diff options
author | tilghman <tilghman@f38db490-d61c-443f-a65b-d21fe96a405b> | 2008-07-21 21:02:25 +0000 |
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committer | tilghman <tilghman@f38db490-d61c-443f-a65b-d21fe96a405b> | 2008-07-21 21:02:25 +0000 |
commit | 270a084091952b3d63d198e334cfaca8f947fe55 (patch) | |
tree | 13ccddd05502830068366280a71872a7cb9e434f /main/fskmodem.c | |
parent | caafb40114bc5226084f2e20e239d0201ae7c007 (diff) |
Merged revisions 132510 via svnmerge from
https://origsvn.digium.com/svn/asterisk/trunk
........
r132510 | tilghman | 2008-07-21 15:59:03 -0500 (Mon, 21 Jul 2008) | 5 lines
Optionally build integer-based routines for FSK tone decoding (but default
to the more accurate float-based routines).
(Closes issue #11679)
(Step 1 of 2)
........
git-svn-id: http://svn.digium.com/svn/asterisk/branches/1.6.0@132512 f38db490-d61c-443f-a65b-d21fe96a405b
Diffstat (limited to 'main/fskmodem.c')
-rw-r--r-- | main/fskmodem.c | 363 |
1 files changed, 0 insertions, 363 deletions
diff --git a/main/fskmodem.c b/main/fskmodem.c deleted file mode 100644 index 8f84f5800..000000000 --- a/main/fskmodem.c +++ /dev/null @@ -1,363 +0,0 @@ -/* - * Asterisk -- An open source telephony toolkit. - * - * Copyright (C) 1999 - 2005, Digium, Inc. - * - * Mark Spencer <markster@digium.com> - * - * Includes code and algorithms from the Zapata library. - * - * See http://www.asterisk.org for more information about - * the Asterisk project. Please do not directly contact - * any of the maintainers of this project for assistance; - * the project provides a web site, mailing lists and IRC - * channels for your use. - * - * This program is free software, distributed under the terms of - * the GNU General Public License Version 2. See the LICENSE file - * at the top of the source tree. - */ - -/*! \file - * - * \brief FSK Modulator/Demodulator - * - * \author Mark Spencer <markster@digium.com> - * - * \arg Includes code and algorithms from the Zapata library. - * - */ - -#include "asterisk.h" - -ASTERISK_FILE_VERSION(__FILE__, "$Revision$") - -#include "asterisk/fskmodem.h" - -#define NBW 2 -#define BWLIST {75,800} -#define NF 6 -#define FLIST {1400,1800,1200,2200,1300,2100} - -#define STATE_SEARCH_STARTBIT 0 -#define STATE_SEARCH_STARTBIT2 1 -#define STATE_SEARCH_STARTBIT3 2 -#define STATE_GET_BYTE 3 - -static inline int iget_sample(short **buffer, int *len) -{ - int retval; - retval = (int) **buffer; - (*buffer)++; - (*len)--; - return retval; -} - -#define IGET_SAMPLE iget_sample(&buffer, len) -/*! \brief Coefficients for input filters - * Coefficients table, generated by program "mkfilter" - * mkfilter is part of the zapatatelephony.org distribution - * Format: coef[IDX_FREC][IDX_BW][IDX_COEF] - * IDX_COEF = 0 => 1/GAIN - * IDX_COEF = 1-6 => Coefficientes y[n] -*/ -static double coef_in[NF][NBW][8]={ - { { 1.8229206611e-04,-7.8997325866e-01,2.2401819940e+00,-4.6751353581e+00,5.5080745712e+00,-5.0571565772e+00,2.6215820004e+00,0.0000000000e+00, - }, { 9.8532175289e-02,-5.6297236492e-02,3.3146713415e-01,-9.2239200436e-01,1.4844365184e+00,-2.0183258642e+00,2.0074154497e+00,0.0000000000e+00, - }, }, { { 1.8229206610e-04,-7.8997325866e-01,7.7191410839e-01,-2.8075643964e+00,1.6948618347e+00,-3.0367273700e+00,9.0333559408e-01,0.0000000000e+00, - }, { 9.8531161839e-02,-5.6297236492e-02,1.1421579050e-01,-4.8122536483e-01,4.0121072432e-01,-7.4834487567e-01,6.9170822332e-01,0.0000000000e+00, - }, }, { { 1.8229206611e-04,-7.8997325866e-01,2.9003821430e+00,-6.1082779024e+00,7.7169345751e+00,-6.6075999680e+00,3.3941838836e+00,0.0000000000e+00, - }, { 9.8539686961e-02,-5.6297236492e-02,4.2915323820e-01,-1.2609358633e+00,2.2399213250e+00,-2.9928879142e+00,2.5990173742e+00,0.0000000000e+00, - }, }, { { 1.8229206610e-04,-7.8997325866e-01,-7.7191410839e-01,-2.8075643964e+00,-1.6948618347e+00,-3.0367273700e+00,-9.0333559408e-01,0.0000000000e+00, - }, { 9.8531161839e-02,-5.6297236492e-02,-1.1421579050e-01,-4.8122536483e-01,-4.0121072432e-01,-7.4834487567e-01,-6.9170822332e-01,0.0000000000e+00, - }, }, { { 1.8229206611e-04,-7.8997325866e-01,2.5782298908e+00,-5.3629717478e+00,6.5890882172e+00,-5.8012914776e+00,3.0171839130e+00,0.0000000000e+00, - }, { 9.8534230718e-02,-5.6297236492e-02,3.8148618075e-01,-1.0848760410e+00,1.8441165168e+00,-2.4860666655e+00,2.3103384142e+00,0.0000000000e+00, - }, }, { { 1.8229206610e-04,-7.8997325866e-01,-3.8715051001e-01,-2.6192408538e+00,-8.3977994034e-01,-2.8329897913e+00,-4.5306444352e-01,0.0000000000e+00, - }, { 9.8531160936e-02,-5.6297236492e-02,-5.7284484199e-02,-4.3673866734e-01,-1.9564766257e-01,-6.2028156584e-01,-3.4692356122e-01,0.0000000000e+00, - }, }, -}; - -/*! \brief Coefficients for output filter - * Coefficients table, generated by program "mkfilter" - * Format: coef[IDX_BW][IDX_COEF] - * IDX_COEF = 0 => 1/GAIN - * IDX_COEF = 1-6 => Coefficientes y[n] -*/ -static double coef_out[NBW][8]={ - { 1.3868644653e-08,-6.3283665042e-01,4.0895057217e+00,-1.1020074592e+01,1.5850766191e+01,-1.2835109292e+01,5.5477477340e+00,0.0000000000e+00, - }, { 3.1262119724e-03,-7.8390522307e-03,8.5209627801e-02,-4.0804129163e-01,1.1157139955e+00,-1.8767603680e+00,1.8916395224e+00,0.0000000000e+00 - }, -}; - -/*! Integer Pass Band demodulator filter */ -static inline int ibpdfilter(struct filter_struct * fs, int in) -{ - int i,j; - int s; - int64_t s_interim; - - /* integer filter */ - s = in * fs->icoefs[0]; - fs->ixv[(fs->ip + 6) & 7] = s; - - s = (fs->ixv[fs->ip] + fs->ixv[(fs->ip + 6) & 7]) + - 6 * (fs->ixv[(fs->ip + 1) & 7] + fs->ixv[(fs->ip + 5) & 7]) + - 15 * (fs->ixv[(fs->ip + 2) & 7] + fs->ixv[(fs->ip + 4) & 7]) + - 20 * fs->ixv[(fs->ip + 3) & 7]; - - for (i = 1, j = fs->ip; i < 7; i++, j++) { - /* Promote operation to 64 bit to prevent overflow that occurred in 32 bit) */ - s_interim = (int64_t)(fs->iyv[j & 7]) * - (int64_t)(fs->icoefs[i]) / - (int64_t)(1024); - s += (int) s_interim; - } - fs->iyv[j & 7] = s; - fs->ip++; - fs->ip &= 7; - return s; -} - -/*! Integer Band Pass filter */ -static inline int ibpfilter(struct filter_struct * fs, int in) -{ - int i, j; - int s; - int64_t s_interim; - - /* integer filter */ - s = in * fs->icoefs[0] / 256; - fs->ixv[(fs->ip + 6) & 7] = s; - - s = (fs->ixv[(fs->ip + 6) & 7] - fs->ixv[fs->ip]) - + 3 * (fs->ixv[(fs->ip + 2) & 7] - fs->ixv[(fs->ip + 4) & 7]); - - for (i = 1, j = fs->ip; i < 7; i++, j++) { - s_interim = (int64_t)(fs->iyv[j & 7]) * - (int64_t)(fs->icoefs[i]) / - (int64_t)(256); - s += (int) s_interim; - } - fs->iyv[j & 7] = s; - fs->ip++; - fs->ip &= 7; - return s; -} - -static inline int idemodulator(fsk_data *fskd, int *retval, int x) -{ - int is, im, id; - int ilin2; - - is = ibpfilter(&fskd->space_filter, x); - im = ibpfilter(&fskd->mark_filter, x); - - ilin2 = ((im * im) - (is * is)) / (256 * 256); - - id = ibpdfilter(&fskd->demod_filter, ilin2); - - *retval = id; - return 0; -} - -static int get_bit_raw(fsk_data *fskd, short *buffer, int *len) -{ - /* This function implements a DPLL to synchronize with the bits */ - int f; - - int ix; - /* PLL coeffs are set up in callerid_new */ - for (f = 0;;) { - if (idemodulator(fskd, &ix, IGET_SAMPLE)) return(-1); - if ((ix * fskd->xi0) < 0) { /* Transicion */ - if (!f) { - if (fskd->icont < (fskd->pllispb2)) { - fskd->icont += fskd->pllids; - } else { - fskd->icont -= fskd->pllids; - } - f = 1; - } - } - fskd->xi0 = ix; - fskd->icont += 32; - if (fskd->icont > fskd->pllispb) { - fskd->icont -= fskd->pllispb; - break; - } - } - f = (ix > 0) ? 0x80 : 0; - return f; -} - -int fskmodem_init(fsk_data *fskd) -{ - int i; - - fskd->space_filter.ip = 0; - fskd->mark_filter.ip = 0; - fskd->demod_filter.ip = 0; - - for ( i = 0 ; i < 7 ; i++ ) { - fskd->space_filter.icoefs[i] = - coef_in[fskd->f_space_idx][fskd->bw][i] * 256; - fskd->space_filter.ixv[i] = 0;; - fskd->space_filter.iyv[i] = 0;; - - fskd->mark_filter.icoefs[i] = - coef_in[fskd->f_mark_idx][fskd->bw][i] * 256; - fskd->mark_filter.ixv[i] = 0;; - fskd->mark_filter.iyv[i] = 0;; - - fskd->demod_filter.icoefs[i] = - coef_out[fskd->bw][i] * 1024; - fskd->demod_filter.ixv[i] = 0;; - fskd->demod_filter.iyv[i] = 0;; - } - return 0; -} - -int fsk_serial(fsk_data *fskd, short *buffer, int *len, int *outbyte) -{ - int a; - int i, j, n1, r; - int samples = 0; - int olen; - int beginlen = *len; - int beginlenx; - - switch (fskd->state) { - /* Pick up where we left off */ - case STATE_SEARCH_STARTBIT2: - goto search_startbit2; - case STATE_SEARCH_STARTBIT3: - goto search_startbit3; - case STATE_GET_BYTE: - goto getbyte; - } - /* We await for start bit */ - do { - /* this was jesus's nice, reasonable, working (at least with RTTY) code - to look for the beginning of the start bit. Unfortunately, since TTY/TDD's - just start sending a start bit with nothing preceding it at the beginning - of a transmission (what a LOSING design), we cant do it this elegantly */ - /* NOT USED - if (demodulator(zap,&x1)) - return -1; - for(;;) { - if (demodulator(zap,&x2)) - return -1; - if (x1>0 && x2<0) break; - x1=x2; - } - */ - /* this is now the imprecise, losing, but functional code to detect the - beginning of a start bit in the TDD sceanario. It just looks for sufficient - level to maybe, perhaps, guess, maybe that its maybe the beginning of - a start bit, perhaps. This whole thing stinks! */ - beginlenx = beginlen; /* just to avoid unused war warnings */ - if (idemodulator(fskd, &fskd->xi1, IGET_SAMPLE)) - return -1; - samples++; - for(;;) { -search_startbit2: - if (*len <= 0) { - fskd->state = STATE_SEARCH_STARTBIT2; - return 0; - } - samples++; - if (idemodulator(fskd, &fskd->xi2, IGET_SAMPLE)) - return -1; -#if 0 - printf("xi2 = %d ", fskd->xi2); -#endif - if (fskd->xi2 < 512) { - break; - } - } -search_startbit3: - /* We await for 0.5 bits before using DPLL */ - i = fskd->ispb / 2; - if (*len < i) { - fskd->state = STATE_SEARCH_STARTBIT3; - return 0; - } - for (; i > 0; i--) { - if (idemodulator(fskd, &fskd->xi1, IGET_SAMPLE)) - return(-1); -#if 0 - printf("xi1 = %d ", fskd->xi1); -#endif - samples++; - } - - /* x1 must be negative (start bit confirmation) */ - - } while (fskd->xi1 > 0); - fskd->state = STATE_GET_BYTE; - -getbyte: - - /* Need at least 80 samples (for 1200) or - 1320 (for 45.5) to be sure we'll have a byte */ - if (fskd->nbit < 8) { - if (*len < 1320) - return 0; - } else { - if (*len < 80) - return 0; - } - - /* Now we read the data bits */ - j = fskd->nbit; - for (a = n1 = 0; j; j--) { - olen = *len; - i = get_bit_raw(fskd, buffer, len); - buffer += (olen - *len); - if (i == -1) - return -1; - if (i) - n1++; - a >>= 1; - a |= i; - } - j = 8 - fskd->nbit; - a >>= j; - - /* We read parity bit (if exists) and check parity */ - if (fskd->parity) { - olen = *len; - i = get_bit_raw(fskd, buffer, len); - buffer += (olen - *len); - if (i == -1) - return -1; - if (i) - n1++; - if (fskd->parity == 1) { /* parity=1 (even) */ - if (n1 & 1) - a |= 0x100; /* error */ - } else { /* parity=2 (odd) */ - if (!(n1 & 1)) - a |= 0x100; /* error */ - } - } - - /* We read STOP bits. All of them must be 1 */ - - for (j = fskd->instop; j; j--) { - r = get_bit_raw(fskd, buffer, len); - if (r == -1) - return -1; - if (!r) - a |= 0x200; - } - - /* And finally we return - * Bit 8 : Parity error - * Bit 9 : Framming error - */ - - *outbyte = a; - fskd->state = STATE_SEARCH_STARTBIT; - return 1; -} |