to segment number. */
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seg = search(pcm_val, seg_uend, 8);
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/*
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* Combine the sign, segment, quantization bits;
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* and complement the code word.
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*/
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if (seg >= 8) /* out of range, return maximum value. */
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return (unsigned char) (0x7F ^ mask);
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else {
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uval = (unsigned char) (seg << 4) | ((pcm_val >> (seg + 1)) & 0xF);
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return (uval ^ mask);
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}
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}
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static PyInt16 _st_alaw2linear16[256] = {
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-5504, -5248, -6016, -5760, -4480, -4224, -4992,
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-4736, -7552, -7296, -8064, -7808, -6528, -6272,
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-7040, -6784, -2752, -2624, -3008, -2880, -2240,
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-2112, -2496, -2368, -3776, -3648, -4032, -3904,
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-3264, -3136, -3520, -3392, -22016, -20992, -24064,
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-23040, -17920, -16896, -19968, -18944, -30208, -29184,
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-32256, -31232, -26112, -25088, -28160, -27136, -11008,
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-10496, -12032, -11520, -8960, -8448, -9984, -9472,
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-15104, -14592, -16128, -15616, -13056, -12544, -14080,
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-13568, -344, -328, -376, -360, -280, -264,
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-312, -296, -472, -456, -504, -488, -408,
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-392, -440, -424, -88, -72, -120, -104,
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-24, -8, -56, -40, -216, -200, -248,
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-232, -152, -136, -184, -168, -1376, -1312,
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-1504, -1440, -1120, -1056, -1248, -1184, -1888,
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-1824, -2016, -1952, -1632, -1568, -1760, -1696,
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-688, -656, -752, -720, -560, -528, -624,
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-592, -944, -912, -1008, -976, -816, -784,
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-880, -848, 5504, 5248, 6016, 5760, 4480,
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4224, 4992, 4736, 7552, 7296, 8064, 7808,
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6528, 6272, 7040, 6784, 2752, 2624, 3008,
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2880, 2240, 2112, 2496, 2368, 3776, 3648,
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4032, 3904, 3264, 3136, 3520, 3392, 22016,
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20992, 24064, 23040, 17920, 16896, 19968, 18944,
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30208, 29184, 32256, 31232, 26112, 25088, 28160,
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27136, 11008, 10496, 12032, 11520, 8960, 8448,
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9984, 9472, 15104, 14592, 16128, 15616, 13056,
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12544, 14080, 13568, 344, 328, 376, 360,
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280, 264, 312, 296, 472, 456, 504,
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488, 408, 392, 440, 424, 88, 72,
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120, 104, 24, 8, 56, 40, 216,
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200, 248, 232, 152, 136, 184, 168,
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1376, 1312, 1504, 1440, 1120, 1056, 1248,
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1184, 1888, 1824, 2016, 1952, 1632, 1568,
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1760, 1696, 688, 656, 752, 720, 560,
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528, 624, 592, 944, 912, 1008, 976,
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816, 784, 880, 848
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};
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/*
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* linear2alaw() accepts an 13-bit signed integer and encodes it as A-law data
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* stored in a unsigned char. This function should only be called with
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* the data shifted such that it only contains information in the lower
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* 13-bits.
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*
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* Linear Input Code Compressed Code
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* ------------------------ ---------------
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* 0000000wxyza 000wxyz
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* 0000001wxyza 001wxyz
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* 000001wxyzab 010wxyz
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* 00001wxyzabc 011wxyz
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* 0001wxyzabcd 100wxyz
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* 001wxyzabcde 101wxyz
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* 01wxyzabcdef 110wxyz
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* 1wxyzabcdefg 111wxyz
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*
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* For further information see John C. Bellamy's Digital Telephony, 1982,
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* John Wiley & Sons, pps 98-111 and 472-476.
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*/
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static unsigned char
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st_linear2alaw(PyInt16 pcm_val) /* 2's complement (13-bit range) */
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{
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PyInt16 mask;
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short seg;
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unsigned char aval;
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/* The original sox code does this in the calling function, not here */
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pcm_val = pcm_val >> 3;
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/* A-law using even bit inversion */
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if (pcm_val >= 0) {
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mask = 0xD5; /* sign (7th) bit = 1 */
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} else {
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mask = 0x55; /* sign bit = 0 */
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pcm_val = -pcm_val - 1;
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}
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/* Convert the scaled magnitude to segment number. */
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seg = search(pcm_val, seg_aend, 8);
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/* Combine the sign, segment, and quantization bits. */
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if (seg >= 8) /* out of range, return maximum value. */
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return (unsigned char) (0x7F ^ mask);
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else {
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aval = (unsigned char) seg << SEG_SHIFT;
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if (seg < 2)
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aval |= (pcm_val >> 1) & QUANT_MASK;
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else
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aval |= (pcm_val >> seg) & QUANT_MASK;
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return (aval ^ mask);
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}
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}
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/* End of code taken from sox */
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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) ((Py_Int32 *)(cp+i))
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static PyObject *AudioopError;
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static int
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audioop_check_size(int size)
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||
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{
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if (size != 1 && size != 2 && size != 4) {
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PyErr_SetString(AudioopError, "Size should be 1, 2 or 4");
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return 0;
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}
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else
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return 1;
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}
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||
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||
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static int
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audioop_check_parameters(int len, int size)
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{
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if (!audioop_check_size(size))
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return 0;
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if (len % size != 0) {
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PyErr_SetString(AudioopError, "not a whole number of frames");
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return 0;
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}
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return 1;
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}
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static PyObject *
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audioop_getsample(PyObject *self, PyObject *args)
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||
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{
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signed char *cp;
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int len, size, val = 0;
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int i;
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if ( !PyArg_ParseTuple(args, "s#ii:getsample", &cp, &len, &size, &i) )
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return 0;
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if (!audioop_check_parameters(len, size))
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return NULL;
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if ( i < 0 || i >= len/size ) {
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PyErr_SetString(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 PyInt_FromLong(val);
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||
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}
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||
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static PyObject *
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||
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audioop_max(PyObject *self, PyObject *args)
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||
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{
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||
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signed char *cp;
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||
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int len, size, val = 0;
|
||
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int i;
|
||
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unsigned int absval, max = 0;
|
||
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||
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if ( !PyArg_ParseTuple(args, "s#i:max", &cp, &len, &size) )
|
||
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return 0;
|
||
|
if (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
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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) absval = (-val);
|
||
|
else absval = val;
|
||
|
if (absval > max) max = absval;
|
||
|
}
|
||
|
if (max <= INT_MAX)
|
||
|
return PyInt_FromLong(max);
|
||
|
else
|
||
|
return PyLong_FromUnsignedLong(max);
|
||
|
}
|
||
|
|
||
|
static PyObject *
|
||
|
audioop_minmax(PyObject *self, PyObject *args)
|
||
|
{
|
||
|
signed char *cp;
|
||
|
int len, size, val = 0;
|
||
|
int i;
|
||
|
int min = 0x7fffffff, max = -0x80000000;
|
||
|
|
||
|
if (!PyArg_ParseTuple(args, "s#i:minmax", &cp, &len, &size))
|
||
|
return NULL;
|
||
|
if (!audioop_check_parameters(len, size))
|
||
|
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 (!audioop_check_parameters(len, size))
|
||
|
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);
|
||
|
avg += val;
|
||
|
}
|
||
|
if ( len == 0 )
|
||
|
val = 0;
|
||
|
else
|
||
|
val = (int)floor(avg / (double)(len/size));
|
||
|
return PyInt_FromLong(val);
|
||
|
}
|
||
|
|
||
|
static PyObject *
|
||
|
audioop_rms(PyObject *self, PyObject *args)
|
||
|
{
|
||
|
signed char *cp;
|
||
|
int len, size, val = 0;
|
||
|
int i;
|
||
|
unsigned int res;
|
||
|
double sum_squares = 0.0;
|
||
|
|
||
|
if ( !PyArg_ParseTuple(args, "s#i:rms", &cp, &len, &size) )
|
||
|
return 0;
|
||
|
if (!audioop_check_parameters(len, size))
|
||
|
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);
|
||
|
sum_squares += (double)val*(double)val;
|
||
|
}
|
||
|
if ( len == 0 )
|
||
|
res = 0;
|
||
|
else
|
||
|
res = (unsigned int)sqrt(sum_squares / (double)(len/size));
|
||
|
if (res <= INT_MAX)
|
||
|
return PyInt_FromLong(res);
|
||
|
else
|
||
|
return PyLong_FromUnsignedLong(res);
|
||
|
}
|
||
|
|
||
|
static double _sum2(short *a, short *b, int len)
|
||
|
{
|
||
|
int i;
|
||
|
double sum = 0.0;
|
||
|
|
||
|
for( i=0; i<len; i++) {
|
||
|
sum = sum + (double)a[i]*(double)b[i];
|
||
|
}
|
||
|
return sum;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
** Findfit tries to locate a sample within another sample. Its main use
|
||
|
** is in echo-cancellation (to find the feedback of the output signal in
|
||
|
** the input signal).
|
||
|
** The method used is as follows:
|
||
|
**
|
||
|
** let R be the reference signal (length n) and A the input signal (length N)
|
||
|
** with N > 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;
|
||
|
|
||
|
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;
|
||
|
|
||
|
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 sum = 0.0;
|
||
|
unsigned int avg;
|
||
|
int diff, prevdiff, nextreme = 0;
|
||
|
|
||
|
if ( !PyArg_ParseTuple(args, "s#i:avgpp", &cp, &len, &size) )
|
||
|
return 0;
|
||
|
if (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
if (len <= size*2)
|
||
|
return PyInt_FromLong(0);
|
||
|
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);
|
||
|
prevdiff = 17; /* Anything != 0, 1 */
|
||
|
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);
|
||
|
if (val != prevval) {
|
||
|
diff = val < prevval;
|
||
|
if (prevdiff == !diff) {
|
||
|
/* Derivative changed sign. Compute difference to last
|
||
|
** extreme value and remember.
|
||
|
*/
|
||
|
if (prevextremevalid) {
|
||
|
sum += fabs((double)prevval - (double)prevextreme);
|
||
|
nextreme++;
|
||
|
}
|
||
|
prevextremevalid = 1;
|
||
|
prevextreme = prevval;
|
||
|
}
|
||
|
prevval = val;
|
||
|
prevdiff = diff;
|
||
|
}
|
||
|
}
|
||
|
if ( nextreme == 0 )
|
||
|
avg = 0;
|
||
|
else
|
||
|
avg = (unsigned int)(sum / (double)nextreme);
|
||
|
if (avg <= INT_MAX)
|
||
|
return PyInt_FromLong(avg);
|
||
|
else
|
||
|
return PyLong_FromUnsignedLong(avg);
|
||
|
}
|
||
|
|
||
|
static PyObject *
|
||
|
audioop_maxpp(PyObject *self, PyObject *args)
|
||
|
{
|
||
|
signed char *cp;
|
||
|
int len, size, val = 0, prevval = 0, prevextremevalid = 0,
|
||
|
prevextreme = 0;
|
||
|
int i;
|
||
|
unsigned int max = 0, extremediff;
|
||
|
int diff, prevdiff;
|
||
|
|
||
|
if ( !PyArg_ParseTuple(args, "s#i:maxpp", &cp, &len, &size) )
|
||
|
return 0;
|
||
|
if (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
if (len <= size)
|
||
|
return PyInt_FromLong(0);
|
||
|
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);
|
||
|
prevdiff = 17; /* Anything != 0, 1 */
|
||
|
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);
|
||
|
if (val != prevval) {
|
||
|
diff = val < prevval;
|
||
|
if (prevdiff == !diff) {
|
||
|
/* Derivative changed sign. Compute difference to
|
||
|
** last extreme value and remember.
|
||
|
*/
|
||
|
if (prevextremevalid) {
|
||
|
if (prevval < prevextreme)
|
||
|
extremediff = (unsigned int)prevextreme -
|
||
|
(unsigned int)prevval;
|
||
|
else
|
||
|
extremediff = (unsigned int)prevval -
|
||
|
(unsigned int)prevextreme;
|
||
|
if ( extremediff > max )
|
||
|
max = extremediff;
|
||
|
}
|
||
|
prevextremevalid = 1;
|
||
|
prevextreme = prevval;
|
||
|
}
|
||
|
prevval = val;
|
||
|
prevdiff = diff;
|
||
|
}
|
||
|
}
|
||
|
if (max <= INT_MAX)
|
||
|
return PyInt_FromLong(max);
|
||
|
else
|
||
|
return PyLong_FromUnsignedLong(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 (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
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 PyInt_FromLong(ncross);
|
||
|
}
|
||
|
|
||
|
static PyObject *
|
||
|
audioop_mul(PyObject *self, PyObject *args)
|
||
|
{
|
||
|
signed char *cp, *ncp;
|
||
|
int len, size, val = 0;
|
||
|
double factor, fval, maxval, minval;
|
||
|
PyObject *rv;
|
||
|
int i;
|
||
|
|
||
|
if ( !PyArg_ParseTuple(args, "s#id:mul", &cp, &len, &size, &factor ) )
|
||
|
return 0;
|
||
|
if (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
|
||
|
maxval = (double) maxvals[size];
|
||
|
minval = (double) minvals[size];
|
||
|
|
||
|
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;
|
||
|
val = (int)floor(fbound(fval, minval, maxval));
|
||
|
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, minval;
|
||
|
PyObject *rv;
|
||
|
int i;
|
||
|
|
||
|
if ( !PyArg_ParseTuple(args, "s#idd:tomono",
|
||
|
&cp, &len, &size, &fac1, &fac2 ) )
|
||
|
return 0;
|
||
|
if (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
if (((len / size) & 1) != 0) {
|
||
|
PyErr_SetString(AudioopError, "not a whole number of frames");
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
maxval = (double) maxvals[size];
|
||
|
minval = (double) minvals[size];
|
||
|
|
||
|
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;
|
||
|
val1 = (int)floor(fbound(fval, minval, maxval));
|
||
|
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, size, val1, val2, val = 0;
|
||
|
double fac1, fac2, fval, maxval, minval;
|
||
|
PyObject *rv;
|
||
|
int i;
|
||
|
|
||
|
if ( !PyArg_ParseTuple(args, "s#idd:tostereo",
|
||
|
&cp, &len, &size, &fac1, &fac2 ) )
|
||
|
return 0;
|
||
|
if (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
|
||
|
maxval = (double) maxvals[size];
|
||
|
minval = (double) minvals[size];
|
||
|
|
||
|
if (len > INT_MAX/2) {
|
||
|
PyErr_SetString(PyExc_MemoryError,
|
||
|
"not enough memory for output buffer");
|
||
|
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 ) {
|
||
|
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;
|
||
|
val1 = (int)floor(fbound(fval, minval, maxval));
|
||
|
|
||
|
fval = (double)val*fac2;
|
||
|
val2 = (int)floor(fbound(fval, minval, maxval));
|
||
|
|
||
|
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, minval, maxval, newval;
|
||
|
PyObject *rv;
|
||
|
int i;
|
||
|
|
||
|
if ( !PyArg_ParseTuple(args, "s#s#i:add",
|
||
|
&cp1, &len1, &cp2, &len2, &size ) )
|
||
|
return 0;
|
||
|
if (!audioop_check_parameters(len1, size))
|
||
|
return NULL;
|
||
|
if ( len1 != len2 ) {
|
||
|
PyErr_SetString(AudioopError, "Lengths should be the same");
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
maxval = maxvals[size];
|
||
|
minval = minvals[size];
|
||
|
|
||
|
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);
|
||
|
|
||
|
if (size < 4) {
|
||
|
newval = val1 + val2;
|
||
|
/* truncate in case of overflow */
|
||
|
if (newval > maxval)
|
||
|
newval = maxval;
|
||
|
else if (newval < minval)
|
||
|
newval = minval;
|
||
|
}
|
||
|
else {
|
||
|
double fval = (double)val1 + (double)val2;
|
||
|
/* truncate in case of overflow */
|
||
|
newval = (int)floor(fbound(fval, minval, 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;
|
||
|
unsigned int val = 0, mask;
|
||
|
PyObject *rv;
|
||
|
int i;
|
||
|
int bias;
|
||
|
|
||
|
if ( !PyArg_ParseTuple(args, "s#ii:bias",
|
||
|
&cp, &len, &size , &bias) )
|
||
|
return 0;
|
||
|
|
||
|
if (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
|
||
|
rv = PyString_FromStringAndSize(NULL, len);
|
||
|
if ( rv == 0 )
|
||
|
return 0;
|
||
|
ncp = (signed char *)PyString_AsString(rv);
|
||
|
|
||
|
mask = masks[size];
|
||
|
|
||
|
for ( i=0; i < len; i += size ) {
|
||
|
if ( size == 1 ) val = (unsigned int)(unsigned char)*CHARP(cp, i);
|
||
|
else if ( size == 2 ) val = (unsigned int)(unsigned short)*SHORTP(cp, i);
|
||
|
else if ( size == 4 ) val = (unsigned int)(Py_UInt32)*LONGP(cp, i);
|
||
|
|
||
|
val += (unsigned int)bias;
|
||
|
/* wrap around in case of overflow */
|
||
|
val &= mask;
|
||
|
|
||
|
if ( size == 1 ) *CHARP(ncp, i) = (signed char)(unsigned char)val;
|
||
|
else if ( size == 2 ) *SHORTP(ncp, i) = (short)(unsigned short)val;
|
||
|
else if ( size == 4 ) *LONGP(ncp, i) = (Py_Int32)(Py_UInt32)val;
|
||
|
}
|
||
|
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 (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
|
||
|
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)) << 24;
|
||
|
else if ( size == 2 ) val = ((int)*SHORTP(cp, i)) << 16;
|
||
|
else if ( size == 4 ) val = (int)*LONGP(cp, i);
|
||
|
|
||
|
j = len - i - size;
|
||
|
|
||
|
if ( size == 1 ) *CHARP(ncp, j) = (signed char)(val >> 24);
|
||
|
else if ( size == 2 ) *SHORTP(ncp, j) = (short)(val >> 16);
|
||
|
else if ( size == 4 ) *LONGP(ncp, j) = (Py_Int32)val;
|
||
|
}
|
||
|
return rv;
|
||
|
}
|
||
|
|
||
|
static PyObject *
|
||
|
audioop_lin2lin(PyObject *self, PyObject *args)
|
||
|
{
|
||
|
signed char *cp;
|
||
|
unsigned char *ncp;
|
||
|
int len, size, size2, val = 0;
|
||
|
PyObject *rv;
|
||
|
int i, j;
|
||
|
|
||
|
if ( !PyArg_ParseTuple(args, "s#ii:lin2lin",
|
||
|
&cp, &len, &size, &size2) )
|
||
|
return 0;
|
||
|
|
||
|
if (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
if (!audioop_check_size(size2))
|
||
|
return NULL;
|
||
|
|
||
|
if (len/size > INT_MAX/size2) {
|
||
|
PyErr_SetString(PyExc_MemoryError,
|
||
|
"not enough memory for output buffer");
|
||
|
return 0;
|
||
|
}
|
||
|
rv = PyString_FromStringAndSize(NULL, (len/size)*size2);
|
||
|
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)) << 24;
|
||
|
else if ( size == 2 ) val = ((int)*SHORTP(cp, i)) << 16;
|
||
|
else if ( size == 4 ) val = (int)*LONGP(cp, i);
|
||
|
|
||
|
if ( size2 == 1 ) *CHARP(ncp, j) = (signed char)(val >> 24);
|
||
|
else if ( size2 == 2 ) *SHORTP(ncp, j) = (short)(val >> 16);
|
||
|
else if ( size2 == 4 ) *LONGP(ncp, j) = (Py_Int32)val;
|
||
|
}
|
||
|
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;
|
||
|
|
||
|
weightA = 1;
|
||
|
weightB = 0;
|
||
|
if (!PyArg_ParseTuple(args, "s#iiiiO|ii:ratecv", &cp, &len, &size,
|
||
|
&nchannels, &inrate, &outrate, &state,
|
||
|
&weightA, &weightB))
|
||
|
return NULL;
|
||
|
if (!audioop_check_size(size))
|
||
|
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;
|
||
|
/* divide weightA and weightB by their greatest common divisor */
|
||
|
d = gcd(weightA, weightB);
|
||
|
weightA /= d;
|
||
|
weightA /= d;
|
||
|
|
||
|
if ((size_t)nchannels > PY_SIZE_MAX/sizeof(int)) {
|
||
|
PyErr_SetString(PyExc_MemoryError,
|
||
|
"not enough memory for output buffer");
|
||
|
return 0;
|
||
|
}
|
||
|
prev_i = (int *) malloc(nchannels * sizeof(int));
|
||
|
cur_i = (int *) malloc(nchannels * sizeof(int));
|
||
|
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. */
|
||
|
if (len == 0)
|
||
|
str = PyString_FromStringAndSize(NULL, 0);
|
||
|
else {
|
||
|
/* 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, in this
|
||
|
case ceiling(len/inrate) * outrate. */
|
||
|
|
||
|
/* compute ceiling(len/inrate) without overflow */
|
||
|
int q = len > 0 ? 1 + (len - 1) / inrate : 0;
|
||
|
if (outrate > INT_MAX / q / bytes_per_frame)
|
||
|
str = NULL;
|
||
|
else
|
||
|
str = PyString_FromStringAndSize(NULL,
|
||
|
q * outrate * bytes_per_frame);
|
||
|
}
|
||
|
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)) << 24;
|
||
|
else if (size == 2)
|
||
|
cur_i[chan] = ((int)*SHORTP(cp, 0)) << 16;
|
||
|
else if (size == 4)
|
||
|
cur_i[chan] = (int)*LONGP(cp, 0);
|
||
|
cp += size;
|
||
|
/* implements a simple digital filter */
|
||
|
cur_i[chan] = (int)(
|
||
|
((double)weightA * (double)cur_i[chan] +
|
||
|
(double)weightB * (double)prev_i[chan]) /
|
||
|
((double)weightA + (double)weightB));
|
||
|
}
|
||
|
len--;
|
||
|
d += outrate;
|
||
|
}
|
||
|
while (d >= 0) {
|
||
|
for (chan = 0; chan < nchannels; chan++) {
|
||
|
cur_o = (int)(((double)prev_i[chan] * (double)d +
|
||
|
(double)cur_i[chan] * (double)(outrate - d)) /
|
||
|
(double)outrate);
|
||
|
if (size == 1)
|
||
|
*CHARP(ncp, 0) = (signed char)(cur_o >> 24);
|
||
|
else if (size == 2)
|
||
|
*SHORTP(ncp, 0) = (short)(cur_o >> 16);
|
||
|
else if (size == 4)
|
||
|
*LONGP(ncp, 0) = (Py_Int32)(cur_o);
|
||
|
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 (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
|
||
|
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, size, val;
|
||
|
PyObject *rv;
|
||
|
int i;
|
||
|
|
||
|
if ( !PyArg_ParseTuple(args, "s#i:ulaw2lin",
|
||
|
&cp, &len, &size) )
|
||
|
return 0;
|
||
|
|
||
|
if (!audioop_check_size(size))
|
||
|
return NULL;
|
||
|
|
||
|
if (len > INT_MAX/size) {
|
||
|
PyErr_SetString(PyExc_MemoryError,
|
||
|
"not enough memory for output buffer");
|
||
|
return 0;
|
||
|
}
|
||
|
rv = PyString_FromStringAndSize(NULL, len*size);
|
||
|
if ( rv == 0 )
|
||
|
return 0;
|
||
|
ncp = (signed char *)PyString_AsString(rv);
|
||
|
|
||
|
for ( i=0; i < len*size; 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 (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
|
||
|
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, size, val;
|
||
|
PyObject *rv;
|
||
|
int i;
|
||
|
|
||
|
if ( !PyArg_ParseTuple(args, "s#i:alaw2lin",
|
||
|
&cp, &len, &size) )
|
||
|
return 0;
|
||
|
|
||
|
if (!audioop_check_size(size))
|
||
|
return NULL;
|
||
|
|
||
|
if (len > INT_MAX/size) {
|
||
|
PyErr_SetString(PyExc_MemoryError,
|
||
|
"not enough memory for output buffer");
|
||
|
return 0;
|
||
|
}
|
||
|
rv = PyString_FromStringAndSize(NULL, len*size);
|
||
|
if ( rv == 0 )
|
||
|
return 0;
|
||
|
ncp = (signed char *)PyString_AsString(rv);
|
||
|
|
||
|
for ( i=0; i < len*size; 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 (!audioop_check_parameters(len, size))
|
||
|
return NULL;
|
||
|
|
||
|
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;
|
||
|
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, 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 (!audioop_check_size(size))
|
||
|
return NULL;
|
||
|
|
||
|
/* Decode state, should have (value, step) */
|
||
|
if ( state == Py_None ) {
|
||
|
/* First time, it seems. Set defaults */
|
||
|
valpred = 0;
|
||
|
index = 0;
|
||
|
} else if ( !PyArg_ParseTuple(state, "ii", &valpred, &index) )
|
||
|
return 0;
|
||
|
|
||
|
if (len > (INT_MAX/2)/size) {
|
||
|
PyErr_SetString(PyExc_MemoryError,
|
||
|
"not enough memory for output buffer");
|
||
|
return 0;
|
||
|
}
|
||
|
str = PyString_FromStringAndSize(NULL, len*size*2);
|
||
|
if ( str == 0 )
|
||
|
return 0;
|
||
|
ncp = (signed char *)PyString_AsString(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) = (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);
|
||
|
}
|