|  |  | 
|  | /* | 
|  | * | 
|  | Copyright (c) Eicon Networks, 2002. | 
|  | * | 
|  | This source file is supplied for the use with | 
|  | Eicon Networks range of DIVA Server Adapters. | 
|  | * | 
|  | Eicon File Revision :    2.1 | 
|  | * | 
|  | This program is free software; you can redistribute it and/or modify | 
|  | it under the terms of the GNU General Public License as published by | 
|  | the Free Software Foundation; either version 2, or (at your option) | 
|  | any later version. | 
|  | * | 
|  | This program is distributed in the hope that it will be useful, | 
|  | but WITHOUT ANY WARRANTY OF ANY KIND WHATSOEVER INCLUDING ANY | 
|  | implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | 
|  | See the GNU General Public License for more details. | 
|  | * | 
|  | You should have received a copy of the GNU General Public License | 
|  | along with this program; if not, write to the Free Software | 
|  | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | 
|  | * | 
|  | */ | 
|  |  | 
|  | #include "platform.h" | 
|  |  | 
|  |  | 
|  |  | 
|  |  | 
|  |  | 
|  |  | 
|  |  | 
|  |  | 
|  |  | 
|  | #include "capidtmf.h" | 
|  |  | 
|  | /* #define TRACE_ */ | 
|  |  | 
|  | #define FILE_ "CAPIDTMF.C" | 
|  |  | 
|  | /*---------------------------------------------------------------------------*/ | 
|  |  | 
|  |  | 
|  | #define trace(a) | 
|  |  | 
|  |  | 
|  |  | 
|  | /*---------------------------------------------------------------------------*/ | 
|  |  | 
|  | static short capidtmf_expand_table_alaw[0x0100] = | 
|  | { | 
|  | -5504,   5504,   -344,    344, -22016,  22016,  -1376,   1376, | 
|  | -2752,   2752,    -88,     88, -11008,  11008,   -688,    688, | 
|  | -7552,   7552,   -472,    472, -30208,  30208,  -1888,   1888, | 
|  | -3776,   3776,   -216,    216, -15104,  15104,   -944,    944, | 
|  | -4480,   4480,   -280,    280, -17920,  17920,  -1120,   1120, | 
|  | -2240,   2240,    -24,     24,  -8960,   8960,   -560,    560, | 
|  | -6528,   6528,   -408,    408, -26112,  26112,  -1632,   1632, | 
|  | -3264,   3264,   -152,    152, -13056,  13056,   -816,    816, | 
|  | -6016,   6016,   -376,    376, -24064,  24064,  -1504,   1504, | 
|  | -3008,   3008,   -120,    120, -12032,  12032,   -752,    752, | 
|  | -8064,   8064,   -504,    504, -32256,  32256,  -2016,   2016, | 
|  | -4032,   4032,   -248,    248, -16128,  16128,  -1008,   1008, | 
|  | -4992,   4992,   -312,    312, -19968,  19968,  -1248,   1248, | 
|  | -2496,   2496,    -56,     56,  -9984,   9984,   -624,    624, | 
|  | -7040,   7040,   -440,    440, -28160,  28160,  -1760,   1760, | 
|  | -3520,   3520,   -184,    184, -14080,  14080,   -880,    880, | 
|  | -5248,   5248,   -328,    328, -20992,  20992,  -1312,   1312, | 
|  | -2624,   2624,    -72,     72, -10496,  10496,   -656,    656, | 
|  | -7296,   7296,   -456,    456, -29184,  29184,  -1824,   1824, | 
|  | -3648,   3648,   -200,    200, -14592,  14592,   -912,    912, | 
|  | -4224,   4224,   -264,    264, -16896,  16896,  -1056,   1056, | 
|  | -2112,   2112,     -8,      8,  -8448,   8448,   -528,    528, | 
|  | -6272,   6272,   -392,    392, -25088,  25088,  -1568,   1568, | 
|  | -3136,   3136,   -136,    136, -12544,  12544,   -784,    784, | 
|  | -5760,   5760,   -360,    360, -23040,  23040,  -1440,   1440, | 
|  | -2880,   2880,   -104,    104, -11520,  11520,   -720,    720, | 
|  | -7808,   7808,   -488,    488, -31232,  31232,  -1952,   1952, | 
|  | -3904,   3904,   -232,    232, -15616,  15616,   -976,    976, | 
|  | -4736,   4736,   -296,    296, -18944,  18944,  -1184,   1184, | 
|  | -2368,   2368,    -40,     40,  -9472,   9472,   -592,    592, | 
|  | -6784,   6784,   -424,    424, -27136,  27136,  -1696,   1696, | 
|  | -3392,   3392,   -168,    168, -13568,  13568,   -848,    848 | 
|  | }; | 
|  |  | 
|  | static short capidtmf_expand_table_ulaw[0x0100] = | 
|  | { | 
|  | -32124,  32124,  -1884,   1884,  -7932,   7932,   -372,    372, | 
|  | -15996,  15996,   -876,    876,  -3900,   3900,   -120,    120, | 
|  | -23932,  23932,  -1372,   1372,  -5884,   5884,   -244,    244, | 
|  | -11900,  11900,   -620,    620,  -2876,   2876,    -56,     56, | 
|  | -28028,  28028,  -1628,   1628,  -6908,   6908,   -308,    308, | 
|  | -13948,  13948,   -748,    748,  -3388,   3388,    -88,     88, | 
|  | -19836,  19836,  -1116,   1116,  -4860,   4860,   -180,    180, | 
|  | -9852,   9852,   -492,    492,  -2364,   2364,    -24,     24, | 
|  | -30076,  30076,  -1756,   1756,  -7420,   7420,   -340,    340, | 
|  | -14972,  14972,   -812,    812,  -3644,   3644,   -104,    104, | 
|  | -21884,  21884,  -1244,   1244,  -5372,   5372,   -212,    212, | 
|  | -10876,  10876,   -556,    556,  -2620,   2620,    -40,     40, | 
|  | -25980,  25980,  -1500,   1500,  -6396,   6396,   -276,    276, | 
|  | -12924,  12924,   -684,    684,  -3132,   3132,    -72,     72, | 
|  | -17788,  17788,   -988,    988,  -4348,   4348,   -148,    148, | 
|  | -8828,   8828,   -428,    428,  -2108,   2108,     -8,      8, | 
|  | -31100,  31100,  -1820,   1820,  -7676,   7676,   -356,    356, | 
|  | -15484,  15484,   -844,    844,  -3772,   3772,   -112,    112, | 
|  | -22908,  22908,  -1308,   1308,  -5628,   5628,   -228,    228, | 
|  | -11388,  11388,   -588,    588,  -2748,   2748,    -48,     48, | 
|  | -27004,  27004,  -1564,   1564,  -6652,   6652,   -292,    292, | 
|  | -13436,  13436,   -716,    716,  -3260,   3260,    -80,     80, | 
|  | -18812,  18812,  -1052,   1052,  -4604,   4604,   -164,    164, | 
|  | -9340,   9340,   -460,    460,  -2236,   2236,    -16,     16, | 
|  | -29052,  29052,  -1692,   1692,  -7164,   7164,   -324,    324, | 
|  | -14460,  14460,   -780,    780,  -3516,   3516,    -96,     96, | 
|  | -20860,  20860,  -1180,   1180,  -5116,   5116,   -196,    196, | 
|  | -10364,  10364,   -524,    524,  -2492,   2492,    -32,     32, | 
|  | -24956,  24956,  -1436,   1436,  -6140,   6140,   -260,    260, | 
|  | -12412,  12412,   -652,    652,  -3004,   3004,    -64,     64, | 
|  | -16764,  16764,   -924,    924,  -4092,   4092,   -132,    132, | 
|  | -8316,   8316,   -396,    396,  -1980,   1980,      0,      0 | 
|  | }; | 
|  |  | 
|  |  | 
|  | /*---------------------------------------------------------------------------*/ | 
|  |  | 
|  | static short capidtmf_recv_window_function[CAPIDTMF_RECV_ACCUMULATE_CYCLES] = | 
|  | { | 
|  | -500L,   -999L,  -1499L,  -1998L,  -2496L,  -2994L,  -3491L,  -3988L, | 
|  | -4483L,  -4978L,  -5471L,  -5963L,  -6454L,  -6943L,  -7431L,  -7917L, | 
|  | -8401L,  -8883L,  -9363L,  -9840L, -10316L, -10789L, -11259L, -11727L, | 
|  | -12193L, -12655L, -13115L, -13571L, -14024L, -14474L, -14921L, -15364L, | 
|  | -15804L, -16240L, -16672L, -17100L, -17524L, -17944L, -18360L, -18772L, | 
|  | -19180L, -19583L, -19981L, -20375L, -20764L, -21148L, -21527L, -21901L, | 
|  | -22270L, -22634L, -22993L, -23346L, -23694L, -24037L, -24374L, -24705L, | 
|  | -25030L, -25350L, -25664L, -25971L, -26273L, -26568L, -26858L, -27141L, | 
|  | -27418L, -27688L, -27952L, -28210L, -28461L, -28705L, -28943L, -29174L, | 
|  | -29398L, -29615L, -29826L, -30029L, -30226L, -30415L, -30598L, -30773L, | 
|  | -30941L, -31102L, -31256L, -31402L, -31541L, -31673L, -31797L, -31914L, | 
|  | -32024L, -32126L, -32221L, -32308L, -32388L, -32460L, -32524L, -32581L, | 
|  | -32631L, -32673L, -32707L, -32734L, -32753L, -32764L, -32768L, -32764L, | 
|  | -32753L, -32734L, -32707L, -32673L, -32631L, -32581L, -32524L, -32460L, | 
|  | -32388L, -32308L, -32221L, -32126L, -32024L, -31914L, -31797L, -31673L, | 
|  | -31541L, -31402L, -31256L, -31102L, -30941L, -30773L, -30598L, -30415L, | 
|  | -30226L, -30029L, -29826L, -29615L, -29398L, -29174L, -28943L, -28705L, | 
|  | -28461L, -28210L, -27952L, -27688L, -27418L, -27141L, -26858L, -26568L, | 
|  | -26273L, -25971L, -25664L, -25350L, -25030L, -24705L, -24374L, -24037L, | 
|  | -23694L, -23346L, -22993L, -22634L, -22270L, -21901L, -21527L, -21148L, | 
|  | -20764L, -20375L, -19981L, -19583L, -19180L, -18772L, -18360L, -17944L, | 
|  | -17524L, -17100L, -16672L, -16240L, -15804L, -15364L, -14921L, -14474L, | 
|  | -14024L, -13571L, -13115L, -12655L, -12193L, -11727L, -11259L, -10789L, | 
|  | -10316L,  -9840L,  -9363L,  -8883L,  -8401L,  -7917L,  -7431L,  -6943L, | 
|  | -6454L,  -5963L,  -5471L,  -4978L,  -4483L,  -3988L,  -3491L,  -2994L, | 
|  | -2496L,  -1998L,  -1499L,   -999L,   -500L, | 
|  | }; | 
|  |  | 
|  | static byte capidtmf_leading_zeroes_table[0x100] = | 
|  | { | 
|  | 8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4, | 
|  | 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, | 
|  | 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, | 
|  | 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, | 
|  | 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, | 
|  | 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, | 
|  | 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, | 
|  | 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, | 
|  | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | 
|  | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | 
|  | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | 
|  | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | 
|  | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | 
|  | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | 
|  | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, | 
|  | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 | 
|  | }; | 
|  |  | 
|  | #define capidtmf_byte_leading_zeroes(b)  (capidtmf_leading_zeroes_table[(BYTE)(b)]) | 
|  | #define capidtmf_word_leading_zeroes(w)  (((w) & 0xff00) ? capidtmf_leading_zeroes_table[(w) >> 8] : 8 + capidtmf_leading_zeroes_table[(w)]) | 
|  | #define capidtmf_dword_leading_zeroes(d)  (((d) & 0xffff0000L) ?    (((d) & 0xff000000L) ? capidtmf_leading_zeroes_table[(d) >> 24] : 8 + capidtmf_leading_zeroes_table[(d) >> 16]) :    (((d) & 0xff00) ? 16 + capidtmf_leading_zeroes_table[(d) >> 8] : 24 + capidtmf_leading_zeroes_table[(d)])) | 
|  |  | 
|  |  | 
|  | /*---------------------------------------------------------------------------*/ | 
|  |  | 
|  |  | 
|  | static void capidtmf_goertzel_loop (long *buffer, long *coeffs, short *sample, long count) | 
|  | { | 
|  | int i, j; | 
|  | long c, d, q0, q1, q2; | 
|  |  | 
|  | for (i = 0; i < CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT - 1; i++) | 
|  | { | 
|  | q1 = buffer[i]; | 
|  | q2 = buffer[i + CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT]; | 
|  | d = coeffs[i] >> 1; | 
|  | c = d << 1; | 
|  | if (c >= 0) | 
|  | { | 
|  | for (j = 0; j < count; j++) | 
|  | { | 
|  | q0 = sample[j] - q2 + (c * (q1 >> 16)) + (((dword)(((dword) d) * ((dword)(q1 & 0xffff)))) >> 15); | 
|  | q2 = q1; | 
|  | q1 = q0; | 
|  | } | 
|  | } | 
|  | else | 
|  | { | 
|  | c = -c; | 
|  | d = -d; | 
|  | for (j = 0; j < count; j++) | 
|  | { | 
|  | q0 = sample[j] - q2 - ((c * (q1 >> 16)) + (((dword)(((dword) d) * ((dword)(q1 & 0xffff)))) >> 15)); | 
|  | q2 = q1; | 
|  | q1 = q0; | 
|  | } | 
|  | } | 
|  | buffer[i] = q1; | 
|  | buffer[i + CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT] = q2; | 
|  | } | 
|  | q1 = buffer[i]; | 
|  | q2 = buffer[i + CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT]; | 
|  | c = (coeffs[i] >> 1) << 1; | 
|  | if (c >= 0) | 
|  | { | 
|  | for (j = 0; j < count; j++) | 
|  | { | 
|  | q0 = sample[j] - q2 + (c * (q1 >> 16)) + (((dword)(((dword)(c >> 1)) * ((dword)(q1 & 0xffff)))) >> 15); | 
|  | q2 = q1; | 
|  | q1 = q0; | 
|  | c -= CAPIDTMF_RECV_FUNDAMENTAL_DECREMENT; | 
|  | } | 
|  | } | 
|  | else | 
|  | { | 
|  | c = -c; | 
|  | for (j = 0; j < count; j++) | 
|  | { | 
|  | q0 = sample[j] - q2 - ((c * (q1 >> 16)) + (((dword)(((dword)(c >> 1)) * ((dword)(q1 & 0xffff)))) >> 15)); | 
|  | q2 = q1; | 
|  | q1 = q0; | 
|  | c += CAPIDTMF_RECV_FUNDAMENTAL_DECREMENT; | 
|  | } | 
|  | } | 
|  | coeffs[i] = c; | 
|  | buffer[i] = q1; | 
|  | buffer[i + CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT] = q2; | 
|  | } | 
|  |  | 
|  |  | 
|  | static void capidtmf_goertzel_result (long *buffer, long *coeffs) | 
|  | { | 
|  | int i; | 
|  | long d, e, q1, q2, lo, mid, hi; | 
|  | dword k; | 
|  |  | 
|  | for (i = 0; i < CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT; i++) | 
|  | { | 
|  | q1 = buffer[i]; | 
|  | q2 = buffer[i + CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT]; | 
|  | d = coeffs[i] >> 1; | 
|  | if (d >= 0) | 
|  | d = ((d << 1) * (-q1 >> 16)) + (((dword)(((dword) d) * ((dword)(-q1 & 0xffff)))) >> 15); | 
|  | else | 
|  | d = ((-d << 1) * (-q1 >> 16)) + (((dword)(((dword) -d) * ((dword)(-q1 & 0xffff)))) >> 15); | 
|  | e = (q2 >= 0) ? q2 : -q2; | 
|  | if (d >= 0) | 
|  | { | 
|  | k = ((dword)(d & 0xffff)) * ((dword)(e & 0xffff)); | 
|  | lo = k & 0xffff; | 
|  | mid = k >> 16; | 
|  | k = ((dword)(d >> 16)) * ((dword)(e & 0xffff)); | 
|  | mid += k & 0xffff; | 
|  | hi = k >> 16; | 
|  | k = ((dword)(d & 0xffff)) * ((dword)(e >> 16)); | 
|  | mid += k & 0xffff; | 
|  | hi += k >> 16; | 
|  | hi += ((dword)(d >> 16)) * ((dword)(e >> 16)); | 
|  | } | 
|  | else | 
|  | { | 
|  | d = -d; | 
|  | k = ((dword)(d & 0xffff)) * ((dword)(e & 0xffff)); | 
|  | lo = -((long)(k & 0xffff)); | 
|  | mid = -((long)(k >> 16)); | 
|  | k = ((dword)(d >> 16)) * ((dword)(e & 0xffff)); | 
|  | mid -= k & 0xffff; | 
|  | hi = -((long)(k >> 16)); | 
|  | k = ((dword)(d & 0xffff)) * ((dword)(e >> 16)); | 
|  | mid -= k & 0xffff; | 
|  | hi -= k >> 16; | 
|  | hi -= ((dword)(d >> 16)) * ((dword)(e >> 16)); | 
|  | } | 
|  | if (q2 < 0) | 
|  | { | 
|  | lo = -lo; | 
|  | mid = -mid; | 
|  | hi = -hi; | 
|  | } | 
|  | d = (q1 >= 0) ? q1 : -q1; | 
|  | k = ((dword)(d & 0xffff)) * ((dword)(d & 0xffff)); | 
|  | lo += k & 0xffff; | 
|  | mid += k >> 16; | 
|  | k = ((dword)(d >> 16)) * ((dword)(d & 0xffff)); | 
|  | mid += (k & 0xffff) << 1; | 
|  | hi += (k >> 16) << 1; | 
|  | hi += ((dword)(d >> 16)) * ((dword)(d >> 16)); | 
|  | d = (q2 >= 0) ? q2 : -q2; | 
|  | k = ((dword)(d & 0xffff)) * ((dword)(d & 0xffff)); | 
|  | lo += k & 0xffff; | 
|  | mid += k >> 16; | 
|  | k = ((dword)(d >> 16)) * ((dword)(d & 0xffff)); | 
|  | mid += (k & 0xffff) << 1; | 
|  | hi += (k >> 16) << 1; | 
|  | hi += ((dword)(d >> 16)) * ((dword)(d >> 16)); | 
|  | mid += lo >> 16; | 
|  | hi += mid >> 16; | 
|  | buffer[i] = (lo & 0xffff) | (mid << 16); | 
|  | buffer[i + CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT] = hi; | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | /*---------------------------------------------------------------------------*/ | 
|  |  | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_697     0 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_770     1 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_852     2 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_941     3 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_1209    4 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_1336    5 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_1477    6 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_1633    7 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_635     8 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_1010    9 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_1140    10 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_1272    11 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_1405    12 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_1555    13 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_1715    14 | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_INDEX_1875    15 | 
|  |  | 
|  | #define CAPIDTMF_RECV_GUARD_SNR_DONTCARE      0xc000 | 
|  | #define CAPIDTMF_RECV_NO_DIGIT                0xff | 
|  | #define CAPIDTMF_RECV_TIME_GRANULARITY        (CAPIDTMF_RECV_ACCUMULATE_CYCLES + 1) | 
|  |  | 
|  | #define CAPIDTMF_RECV_INDICATION_DIGIT        0x0001 | 
|  |  | 
|  | static long capidtmf_recv_goertzel_coef_table[CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT] = | 
|  | { | 
|  | 0xda97L * 2,  /* 697 Hz (Low group 697 Hz) */ | 
|  | 0xd299L * 2,  /* 770 Hz (Low group 770 Hz) */ | 
|  | 0xc8cbL * 2,  /* 852 Hz (Low group 852 Hz) */ | 
|  | 0xbd36L * 2,  /* 941 Hz (Low group 941 Hz) */ | 
|  | 0x9501L * 2,  /* 1209 Hz (High group 1209 Hz) */ | 
|  | 0x7f89L * 2,  /* 1336 Hz (High group 1336 Hz) */ | 
|  | 0x6639L * 2,  /* 1477 Hz (High group 1477 Hz) */ | 
|  | 0x48c6L * 2,  /* 1633 Hz (High group 1633 Hz) */ | 
|  | 0xe14cL * 2,  /* 630 Hz (Lower guard of low group 631 Hz) */ | 
|  | 0xb2e0L * 2,  /* 1015 Hz (Upper guard of low group 1039 Hz) */ | 
|  | 0xa1a0L * 2,  /* 1130 Hz (Lower guard of high group 1140 Hz) */ | 
|  | 0x8a87L * 2,  /* 1272 Hz (Guard between 1209 Hz and 1336 Hz: 1271 Hz) */ | 
|  | 0x7353L * 2,  /* 1405 Hz (2nd harmonics of 697 Hz and guard between 1336 Hz and 1477 Hz: 1405 Hz) */ | 
|  | 0x583bL * 2,  /* 1552 Hz (2nd harmonics of 770 Hz and guard between 1477 Hz and 1633 Hz: 1553 Hz) */ | 
|  | 0x37d8L * 2,  /* 1720 Hz (2nd harmonics of 852 Hz and upper guard of high group: 1715 Hz) */ | 
|  | 0x0000L * 2   /* 100-630 Hz (fundamentals) */ | 
|  | }; | 
|  |  | 
|  |  | 
|  | static word capidtmf_recv_guard_snr_low_table[CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT] = | 
|  | { | 
|  | 14,                                    /* Low group peak versus 697 Hz */ | 
|  | 14,                                    /* Low group peak versus 770 Hz */ | 
|  | 16,                                    /* Low group peak versus 852 Hz */ | 
|  | 16,                                    /* Low group peak versus 941 Hz */ | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* Low group peak versus 1209 Hz */ | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* Low group peak versus 1336 Hz */ | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* Low group peak versus 1477 Hz */ | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* Low group peak versus 1633 Hz */ | 
|  | 14,                                    /* Low group peak versus 635 Hz */ | 
|  | 16,                                    /* Low group peak versus 1010 Hz */ | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* Low group peak versus 1140 Hz */ | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* Low group peak versus 1272 Hz */ | 
|  | DSPDTMF_RX_HARMONICS_SEL_DEFAULT - 8,  /* Low group peak versus 1405 Hz */ | 
|  | DSPDTMF_RX_HARMONICS_SEL_DEFAULT - 4,  /* Low group peak versus 1555 Hz */ | 
|  | DSPDTMF_RX_HARMONICS_SEL_DEFAULT - 4,  /* Low group peak versus 1715 Hz */ | 
|  | 12                                     /* Low group peak versus 100-630 Hz */ | 
|  | }; | 
|  |  | 
|  |  | 
|  | static word capidtmf_recv_guard_snr_high_table[CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT] = | 
|  | { | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* High group peak versus 697 Hz */ | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* High group peak versus 770 Hz */ | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* High group peak versus 852 Hz */ | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* High group peak versus 941 Hz */ | 
|  | 20,                                    /* High group peak versus 1209 Hz */ | 
|  | 20,                                    /* High group peak versus 1336 Hz */ | 
|  | 20,                                    /* High group peak versus 1477 Hz */ | 
|  | 20,                                    /* High group peak versus 1633 Hz */ | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* High group peak versus 635 Hz */ | 
|  | CAPIDTMF_RECV_GUARD_SNR_DONTCARE,      /* High group peak versus 1010 Hz */ | 
|  | 16,                                    /* High group peak versus 1140 Hz */ | 
|  | 4,                                     /* High group peak versus 1272 Hz */ | 
|  | 6,                                     /* High group peak versus 1405 Hz */ | 
|  | 8,                                     /* High group peak versus 1555 Hz */ | 
|  | 16,                                    /* High group peak versus 1715 Hz */ | 
|  | 12                                     /* High group peak versus 100-630 Hz */ | 
|  | }; | 
|  |  | 
|  |  | 
|  | /*---------------------------------------------------------------------------*/ | 
|  |  | 
|  | static void capidtmf_recv_init (t_capidtmf_state   *p_state) | 
|  | { | 
|  | p_state->recv.min_gap_duration = 1; | 
|  | p_state->recv.min_digit_duration = 1; | 
|  |  | 
|  | p_state->recv.cycle_counter = 0; | 
|  | p_state->recv.current_digit_on_time = 0; | 
|  | p_state->recv.current_digit_off_time = 0; | 
|  | p_state->recv.current_digit_value = CAPIDTMF_RECV_NO_DIGIT; | 
|  |  | 
|  | p_state->recv.digit_write_pos = 0; | 
|  | p_state->recv.digit_read_pos = 0; | 
|  | p_state->recv.indication_state = 0; | 
|  | p_state->recv.indication_state_ack = 0; | 
|  | p_state->recv.state = CAPIDTMF_RECV_STATE_IDLE; | 
|  | } | 
|  |  | 
|  |  | 
|  | void capidtmf_recv_enable (t_capidtmf_state   *p_state, word min_digit_duration, word min_gap_duration) | 
|  | { | 
|  | p_state->recv.indication_state_ack &= CAPIDTMF_RECV_INDICATION_DIGIT; | 
|  | p_state->recv.min_digit_duration = (word)(((((dword) min_digit_duration) * 8) + | 
|  | ((dword)(CAPIDTMF_RECV_TIME_GRANULARITY / 2))) / ((dword) CAPIDTMF_RECV_TIME_GRANULARITY)); | 
|  | if (p_state->recv.min_digit_duration <= 1) | 
|  | p_state->recv.min_digit_duration = 1; | 
|  | else | 
|  | (p_state->recv.min_digit_duration)--; | 
|  | p_state->recv.min_gap_duration = | 
|  | (word)((((dword) min_gap_duration) * 8) / ((dword) CAPIDTMF_RECV_TIME_GRANULARITY)); | 
|  | if (p_state->recv.min_gap_duration <= 1) | 
|  | p_state->recv.min_gap_duration = 1; | 
|  | else | 
|  | (p_state->recv.min_gap_duration)--; | 
|  | p_state->recv.state |= CAPIDTMF_RECV_STATE_DTMF_ACTIVE; | 
|  | } | 
|  |  | 
|  |  | 
|  | void capidtmf_recv_disable (t_capidtmf_state   *p_state) | 
|  | { | 
|  | p_state->recv.state &= ~CAPIDTMF_RECV_STATE_DTMF_ACTIVE; | 
|  | if (p_state->recv.state == CAPIDTMF_RECV_STATE_IDLE) | 
|  | capidtmf_recv_init (p_state); | 
|  | else | 
|  | { | 
|  | p_state->recv.cycle_counter = 0; | 
|  | p_state->recv.current_digit_on_time = 0; | 
|  | p_state->recv.current_digit_off_time = 0; | 
|  | p_state->recv.current_digit_value = CAPIDTMF_RECV_NO_DIGIT; | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | word capidtmf_recv_indication (t_capidtmf_state   *p_state, byte *buffer) | 
|  | { | 
|  | word i, j, k, flags; | 
|  |  | 
|  | flags = p_state->recv.indication_state ^ p_state->recv.indication_state_ack; | 
|  | p_state->recv.indication_state_ack ^= flags & CAPIDTMF_RECV_INDICATION_DIGIT; | 
|  | if (p_state->recv.digit_write_pos != p_state->recv.digit_read_pos) | 
|  | { | 
|  | i = 0; | 
|  | k = p_state->recv.digit_write_pos; | 
|  | j = p_state->recv.digit_read_pos; | 
|  | do | 
|  | { | 
|  | buffer[i++] = p_state->recv.digit_buffer[j]; | 
|  | j = (j == CAPIDTMF_RECV_DIGIT_BUFFER_SIZE - 1) ? 0 : j + 1; | 
|  | } while (j != k); | 
|  | p_state->recv.digit_read_pos = k; | 
|  | return (i); | 
|  | } | 
|  | p_state->recv.indication_state_ack ^= flags; | 
|  | return (0); | 
|  | } | 
|  |  | 
|  |  | 
|  | #define CAPIDTMF_RECV_WINDOWED_SAMPLES  32 | 
|  |  | 
|  | void capidtmf_recv_block (t_capidtmf_state   *p_state, byte   *buffer, word length) | 
|  | { | 
|  | byte result_digit; | 
|  | word sample_number, cycle_counter, n, i; | 
|  | word low_peak, high_peak; | 
|  | dword lo, hi; | 
|  | byte   *p; | 
|  | short *q; | 
|  | byte goertzel_result_buffer[CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT]; | 
|  | short windowed_sample_buffer[CAPIDTMF_RECV_WINDOWED_SAMPLES]; | 
|  |  | 
|  |  | 
|  | if (p_state->recv.state & CAPIDTMF_RECV_STATE_DTMF_ACTIVE) | 
|  | { | 
|  | cycle_counter = p_state->recv.cycle_counter; | 
|  | sample_number = 0; | 
|  | while (sample_number < length) | 
|  | { | 
|  | if (cycle_counter < CAPIDTMF_RECV_ACCUMULATE_CYCLES) | 
|  | { | 
|  | if (cycle_counter == 0) | 
|  | { | 
|  | for (i = 0; i < CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT; i++) | 
|  | { | 
|  | p_state->recv.goertzel_buffer[0][i] = 0; | 
|  | p_state->recv.goertzel_buffer[1][i] = 0; | 
|  | } | 
|  | } | 
|  | n = CAPIDTMF_RECV_ACCUMULATE_CYCLES - cycle_counter; | 
|  | if (n > length - sample_number) | 
|  | n = length - sample_number; | 
|  | if (n > CAPIDTMF_RECV_WINDOWED_SAMPLES) | 
|  | n = CAPIDTMF_RECV_WINDOWED_SAMPLES; | 
|  | p = buffer + sample_number; | 
|  | q = capidtmf_recv_window_function + cycle_counter; | 
|  | if (p_state->ulaw) | 
|  | { | 
|  | for (i = 0; i < n; i++) | 
|  | { | 
|  | windowed_sample_buffer[i] = | 
|  | (short)((capidtmf_expand_table_ulaw[p[i]] * ((long)(q[i]))) >> 15); | 
|  | } | 
|  | } | 
|  | else | 
|  | { | 
|  | for (i = 0; i < n; i++) | 
|  | { | 
|  | windowed_sample_buffer[i] = | 
|  | (short)((capidtmf_expand_table_alaw[p[i]] * ((long)(q[i]))) >> 15); | 
|  | } | 
|  | } | 
|  | capidtmf_recv_goertzel_coef_table[CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT - 1] = CAPIDTMF_RECV_FUNDAMENTAL_OFFSET; | 
|  | capidtmf_goertzel_loop (p_state->recv.goertzel_buffer[0], | 
|  | capidtmf_recv_goertzel_coef_table, windowed_sample_buffer, n); | 
|  | cycle_counter += n; | 
|  | sample_number += n; | 
|  | } | 
|  | else | 
|  | { | 
|  | capidtmf_goertzel_result (p_state->recv.goertzel_buffer[0], | 
|  | capidtmf_recv_goertzel_coef_table); | 
|  | for (i = 0; i < CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT; i++) | 
|  | { | 
|  | lo = (dword)(p_state->recv.goertzel_buffer[0][i]); | 
|  | hi = (dword)(p_state->recv.goertzel_buffer[1][i]); | 
|  | if (hi != 0) | 
|  | { | 
|  | n = capidtmf_dword_leading_zeroes (hi); | 
|  | hi = (hi << n) | (lo >> (32 - n)); | 
|  | } | 
|  | else | 
|  | { | 
|  | n = capidtmf_dword_leading_zeroes (lo); | 
|  | hi = lo << n; | 
|  | n += 32; | 
|  | } | 
|  | n = 195 - 3 * n; | 
|  | if (hi >= 0xcb300000L) | 
|  | n += 2; | 
|  | else if (hi >= 0xa1450000L) | 
|  | n++; | 
|  | goertzel_result_buffer[i] = (byte) n; | 
|  | } | 
|  | low_peak = DSPDTMF_RX_SENSITIVITY_LOW_DEFAULT; | 
|  | result_digit = CAPIDTMF_RECV_NO_DIGIT; | 
|  | for (i = 0; i < CAPIDTMF_LOW_GROUP_FREQUENCIES; i++) | 
|  | { | 
|  | if (goertzel_result_buffer[i] > low_peak) | 
|  | { | 
|  | low_peak = goertzel_result_buffer[i]; | 
|  | result_digit = (byte) i; | 
|  | } | 
|  | } | 
|  | high_peak = DSPDTMF_RX_SENSITIVITY_HIGH_DEFAULT; | 
|  | n = CAPIDTMF_RECV_NO_DIGIT; | 
|  | for (i = CAPIDTMF_LOW_GROUP_FREQUENCIES; i < CAPIDTMF_RECV_BASE_FREQUENCY_COUNT; i++) | 
|  | { | 
|  | if (goertzel_result_buffer[i] > high_peak) | 
|  | { | 
|  | high_peak = goertzel_result_buffer[i]; | 
|  | n = (i - CAPIDTMF_LOW_GROUP_FREQUENCIES) << 2; | 
|  | } | 
|  | } | 
|  | result_digit |= (byte) n; | 
|  | if (low_peak + DSPDTMF_RX_HIGH_EXCEEDING_LOW_DEFAULT < high_peak) | 
|  | result_digit = CAPIDTMF_RECV_NO_DIGIT; | 
|  | if (high_peak + DSPDTMF_RX_LOW_EXCEEDING_HIGH_DEFAULT < low_peak) | 
|  | result_digit = CAPIDTMF_RECV_NO_DIGIT; | 
|  | n = 0; | 
|  | for (i = 0; i < CAPIDTMF_RECV_TOTAL_FREQUENCY_COUNT; i++) | 
|  | { | 
|  | if ((((short)(low_peak - goertzel_result_buffer[i] - capidtmf_recv_guard_snr_low_table[i])) < 0) | 
|  | || (((short)(high_peak - goertzel_result_buffer[i] - capidtmf_recv_guard_snr_high_table[i])) < 0)) | 
|  | { | 
|  | n++; | 
|  | } | 
|  | } | 
|  | if (n != 2) | 
|  | result_digit = CAPIDTMF_RECV_NO_DIGIT; | 
|  |  | 
|  | if (result_digit == CAPIDTMF_RECV_NO_DIGIT) | 
|  | { | 
|  | if (p_state->recv.current_digit_on_time != 0) | 
|  | { | 
|  | if (++(p_state->recv.current_digit_off_time) >= p_state->recv.min_gap_duration) | 
|  | { | 
|  | p_state->recv.current_digit_on_time = 0; | 
|  | p_state->recv.current_digit_off_time = 0; | 
|  | } | 
|  | } | 
|  | else | 
|  | { | 
|  | if (p_state->recv.current_digit_off_time != 0) | 
|  | (p_state->recv.current_digit_off_time)--; | 
|  | } | 
|  | } | 
|  | else | 
|  | { | 
|  | if ((p_state->recv.current_digit_on_time == 0) | 
|  | && (p_state->recv.current_digit_off_time != 0)) | 
|  | { | 
|  | (p_state->recv.current_digit_off_time)--; | 
|  | } | 
|  | else | 
|  | { | 
|  | n = p_state->recv.current_digit_off_time; | 
|  | if ((p_state->recv.current_digit_on_time != 0) | 
|  | && (result_digit != p_state->recv.current_digit_value)) | 
|  | { | 
|  | p_state->recv.current_digit_on_time = 0; | 
|  | n = 0; | 
|  | } | 
|  | p_state->recv.current_digit_value = result_digit; | 
|  | p_state->recv.current_digit_off_time = 0; | 
|  | if (p_state->recv.current_digit_on_time != 0xffff) | 
|  | { | 
|  | p_state->recv.current_digit_on_time += n + 1; | 
|  | if (p_state->recv.current_digit_on_time >= p_state->recv.min_digit_duration) | 
|  | { | 
|  | p_state->recv.current_digit_on_time = 0xffff; | 
|  | i = (p_state->recv.digit_write_pos == CAPIDTMF_RECV_DIGIT_BUFFER_SIZE - 1) ? | 
|  | 0 : p_state->recv.digit_write_pos + 1; | 
|  | if (i == p_state->recv.digit_read_pos) | 
|  | { | 
|  | trace (dprintf ("%s,%d: Receive digit overrun", | 
|  | (char   *)(FILE_), __LINE__)); | 
|  | } | 
|  | else | 
|  | { | 
|  | p_state->recv.digit_buffer[p_state->recv.digit_write_pos] = result_digit; | 
|  | p_state->recv.digit_write_pos = i; | 
|  | p_state->recv.indication_state = | 
|  | (p_state->recv.indication_state & ~CAPIDTMF_RECV_INDICATION_DIGIT) | | 
|  | (~p_state->recv.indication_state_ack & CAPIDTMF_RECV_INDICATION_DIGIT); | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  | cycle_counter = 0; | 
|  | sample_number++; | 
|  | } | 
|  | } | 
|  | p_state->recv.cycle_counter = cycle_counter; | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void capidtmf_init (t_capidtmf_state   *p_state, byte ulaw) | 
|  | { | 
|  | p_state->ulaw = ulaw; | 
|  | capidtmf_recv_init (p_state); | 
|  | } | 
|  |  | 
|  |  | 
|  | /*---------------------------------------------------------------------------*/ |