| |
| /* audioopmodule - Module to detect peak values in arrays */ |
| |
| #define PY_SSIZE_T_CLEAN |
| |
| #include "Python.h" |
| |
| 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 |
| |
| static const int maxvals[] = {0, 0x7F, 0x7FFF, 0x7FFFFF, 0x7FFFFFFF}; |
| /* -1 trick is needed on Windows to support -0x80000000 without a warning */ |
| static const int minvals[] = {0, -0x80, -0x8000, -0x800000, -0x7FFFFFFF-1}; |
| static const unsigned int masks[] = {0, 0xFF, 0xFFFF, 0xFFFFFF, 0xFFFFFFFF}; |
| |
| static int |
| fbound(double val, double minval, double maxval) |
| { |
| if (val > maxval) |
| val = maxval; |
| else if (val < minval + 1) |
| val = minval; |
| return (int)val; |
| } |
| |
| |
| /* 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 an 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 const PyInt16 seg_aend[8] = { |
| 0x1F, 0x3F, 0x7F, 0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF |
| }; |
| static const PyInt16 seg_uend[8] = { |
| 0x3F, 0x7F, 0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF |
| }; |
| |
| static PyInt16 |
| search(PyInt16 val, const 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 const 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 an 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; |
| |
| /* 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 const 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 a 13-bit signed integer and encodes it as A-law data |
| * stored in an 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; |
| |
| /* 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 const int indexTable[16] = { |
| -1, -1, -1, -1, 2, 4, 6, 8, |
| -1, -1, -1, -1, 2, 4, 6, 8, |
| }; |
| |
| static const 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 GETINTX(T, cp, i) (*(T *)((unsigned char *)(cp) + (i))) |
| #define SETINTX(T, cp, i, val) do { \ |
| *(T *)((unsigned char *)(cp) + (i)) = (T)(val); \ |
| } while (0) |
| |
| |
| #define GETINT8(cp, i) GETINTX(signed char, (cp), (i)) |
| #define GETINT16(cp, i) GETINTX(short, (cp), (i)) |
| #define GETINT32(cp, i) GETINTX(PY_INT32_T, (cp), (i)) |
| |
| #if WORDS_BIGENDIAN |
| #define GETINT24(cp, i) ( \ |
| ((unsigned char *)(cp) + (i))[2] + \ |
| (((unsigned char *)(cp) + (i))[1] << 8) + \ |
| (((signed char *)(cp) + (i))[0] << 16) ) |
| #else |
| #define GETINT24(cp, i) ( \ |
| ((unsigned char *)(cp) + (i))[0] + \ |
| (((unsigned char *)(cp) + (i))[1] << 8) + \ |
| (((signed char *)(cp) + (i))[2] << 16) ) |
| #endif |
| |
| |
| #define SETINT8(cp, i, val) SETINTX(signed char, (cp), (i), (val)) |
| #define SETINT16(cp, i, val) SETINTX(short, (cp), (i), (val)) |
| #define SETINT32(cp, i, val) SETINTX(PY_INT32_T, (cp), (i), (val)) |
| |
| #if WORDS_BIGENDIAN |
| #define SETINT24(cp, i, val) do { \ |
| ((unsigned char *)(cp) + (i))[2] = (int)(val); \ |
| ((unsigned char *)(cp) + (i))[1] = (int)(val) >> 8; \ |
| ((signed char *)(cp) + (i))[0] = (int)(val) >> 16; \ |
| } while (0) |
| #else |
| #define SETINT24(cp, i, val) do { \ |
| ((unsigned char *)(cp) + (i))[0] = (int)(val); \ |
| ((unsigned char *)(cp) + (i))[1] = (int)(val) >> 8; \ |
| ((signed char *)(cp) + (i))[2] = (int)(val) >> 16; \ |
| } while (0) |
| #endif |
| |
| |
| #define GETRAWSAMPLE(size, cp, i) ( \ |
| (size == 1) ? (int)GETINT8((cp), (i)) : \ |
| (size == 2) ? (int)GETINT16((cp), (i)) : \ |
| (size == 3) ? (int)GETINT24((cp), (i)) : \ |
| (int)GETINT32((cp), (i))) |
| |
| #define SETRAWSAMPLE(size, cp, i, val) do { \ |
| if (size == 1) \ |
| SETINT8((cp), (i), (val)); \ |
| else if (size == 2) \ |
| SETINT16((cp), (i), (val)); \ |
| else if (size == 3) \ |
| SETINT24((cp), (i), (val)); \ |
| else \ |
| SETINT32((cp), (i), (val)); \ |
| } while(0) |
| |
| |
| #define GETSAMPLE32(size, cp, i) ( \ |
| (size == 1) ? (int)GETINT8((cp), (i)) << 24 : \ |
| (size == 2) ? (int)GETINT16((cp), (i)) << 16 : \ |
| (size == 3) ? (int)GETINT24((cp), (i)) << 8 : \ |
| (int)GETINT32((cp), (i))) |
| |
| #define SETSAMPLE32(size, cp, i, val) do { \ |
| if (size == 1) \ |
| SETINT8((cp), (i), (val) >> 24); \ |
| else if (size == 2) \ |
| SETINT16((cp), (i), (val) >> 16); \ |
| else if (size == 3) \ |
| SETINT24((cp), (i), (val) >> 8); \ |
| else \ |
| SETINT32((cp), (i), (val)); \ |
| } while(0) |
| |
| |
| static PyObject *AudioopError; |
| |
| static int |
| audioop_check_size(int size) |
| { |
| if (size < 1 || size > 4) { |
| PyErr_SetString(AudioopError, "Size should be 1, 2, 3 or 4"); |
| return 0; |
| } |
| else |
| return 1; |
| } |
| |
| static int |
| audioop_check_parameters(Py_ssize_t len, int size) |
| { |
| if (!audioop_check_size(size)) |
| return 0; |
| if (len % size != 0) { |
| PyErr_SetString(AudioopError, "not a whole number of frames"); |
| return 0; |
| } |
| return 1; |
| } |
| |
| /*[clinic input] |
| module audioop |
| [clinic start generated code]*/ |
| /*[clinic end generated code: output=da39a3ee5e6b4b0d input=8fa8f6611be3591a]*/ |
| |
| /*[clinic input] |
| audioop.getsample |
| |
| fragment: Py_buffer |
| width: int |
| index: Py_ssize_t |
| / |
| |
| Return the value of sample index from the fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_getsample_impl(PyModuleDef *module, Py_buffer *fragment, int width, |
| Py_ssize_t index) |
| /*[clinic end generated code: output=3995e189fdc8ec16 input=88edbe2871393549]*/ |
| { |
| int val; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| if (index < 0 || index >= fragment->len/width) { |
| PyErr_SetString(AudioopError, "Index out of range"); |
| return NULL; |
| } |
| val = GETRAWSAMPLE(width, fragment->buf, index*width); |
| return PyLong_FromLong(val); |
| } |
| |
| /*[clinic input] |
| audioop.max |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Return the maximum of the absolute value of all samples in a fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_max_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=85047ee1001f2305 input=32bea5ea0ac8c223]*/ |
| { |
| Py_ssize_t i; |
| unsigned int absval, max = 0; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| for (i = 0; i < fragment->len; i += width) { |
| int val = GETRAWSAMPLE(width, fragment->buf, i); |
| if (val < 0) absval = (-val); |
| else absval = val; |
| if (absval > max) max = absval; |
| } |
| return PyLong_FromUnsignedLong(max); |
| } |
| |
| /*[clinic input] |
| audioop.minmax |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Return the minimum and maximum values of all samples in the sound fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_minmax_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=ae8f5513c64fd569 input=89848e9b927a0696]*/ |
| { |
| Py_ssize_t i; |
| /* -1 trick below is needed on Windows to support -0x80000000 without |
| a warning */ |
| int min = 0x7fffffff, max = -0x7FFFFFFF-1; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| for (i = 0; i < fragment->len; i += width) { |
| int val = GETRAWSAMPLE(width, fragment->buf, i); |
| if (val > max) max = val; |
| if (val < min) min = val; |
| } |
| return Py_BuildValue("(ii)", min, max); |
| } |
| |
| /*[clinic input] |
| audioop.avg |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Return the average over all samples in the fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_avg_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=7fccd645c95f4860 input=1114493c7611334d]*/ |
| { |
| Py_ssize_t i; |
| int avg; |
| double sum = 0.0; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| for (i = 0; i < fragment->len; i += width) |
| sum += GETRAWSAMPLE(width, fragment->buf, i); |
| if (fragment->len == 0) |
| avg = 0; |
| else |
| avg = (int)floor(sum / (double)(fragment->len/width)); |
| return PyLong_FromLong(avg); |
| } |
| |
| /*[clinic input] |
| audioop.rms |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Return the root-mean-square of the fragment, i.e. sqrt(sum(S_i^2)/n). |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_rms_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=7b398702c81b709d input=4cc57c6c94219d78]*/ |
| { |
| Py_ssize_t i; |
| unsigned int res; |
| double sum_squares = 0.0; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| for (i = 0; i < fragment->len; i += width) { |
| double val = GETRAWSAMPLE(width, fragment->buf, i); |
| sum_squares += val*val; |
| } |
| if (fragment->len == 0) |
| res = 0; |
| else |
| res = (unsigned int)sqrt(sum_squares / (double)(fragment->len/width)); |
| return PyLong_FromUnsignedLong(res); |
| } |
| |
| static double _sum2(const short *a, const short *b, Py_ssize_t len) |
| { |
| Py_ssize_t 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. |
| */ |
| /*[clinic input] |
| audioop.findfit |
| |
| fragment: Py_buffer |
| reference: Py_buffer |
| / |
| |
| Try to match reference as well as possible to a portion of fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_findfit_impl(PyModuleDef *module, Py_buffer *fragment, |
| Py_buffer *reference) |
| /*[clinic end generated code: output=609eedf5d823d6dd input=62c305605e183c9a]*/ |
| { |
| const short *cp1, *cp2; |
| Py_ssize_t len1, len2; |
| Py_ssize_t j, best_j; |
| double aj_m1, aj_lm1; |
| double sum_ri_2, sum_aij_2, sum_aij_ri, result, best_result, factor; |
| |
| if (fragment->len & 1 || reference->len & 1) { |
| PyErr_SetString(AudioopError, "Strings should be even-sized"); |
| return NULL; |
| } |
| cp1 = (const short *)fragment->buf; |
| len1 = fragment->len >> 1; |
| cp2 = (const short *)reference->buf; |
| len2 = reference->len >> 1; |
| |
| if (len1 < len2) { |
| PyErr_SetString(AudioopError, "First sample should be longer"); |
| return NULL; |
| } |
| 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("(nf)", best_j, factor); |
| } |
| |
| /* |
| ** findfactor finds a factor f so that the energy in A-fB is minimal. |
| ** See the comment for findfit for details. |
| */ |
| /*[clinic input] |
| audioop.findfactor |
| |
| fragment: Py_buffer |
| reference: Py_buffer |
| / |
| |
| Return a factor F such that rms(add(fragment, mul(reference, -F))) is minimal. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_findfactor_impl(PyModuleDef *module, Py_buffer *fragment, |
| Py_buffer *reference) |
| /*[clinic end generated code: output=5566a8c55de54f99 input=816680301d012b21]*/ |
| { |
| const short *cp1, *cp2; |
| Py_ssize_t len; |
| double sum_ri_2, sum_aij_ri, result; |
| |
| if (fragment->len & 1 || reference->len & 1) { |
| PyErr_SetString(AudioopError, "Strings should be even-sized"); |
| return NULL; |
| } |
| if (fragment->len != reference->len) { |
| PyErr_SetString(AudioopError, "Samples should be same size"); |
| return NULL; |
| } |
| cp1 = (const short *)fragment->buf; |
| cp2 = (const short *)reference->buf; |
| len = fragment->len >> 1; |
| sum_ri_2 = _sum2(cp2, cp2, len); |
| sum_aij_ri = _sum2(cp1, cp2, len); |
| |
| 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. |
| */ |
| /*[clinic input] |
| audioop.findmax |
| |
| fragment: Py_buffer |
| length: Py_ssize_t |
| / |
| |
| Search fragment for a slice of specified number of samples with maximum energy. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_findmax_impl(PyModuleDef *module, Py_buffer *fragment, |
| Py_ssize_t length) |
| /*[clinic end generated code: output=01fe796fad2573bb input=2f304801ed42383c]*/ |
| { |
| const short *cp1; |
| Py_ssize_t len1; |
| Py_ssize_t j, best_j; |
| double aj_m1, aj_lm1; |
| double result, best_result; |
| |
| if (fragment->len & 1) { |
| PyErr_SetString(AudioopError, "Strings should be even-sized"); |
| return NULL; |
| } |
| cp1 = (const short *)fragment->buf; |
| len1 = fragment->len >> 1; |
| |
| if (length < 0 || len1 < length) { |
| PyErr_SetString(AudioopError, "Input sample should be longer"); |
| return NULL; |
| } |
| |
| result = _sum2(cp1, cp1, length); |
| |
| best_result = result; |
| best_j = 0; |
| |
| for ( j=1; j<=len1-length; j++) { |
| aj_m1 = (double)cp1[j-1]; |
| aj_lm1 = (double)cp1[j+length-1]; |
| |
| result = result + aj_lm1*aj_lm1 - aj_m1*aj_m1; |
| |
| if ( result > best_result ) { |
| best_result = result; |
| best_j = j; |
| } |
| |
| } |
| |
| return PyLong_FromSsize_t(best_j); |
| } |
| |
| /*[clinic input] |
| audioop.avgpp |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Return the average peak-peak value over all samples in the fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_avgpp_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=06c8380fd6e34207 input=0b3cceeae420a7d9]*/ |
| { |
| Py_ssize_t i; |
| int prevval, prevextremevalid = 0, prevextreme = 0; |
| double sum = 0.0; |
| unsigned int avg; |
| int diff, prevdiff, nextreme = 0; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| if (fragment->len <= width) |
| return PyLong_FromLong(0); |
| prevval = GETRAWSAMPLE(width, fragment->buf, 0); |
| prevdiff = 17; /* Anything != 0, 1 */ |
| for (i = width; i < fragment->len; i += width) { |
| int val = GETRAWSAMPLE(width, fragment->buf, 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) |
| sum += (double)((unsigned int)prevextreme - |
| (unsigned int)prevval); |
| else |
| sum += (double)((unsigned int)prevval - |
| (unsigned int)prevextreme); |
| nextreme++; |
| } |
| prevextremevalid = 1; |
| prevextreme = prevval; |
| } |
| prevval = val; |
| prevdiff = diff; |
| } |
| } |
| if ( nextreme == 0 ) |
| avg = 0; |
| else |
| avg = (unsigned int)(sum / (double)nextreme); |
| return PyLong_FromUnsignedLong(avg); |
| } |
| |
| /*[clinic input] |
| audioop.maxpp |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Return the maximum peak-peak value in the sound fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_maxpp_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=c300c0bd7e8535c0 input=671a13e1518f80a1]*/ |
| { |
| Py_ssize_t i; |
| int prevval, prevextremevalid = 0, prevextreme = 0; |
| unsigned int max = 0, extremediff; |
| int diff, prevdiff; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| if (fragment->len <= width) |
| return PyLong_FromLong(0); |
| prevval = GETRAWSAMPLE(width, fragment->buf, 0); |
| prevdiff = 17; /* Anything != 0, 1 */ |
| for (i = width; i < fragment->len; i += width) { |
| int val = GETRAWSAMPLE(width, fragment->buf, 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; |
| } |
| } |
| return PyLong_FromUnsignedLong(max); |
| } |
| |
| /*[clinic input] |
| audioop.cross |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Return the number of zero crossings in the fragment passed as an argument. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_cross_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=99e6572d7d7cdbf1 input=b1b3f15b83f6b41a]*/ |
| { |
| Py_ssize_t i; |
| int prevval; |
| Py_ssize_t ncross; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| ncross = -1; |
| prevval = 17; /* Anything <> 0,1 */ |
| for (i = 0; i < fragment->len; i += width) { |
| int val = GETRAWSAMPLE(width, fragment->buf, i) < 0; |
| if (val != prevval) ncross++; |
| prevval = val; |
| } |
| return PyLong_FromSsize_t(ncross); |
| } |
| |
| /*[clinic input] |
| audioop.mul |
| |
| fragment: Py_buffer |
| width: int |
| factor: double |
| / |
| |
| Return a fragment that has all samples in the original fragment multiplied by the floating-point value factor. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_mul_impl(PyModuleDef *module, Py_buffer *fragment, int width, |
| double factor) |
| /*[clinic end generated code: output=1c7c31191ac86b10 input=c726667baa157d3c]*/ |
| { |
| signed char *ncp; |
| Py_ssize_t i; |
| double maxval, minval; |
| PyObject *rv; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| |
| maxval = (double) maxvals[width]; |
| minval = (double) minvals[width]; |
| |
| rv = PyBytes_FromStringAndSize(NULL, fragment->len); |
| if (rv == NULL) |
| return NULL; |
| ncp = (signed char *)PyBytes_AsString(rv); |
| |
| for (i = 0; i < fragment->len; i += width) { |
| double val = GETRAWSAMPLE(width, fragment->buf, i); |
| val *= factor; |
| val = floor(fbound(val, minval, maxval)); |
| SETRAWSAMPLE(width, ncp, i, (int)val); |
| } |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.tomono |
| |
| fragment: Py_buffer |
| width: int |
| lfactor: double |
| rfactor: double |
| / |
| |
| Convert a stereo fragment to a mono fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_tomono_impl(PyModuleDef *module, Py_buffer *fragment, int width, |
| double lfactor, double rfactor) |
| /*[clinic end generated code: output=553f547c5e29e3b6 input=c4ec949b3f4dddfa]*/ |
| { |
| signed char *cp, *ncp; |
| Py_ssize_t len, i; |
| double maxval, minval; |
| PyObject *rv; |
| |
| cp = fragment->buf; |
| len = fragment->len; |
| if (!audioop_check_parameters(len, width)) |
| return NULL; |
| if (((len / width) & 1) != 0) { |
| PyErr_SetString(AudioopError, "not a whole number of frames"); |
| return NULL; |
| } |
| |
| maxval = (double) maxvals[width]; |
| minval = (double) minvals[width]; |
| |
| rv = PyBytes_FromStringAndSize(NULL, len/2); |
| if (rv == NULL) |
| return NULL; |
| ncp = (signed char *)PyBytes_AsString(rv); |
| |
| for (i = 0; i < len; i += width*2) { |
| double val1 = GETRAWSAMPLE(width, cp, i); |
| double val2 = GETRAWSAMPLE(width, cp, i + width); |
| double val = val1*lfactor + val2*rfactor; |
| val = floor(fbound(val, minval, maxval)); |
| SETRAWSAMPLE(width, ncp, i/2, val); |
| } |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.tostereo |
| |
| fragment: Py_buffer |
| width: int |
| lfactor: double |
| rfactor: double |
| / |
| |
| Generate a stereo fragment from a mono fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_tostereo_impl(PyModuleDef *module, Py_buffer *fragment, int width, |
| double lfactor, double rfactor) |
| /*[clinic end generated code: output=697bb6ba41e9dd2c input=27b6395ebfdff37a]*/ |
| { |
| signed char *ncp; |
| Py_ssize_t i; |
| double maxval, minval; |
| PyObject *rv; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| |
| maxval = (double) maxvals[width]; |
| minval = (double) minvals[width]; |
| |
| if (fragment->len > PY_SSIZE_T_MAX/2) { |
| PyErr_SetString(PyExc_MemoryError, |
| "not enough memory for output buffer"); |
| return NULL; |
| } |
| |
| rv = PyBytes_FromStringAndSize(NULL, fragment->len*2); |
| if (rv == NULL) |
| return NULL; |
| ncp = (signed char *)PyBytes_AsString(rv); |
| |
| for (i = 0; i < fragment->len; i += width) { |
| double val = GETRAWSAMPLE(width, fragment->buf, i); |
| int val1 = (int)floor(fbound(val*lfactor, minval, maxval)); |
| int val2 = (int)floor(fbound(val*rfactor, minval, maxval)); |
| SETRAWSAMPLE(width, ncp, i*2, val1); |
| SETRAWSAMPLE(width, ncp, i*2 + width, val2); |
| } |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.add |
| |
| fragment1: Py_buffer |
| fragment2: Py_buffer |
| width: int |
| / |
| |
| Return a fragment which is the addition of the two samples passed as parameters. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_add_impl(PyModuleDef *module, Py_buffer *fragment1, |
| Py_buffer *fragment2, int width) |
| /*[clinic end generated code: output=fe6c12f143e0b027 input=4a8d4bae4c1605c7]*/ |
| { |
| signed char *ncp; |
| Py_ssize_t i; |
| int minval, maxval, newval; |
| PyObject *rv; |
| |
| if (!audioop_check_parameters(fragment1->len, width)) |
| return NULL; |
| if (fragment1->len != fragment2->len) { |
| PyErr_SetString(AudioopError, "Lengths should be the same"); |
| return NULL; |
| } |
| |
| maxval = maxvals[width]; |
| minval = minvals[width]; |
| |
| rv = PyBytes_FromStringAndSize(NULL, fragment1->len); |
| if (rv == NULL) |
| return NULL; |
| ncp = (signed char *)PyBytes_AsString(rv); |
| |
| for (i = 0; i < fragment1->len; i += width) { |
| int val1 = GETRAWSAMPLE(width, fragment1->buf, i); |
| int val2 = GETRAWSAMPLE(width, fragment2->buf, i); |
| |
| if (width < 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)); |
| } |
| |
| SETRAWSAMPLE(width, ncp, i, newval); |
| } |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.bias |
| |
| fragment: Py_buffer |
| width: int |
| bias: int |
| / |
| |
| Return a fragment that is the original fragment with a bias added to each sample. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_bias_impl(PyModuleDef *module, Py_buffer *fragment, int width, |
| int bias) |
| /*[clinic end generated code: output=ac1f4dda20a01c26 input=2b5cce5c3bb4838c]*/ |
| { |
| signed char *ncp; |
| Py_ssize_t i; |
| unsigned int val = 0, mask; |
| PyObject *rv; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| |
| rv = PyBytes_FromStringAndSize(NULL, fragment->len); |
| if (rv == NULL) |
| return NULL; |
| ncp = (signed char *)PyBytes_AsString(rv); |
| |
| mask = masks[width]; |
| |
| for (i = 0; i < fragment->len; i += width) { |
| if (width == 1) |
| val = GETINTX(unsigned char, fragment->buf, i); |
| else if (width == 2) |
| val = GETINTX(unsigned short, fragment->buf, i); |
| else if (width == 3) |
| val = ((unsigned int)GETINT24(fragment->buf, i)) & 0xffffffu; |
| else { |
| assert(width == 4); |
| val = GETINTX(PY_UINT32_T, fragment->buf, i); |
| } |
| |
| val += (unsigned int)bias; |
| /* wrap around in case of overflow */ |
| val &= mask; |
| |
| if (width == 1) |
| SETINTX(unsigned char, ncp, i, val); |
| else if (width == 2) |
| SETINTX(unsigned short, ncp, i, val); |
| else if (width == 3) |
| SETINT24(ncp, i, (int)val); |
| else { |
| assert(width == 4); |
| SETINTX(PY_UINT32_T, ncp, i, val); |
| } |
| } |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.reverse |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Reverse the samples in a fragment and returns the modified fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_reverse_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=6ec3c91337f5925e input=668f890cf9f9d225]*/ |
| { |
| unsigned char *ncp; |
| Py_ssize_t i; |
| PyObject *rv; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| |
| rv = PyBytes_FromStringAndSize(NULL, fragment->len); |
| if (rv == NULL) |
| return NULL; |
| ncp = (unsigned char *)PyBytes_AsString(rv); |
| |
| for (i = 0; i < fragment->len; i += width) { |
| int val = GETRAWSAMPLE(width, fragment->buf, i); |
| SETRAWSAMPLE(width, ncp, fragment->len - i - width, val); |
| } |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.byteswap |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Convert big-endian samples to little-endian and vice versa. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_byteswap_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=bfe4aa584b7a3f5b input=fae7611ceffa5c82]*/ |
| { |
| unsigned char *ncp; |
| Py_ssize_t i; |
| PyObject *rv; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| |
| rv = PyBytes_FromStringAndSize(NULL, fragment->len); |
| if (rv == NULL) |
| return NULL; |
| ncp = (unsigned char *)PyBytes_AsString(rv); |
| |
| for (i = 0; i < fragment->len; i += width) { |
| int j; |
| for (j = 0; j < width; j++) |
| ncp[i + width - 1 - j] = ((unsigned char *)fragment->buf)[i + j]; |
| } |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.lin2lin |
| |
| fragment: Py_buffer |
| width: int |
| newwidth: int |
| / |
| |
| Convert samples between 1-, 2-, 3- and 4-byte formats. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_lin2lin_impl(PyModuleDef *module, Py_buffer *fragment, int width, |
| int newwidth) |
| /*[clinic end generated code: output=cb6ca950d1df9898 input=5ce08c8aa2f24d96]*/ |
| { |
| unsigned char *ncp; |
| Py_ssize_t i, j; |
| PyObject *rv; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| if (!audioop_check_size(newwidth)) |
| return NULL; |
| |
| if (fragment->len/width > PY_SSIZE_T_MAX/newwidth) { |
| PyErr_SetString(PyExc_MemoryError, |
| "not enough memory for output buffer"); |
| return NULL; |
| } |
| rv = PyBytes_FromStringAndSize(NULL, (fragment->len/width)*newwidth); |
| if (rv == NULL) |
| return NULL; |
| ncp = (unsigned char *)PyBytes_AsString(rv); |
| |
| for (i = j = 0; i < fragment->len; i += width, j += newwidth) { |
| int val = GETSAMPLE32(width, fragment->buf, i); |
| SETSAMPLE32(newwidth, ncp, j, val); |
| } |
| return rv; |
| } |
| |
| static int |
| gcd(int a, int b) |
| { |
| while (b > 0) { |
| int tmp = a % b; |
| a = b; |
| b = tmp; |
| } |
| return a; |
| } |
| |
| /*[clinic input] |
| audioop.ratecv |
| |
| fragment: Py_buffer |
| width: int |
| nchannels: int |
| inrate: int |
| outrate: int |
| state: object |
| weightA: int = 1 |
| weightB: int = 0 |
| / |
| |
| Convert the frame rate of the input fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_ratecv_impl(PyModuleDef *module, Py_buffer *fragment, int width, |
| int nchannels, int inrate, int outrate, PyObject *state, |
| int weightA, int weightB) |
| /*[clinic end generated code: output=59e1787bfa49b9d9 input=aff3acdc94476191]*/ |
| { |
| char *cp, *ncp; |
| Py_ssize_t len; |
| int chan, d, *prev_i, *cur_i, cur_o; |
| PyObject *samps, *str, *rv = NULL; |
| int bytes_per_frame; |
| |
| if (!audioop_check_size(width)) |
| return NULL; |
| if (nchannels < 1) { |
| PyErr_SetString(AudioopError, "# of channels should be >= 1"); |
| return NULL; |
| } |
| if (width > INT_MAX / nchannels) { |
| /* 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; |
| } |
| bytes_per_frame = width * nchannels; |
| if (weightA < 1 || weightB < 0) { |
| PyErr_SetString(AudioopError, |
| "weightA should be >= 1, weightB should be >= 0"); |
| return NULL; |
| } |
| assert(fragment->len >= 0); |
| if (fragment->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; |
| weightB /= d; |
| |
| if ((size_t)nchannels > PY_SIZE_MAX/sizeof(int)) { |
| PyErr_SetString(PyExc_MemoryError, |
| "not enough memory for output buffer"); |
| return NULL; |
| } |
| prev_i = (int *) PyMem_Malloc(nchannels * sizeof(int)); |
| cur_i = (int *) PyMem_Malloc(nchannels * sizeof(int)); |
| if (prev_i == NULL || cur_i == NULL) { |
| (void) PyErr_NoMemory(); |
| goto exit; |
| } |
| |
| len = fragment->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 = PyBytes_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 */ |
| Py_ssize_t q = 1 + (len - 1) / inrate; |
| if (outrate > PY_SSIZE_T_MAX / q / bytes_per_frame) |
| str = NULL; |
| else |
| str = PyBytes_FromStringAndSize(NULL, |
| q * outrate * bytes_per_frame); |
| } |
| if (str == NULL) { |
| PyErr_SetString(PyExc_MemoryError, |
| "not enough memory for output buffer"); |
| goto exit; |
| } |
| ncp = PyBytes_AsString(str); |
| cp = fragment->buf; |
| |
| 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 = (Py_ssize_t)(ncp - PyBytes_AsString(str)); |
| rv = PyBytes_FromStringAndSize |
| (PyBytes_AsString(str), len); |
| Py_DECREF(str); |
| str = rv; |
| if (str == NULL) |
| 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]; |
| cur_i[chan] = GETSAMPLE32(width, cp, 0); |
| cp += width; |
| /* 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); |
| SETSAMPLE32(width, ncp, 0, cur_o); |
| ncp += width; |
| } |
| d -= inrate; |
| } |
| } |
| exit: |
| PyMem_Free(prev_i); |
| PyMem_Free(cur_i); |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.lin2ulaw |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Convert samples in the audio fragment to u-LAW encoding. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_lin2ulaw_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=26263cc877c5e1bc input=2450d1b870b6bac2]*/ |
| { |
| unsigned char *ncp; |
| Py_ssize_t i; |
| PyObject *rv; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| |
| rv = PyBytes_FromStringAndSize(NULL, fragment->len/width); |
| if (rv == NULL) |
| return NULL; |
| ncp = (unsigned char *)PyBytes_AsString(rv); |
| |
| for (i = 0; i < fragment->len; i += width) { |
| int val = GETSAMPLE32(width, fragment->buf, i); |
| *ncp++ = st_14linear2ulaw(val >> 18); |
| } |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.ulaw2lin |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Convert sound fragments in u-LAW encoding to linearly encoded sound fragments. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_ulaw2lin_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=9864cb34e3a1d876 input=45d53ddce5be7d06]*/ |
| { |
| unsigned char *cp; |
| signed char *ncp; |
| Py_ssize_t i; |
| PyObject *rv; |
| |
| if (!audioop_check_size(width)) |
| return NULL; |
| |
| if (fragment->len > PY_SSIZE_T_MAX/width) { |
| PyErr_SetString(PyExc_MemoryError, |
| "not enough memory for output buffer"); |
| return NULL; |
| } |
| rv = PyBytes_FromStringAndSize(NULL, fragment->len*width); |
| if (rv == NULL) |
| return NULL; |
| ncp = (signed char *)PyBytes_AsString(rv); |
| |
| cp = fragment->buf; |
| for (i = 0; i < fragment->len*width; i += width) { |
| int val = st_ulaw2linear16(*cp++) << 16; |
| SETSAMPLE32(width, ncp, i, val); |
| } |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.lin2alaw |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Convert samples in the audio fragment to a-LAW encoding. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_lin2alaw_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=d5bf14bd0fe6fdcd input=ffb1ef8bb39da945]*/ |
| { |
| unsigned char *ncp; |
| Py_ssize_t i; |
| PyObject *rv; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| |
| rv = PyBytes_FromStringAndSize(NULL, fragment->len/width); |
| if (rv == NULL) |
| return NULL; |
| ncp = (unsigned char *)PyBytes_AsString(rv); |
| |
| for (i = 0; i < fragment->len; i += width) { |
| int val = GETSAMPLE32(width, fragment->buf, i); |
| *ncp++ = st_linear2alaw(val >> 19); |
| } |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.alaw2lin |
| |
| fragment: Py_buffer |
| width: int |
| / |
| |
| Convert sound fragments in a-LAW encoding to linearly encoded sound fragments. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_alaw2lin_impl(PyModuleDef *module, Py_buffer *fragment, int width) |
| /*[clinic end generated code: output=d2b604ddd036e1cd input=4140626046cd1772]*/ |
| { |
| unsigned char *cp; |
| signed char *ncp; |
| Py_ssize_t i; |
| int val; |
| PyObject *rv; |
| |
| if (!audioop_check_size(width)) |
| return NULL; |
| |
| if (fragment->len > PY_SSIZE_T_MAX/width) { |
| PyErr_SetString(PyExc_MemoryError, |
| "not enough memory for output buffer"); |
| return NULL; |
| } |
| rv = PyBytes_FromStringAndSize(NULL, fragment->len*width); |
| if (rv == NULL) |
| return NULL; |
| ncp = (signed char *)PyBytes_AsString(rv); |
| cp = fragment->buf; |
| |
| for (i = 0; i < fragment->len*width; i += width) { |
| val = st_alaw2linear16(*cp++) << 16; |
| SETSAMPLE32(width, ncp, i, val); |
| } |
| return rv; |
| } |
| |
| /*[clinic input] |
| audioop.lin2adpcm |
| |
| fragment: Py_buffer |
| width: int |
| state: object |
| / |
| |
| Convert samples to 4 bit Intel/DVI ADPCM encoding. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_lin2adpcm_impl(PyModuleDef *module, Py_buffer *fragment, int width, |
| PyObject *state) |
| /*[clinic end generated code: output=93f0996f592b5ce5 input=12919d549b90c90a]*/ |
| { |
| signed char *ncp; |
| Py_ssize_t i; |
| int step, valpred, delta, |
| index, sign, vpdiff, diff; |
| PyObject *rv = NULL, *str; |
| int outputbuffer = 0, bufferstep; |
| |
| if (!audioop_check_parameters(fragment->len, width)) |
| return NULL; |
| |
| /* Decode state, should have (value, step) */ |
| if ( state == Py_None ) { |
| /* First time, it seems. Set defaults */ |
| valpred = 0; |
| index = 0; |
| } |
| else if (!PyTuple_Check(state)) { |
| PyErr_SetString(PyExc_TypeError, "state must be a tuple or None"); |
| return NULL; |
| } |
| else if (!PyArg_ParseTuple(state, "ii", &valpred, &index)) { |
| return NULL; |
| } |
| else if (valpred >= 0x8000 || valpred < -0x8000 || |
| (size_t)index >= Py_ARRAY_LENGTH(stepsizeTable)) { |
| PyErr_SetString(PyExc_ValueError, "bad state"); |
| return NULL; |
| } |
| |
| str = PyBytes_FromStringAndSize(NULL, fragment->len/(width*2)); |
| if (str == NULL) |
| return NULL; |
| ncp = (signed char *)PyBytes_AsString(str); |
| |
| step = stepsizeTable[index]; |
| bufferstep = 1; |
| |
| for (i = 0; i < fragment->len; i += width) { |
| int val = GETSAMPLE32(width, fragment->buf, i) >> 16; |
| |
| /* Step 1 - compute difference with previous value */ |
| if (val < valpred) { |
| diff = valpred - val; |
| sign = 8; |
| } |
| else { |
| diff = val - valpred; |
| sign = 0; |
| } |
| |
| /* 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; |
| } |
| |
| /*[clinic input] |
| audioop.adpcm2lin |
| |
| fragment: Py_buffer |
| width: int |
| state: object |
| / |
| |
| Decode an Intel/DVI ADPCM coded fragment to a linear fragment. |
| [clinic start generated code]*/ |
| |
| static PyObject * |
| audioop_adpcm2lin_impl(PyModuleDef *module, Py_buffer *fragment, int width, |
| PyObject *state) |
| /*[clinic end generated code: output=236cf6dc2c829181 input=f5221144f5ca9ef0]*/ |
| { |
| signed char *cp; |
| signed char *ncp; |
| Py_ssize_t i, outlen; |
| int valpred, step, delta, index, sign, vpdiff; |
| PyObject *rv, *str; |
| int inputbuffer = 0, bufferstep; |
| |
| if (!audioop_check_size(width)) |
| return NULL; |
| |
| /* Decode state, should have (value, step) */ |
| if ( state == Py_None ) { |
| /* First time, it seems. Set defaults */ |
| valpred = 0; |
| index = 0; |
| } |
| else if (!PyTuple_Check(state)) { |
| PyErr_SetString(PyExc_TypeError, "state must be a tuple or None"); |
| return NULL; |
| } |
| else if (!PyArg_ParseTuple(state, "ii", &valpred, &index)) { |
| return NULL; |
| } |
| else if (valpred >= 0x8000 || valpred < -0x8000 || |
| (size_t)index >= Py_ARRAY_LENGTH(stepsizeTable)) { |
| PyErr_SetString(PyExc_ValueError, "bad state"); |
| return NULL; |
| } |
| |
| if (fragment->len > (PY_SSIZE_T_MAX/2)/width) { |
| PyErr_SetString(PyExc_MemoryError, |
| "not enough memory for output buffer"); |
| return NULL; |
| } |
| outlen = fragment->len*width*2; |
| str = PyBytes_FromStringAndSize(NULL, outlen); |
| if (str == NULL) |
| return NULL; |
| ncp = (signed char *)PyBytes_AsString(str); |
| cp = fragment->buf; |
| |
| step = stepsizeTable[index]; |
| bufferstep = 0; |
| |
| for (i = 0; i < outlen; i += width) { |
| /* 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 */ |
| SETSAMPLE32(width, ncp, i, valpred << 16); |
| } |
| |
| rv = Py_BuildValue("(O(ii))", str, valpred, index); |
| Py_DECREF(str); |
| return rv; |
| } |
| |
| #include "clinic/audioop.c.h" |
| |
| static PyMethodDef audioop_methods[] = { |
| AUDIOOP_MAX_METHODDEF |
| AUDIOOP_MINMAX_METHODDEF |
| AUDIOOP_AVG_METHODDEF |
| AUDIOOP_MAXPP_METHODDEF |
| AUDIOOP_AVGPP_METHODDEF |
| AUDIOOP_RMS_METHODDEF |
| AUDIOOP_FINDFIT_METHODDEF |
| AUDIOOP_FINDMAX_METHODDEF |
| AUDIOOP_FINDFACTOR_METHODDEF |
| AUDIOOP_CROSS_METHODDEF |
| AUDIOOP_MUL_METHODDEF |
| AUDIOOP_ADD_METHODDEF |
| AUDIOOP_BIAS_METHODDEF |
| AUDIOOP_ULAW2LIN_METHODDEF |
| AUDIOOP_LIN2ULAW_METHODDEF |
| AUDIOOP_ALAW2LIN_METHODDEF |
| AUDIOOP_LIN2ALAW_METHODDEF |
| AUDIOOP_LIN2LIN_METHODDEF |
| AUDIOOP_ADPCM2LIN_METHODDEF |
| AUDIOOP_LIN2ADPCM_METHODDEF |
| AUDIOOP_TOMONO_METHODDEF |
| AUDIOOP_TOSTEREO_METHODDEF |
| AUDIOOP_GETSAMPLE_METHODDEF |
| AUDIOOP_REVERSE_METHODDEF |
| AUDIOOP_BYTESWAP_METHODDEF |
| AUDIOOP_RATECV_METHODDEF |
| { 0, 0 } |
| }; |
| |
| |
| static struct PyModuleDef audioopmodule = { |
| PyModuleDef_HEAD_INIT, |
| "audioop", |
| NULL, |
| -1, |
| audioop_methods, |
| NULL, |
| NULL, |
| NULL, |
| NULL |
| }; |
| |
| PyMODINIT_FUNC |
| PyInit_audioop(void) |
| { |
| PyObject *m, *d; |
| m = PyModule_Create(&audioopmodule); |
| if (m == NULL) |
| return NULL; |
| d = PyModule_GetDict(m); |
| if (d == NULL) |
| return NULL; |
| AudioopError = PyErr_NewException("audioop.error", NULL, NULL); |
| if (AudioopError != NULL) |
| PyDict_SetItemString(d,"error",AudioopError); |
| return m; |
| } |