/* * 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); } /*---------------------------------------------------------------------------*/