Optionally build integer-based routines for FSK tone decoding (but default
authorTilghman Lesher <tilghman@meg.abyt.es>
Mon, 21 Jul 2008 20:59:03 +0000 (20:59 +0000)
committerTilghman Lesher <tilghman@meg.abyt.es>
Mon, 21 Jul 2008 20:59:03 +0000 (20:59 +0000)
to the more accurate float-based routines).
(Closes issue #11679)
(Step 1 of 2)

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@132510 65c4cc65-6c06-0410-ace0-fbb531ad65f3

build_tools/cflags.xml
include/asterisk/fskmodem_float.h [new file with mode: 0644]
include/asterisk/fskmodem_int.h [moved from include/asterisk/fskmodem.h with 100% similarity]
main/callerid.c
main/fskmodem_float.c [new file with mode: 0644]
main/fskmodem_int.c [moved from main/fskmodem.c with 100% similarity]
main/tdd.c

index 21f9abc..fc20f21 100644 (file)
@@ -44,4 +44,6 @@
                </member>
                <member name="IAX_OLD_FIND" displayname="Use the old, slow method of searching for IAX callnos">
                </member>
+               <member name="INTEGER_CALLERID" displayname="Use the (less accurate) integer-based method for decoding FSK tones (for embedded systems)">
+               </member>
        </category>
diff --git a/include/asterisk/fskmodem_float.h b/include/asterisk/fskmodem_float.h
new file mode 100644 (file)
index 0000000..3b350fb
--- /dev/null
@@ -0,0 +1,71 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 1999 - 2005, Digium, Inc.
+ *
+ * Mark Spencer <markster@digium.com>
+ *
+ * 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 Modem Support
+ * \note Includes code and algorithms from the Zapata library.
+ */
+
+#ifndef _ASTERISK_FSKMODEM_H
+#define _ASTERISK_FSKMODEM_H
+
+#define PARITY_NONE            0
+#define PARITY_EVEN            1
+#define PARITY_ODD             2
+
+
+#define NCOLA 0x4000
+
+typedef struct {
+       float spb;      /*!< Samples / Bit */
+       int nbit;       /*!< Number of Data Bits (5,7,8) */
+       float nstop;    /*!< Number of Stop Bits 1,1.5,2  */
+       int parity;     /*!< Parity 0=none 1=even 2=odd */
+       int hdlc;       /*!< Modo Packet */
+       float x0;
+       float x1;
+       float x2;
+       float cont;
+       int bw;                         /*!< Bandwidth */
+       double fmxv[8],fmyv[8];         /*!< filter stuff for M filter */
+       int     fmp;                    /*!< pointer for M filter */
+       double fsxv[8],fsyv[8];         /*!< filter stuff for S filter */
+       int     fsp;                    /*!< pointer for S filter */
+       double flxv[8],flyv[8];         /*!< filter stuff for L filter */
+       int     flp;                    /*!< pointer for L filter */
+       int f_mark_idx;                 /*!< Mark frequency index (f_M-500)/5 */
+       int f_space_idx;                /*!< Space frequency index (f_S-500)/5 */
+       int state;
+       int pcola;                      /*!< Pointer to data queues */
+       float cola_in[NCOLA];           /*!< Queue of input samples */
+       float cola_filter[NCOLA];       /*!< Queue of samples after filters */
+       float cola_demod[NCOLA];        /*!< Queue of demodulated samples */
+} fsk_data;
+
+/* \brief Retrieve a serial byte into outbyte.
+   Buffer is a pointer into a series of
+   shorts and len records the number of bytes in the buffer.  len will be
+   overwritten with the number of bytes left that were not consumed.
+   \return return value is as follows:
+   \arg 0: Still looking for something...
+   \arg 1: An output byte was received and stored in outbyte
+   \arg -1: An error occured in the transmission
+   He must be called with at least 80 bytes of buffer. */
+int fsk_serial(fsk_data *fskd, short *buffer, int *len, int *outbyte);
+
+#endif /* _ASTERISK_FSKMODEM_H */
index c8c3afc..1d5ae04 100644 (file)
@@ -128,6 +128,7 @@ struct callerid_state *callerid_new(int cid_signalling)
        struct callerid_state *cid;
 
        if ((cid = ast_calloc(1, sizeof(*cid)))) {
+#ifdef INTEGER_CALLERID
                cid->fskd.ispb = 7;             /* 1200 baud */ 
                /* Set up for 1200 / 8000 freq *32 to allow ints */
                cid->fskd.pllispb  = (int)(8000 * 32  / 1200);
@@ -155,6 +156,27 @@ struct callerid_state *callerid_new(int cid_signalling)
                /* cid->pos = 0; */
 
                fskmodem_init(&cid->fskd);
+#else
+               cid->fskd.spb = 7.0;            /* 1200 baud */
+               /* cid->fskd.hdlc = 0; */       /* Async */
+               cid->fskd.nbit = 8;             /* 8 bits */
+               cid->fskd.nstop = 1.0;          /* 1 stop bit */
+               /* cid->fskd.paridad = 0; */    /* No parity */
+               cid->fskd.bw = 1;               /* Filter 800 Hz */
+               if (cid_signalling == 2) {      /* v23 signalling */
+                       cid->fskd.f_mark_idx =  4;      /* 1300 Hz */
+                       cid->fskd.f_space_idx = 5;      /* 2100 Hz */
+               } else {                        /* Bell 202 signalling as default */
+                       cid->fskd.f_mark_idx =  2;      /* 1200 Hz */
+                       cid->fskd.f_space_idx = 3;      /* 2200 Hz */
+               }
+               /* cid->fskd.pcola = 0; */      /* No clue */
+               /* cid->fskd.cont = 0.0; */     /* Digital PLL reset */
+               /* cid->fskd.x0 = 0.0; */
+               /* cid->fskd.state = 0; */
+               cid->flags = CID_UNKNOWN_NAME | CID_UNKNOWN_NUMBER;
+               /* cid->pos = 0; */
+#endif
        }
 
        return cid;
diff --git a/main/fskmodem_float.c b/main/fskmodem_float.c
new file mode 100644 (file)
index 0000000..f773009
--- /dev/null
@@ -0,0 +1,360 @@
+/*
+ * 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 <stdio.h>
+
+#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 float get_sample(short **buffer, int *len)
+{
+       float retval;
+       retval = (float) **buffer / 256;
+       (*buffer)++;
+       (*len)--;
+       return retval;
+};
+
+#define GET_SAMPLE get_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, }, 
+};
+
+
+/*! Band-pass filter for MARK frequency */
+static inline float filterM(fsk_data *fskd,float in)
+{
+       int i, j;
+       double s;
+       double *pc;
+       
+       pc = &coef_in[fskd->f_mark_idx][fskd->bw][0];
+       fskd->fmxv[(fskd->fmp+6)&7] = in*(*pc++);
+       
+       s = (fskd->fmxv[(fskd->fmp + 6) & 7] - fskd->fmxv[fskd->fmp]) + 3 * (fskd->fmxv[(fskd->fmp + 2) & 7] - fskd->fmxv[(fskd->fmp + 4) & 7]);
+       for (i = 0, j = fskd->fmp; i < 6; i++, j++) 
+               s += fskd->fmyv[j&7]*(*pc++);
+       fskd->fmyv[j&7] = s;
+       fskd->fmp++;
+       fskd->fmp &= 7;
+       return s;
+}
+
+/*! Band-pass filter for SPACE frequency */
+static inline float filterS(fsk_data *fskd,float in)
+{
+       int i, j;
+       double s;
+       double *pc;
+       
+       pc = &coef_in[fskd->f_space_idx][fskd->bw][0];
+       fskd->fsxv[(fskd->fsp+6)&7] = in*(*pc++);
+       
+       s = (fskd->fsxv[(fskd->fsp + 6) & 7] - fskd->fsxv[fskd->fsp]) + 3 * (fskd->fsxv[(fskd->fsp + 2) & 7] - fskd->fsxv[(fskd->fsp + 4) & 7]);
+       for (i = 0, j = fskd->fsp; i < 6; i++, j++) 
+               s += fskd->fsyv[j&7]*(*pc++);
+       fskd->fsyv[j&7] = s;
+       fskd->fsp++;
+       fskd->fsp &= 7;
+       return s;
+}
+
+/*! Low-pass filter for demodulated data */
+static inline float filterL(fsk_data *fskd,float in)
+{
+       int i, j;
+       double s;
+       double *pc;
+       
+       pc = &coef_out[fskd->bw][0];
+       fskd->flxv[(fskd->flp + 6) & 7] = in * (*pc++); 
+       
+       s = (fskd->flxv[fskd->flp] + fskd->flxv[(fskd->flp+6)&7]) +
+         6  * (fskd->flxv[(fskd->flp+1)&7] + fskd->flxv[(fskd->flp+5)&7]) +
+         15 * (fskd->flxv[(fskd->flp+2)&7] + fskd->flxv[(fskd->flp+4)&7]) +
+         20 *  fskd->flxv[(fskd->flp+3)&7]; 
+       
+       for (i = 0,j = fskd->flp;i<6;i++,j++)
+               s += fskd->flyv[j&7]*(*pc++);
+       fskd->flyv[j&7] = s;
+       fskd->flp++;
+       fskd->flp &= 7;
+       return s;
+}
+
+static inline int demodulator(fsk_data *fskd, float *retval, float x)
+{
+       float xS,xM;
+
+       fskd->cola_in[fskd->pcola] = x;
+       
+       xS = filterS(fskd,x);
+       xM = filterM(fskd,x);
+
+       fskd->cola_filter[fskd->pcola] = xM-xS;
+
+       x = filterL(fskd,xM*xM - xS*xS);
+       
+       fskd->cola_demod[fskd->pcola++] = x;
+       fskd->pcola &=  (NCOLA-1);
+
+       *retval = x;
+       return 0;
+}
+
+static int get_bit_raw(fsk_data *fskd, short *buffer, int *len)
+{
+       /* This function implements a DPLL to synchronize with the bits */
+       float x,spb,spb2,ds;
+       int f;
+
+       spb = fskd->spb; 
+       if (fskd->spb == 7)
+               spb = 8000.0 / 1200.0;
+       ds = spb/32.;
+       spb2 = spb/2.;
+
+       for (f = 0;;) {
+               if (demodulator(fskd, &x, GET_SAMPLE))
+                       return -1;
+               if ((x * fskd->x0) < 0) {       /* Transition */
+                       if (!f) {
+                               if (fskd->cont<(spb2))
+                                       fskd->cont += ds;
+                               else
+                                       fskd->cont -= ds;
+                               f = 1;
+                       }
+               }
+               fskd->x0 = x;
+               fskd->cont += 1.;
+               if (fskd->cont > spb) {
+                       fskd->cont -= spb;
+                       break;
+               }
+       }
+       f = (x > 0) ? 0x80 : 0;
+       return f;
+}
+
+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 */
+               /*
+               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 (demodulator(fskd, &fskd->x1, GET_SAMPLE))
+                       return -1;
+               samples++;
+               for (;;) {
+search_startbit2:                 
+                       if (*len <= 0) {
+                               fskd->state  =  STATE_SEARCH_STARTBIT2;
+                               return 0;
+                       }
+                       samples++;
+                       if (demodulator(fskd, &fskd->x2, GET_SAMPLE))
+                               return(-1);
+#if 0
+                       printf("x2  =  %5.5f ", fskd->x2);
+#endif                 
+                       if (fskd->x2 < -0.5)
+                               break; 
+               }
+search_startbit3:                 
+               /* We await for 0.5 bits before using DPLL */
+               i = fskd->spb/2;
+               if (*len < i) {
+                       fskd->state = STATE_SEARCH_STARTBIT3;
+                       return 0;
+               }
+               for (; i>0; i--) {
+                       if (demodulator(fskd, &fskd->x1, GET_SAMPLE))
+                               return(-1); 
+#if 0
+                       printf("x1 = %5.5f ", fskd->x1);
+#endif                 
+                       samples++;
+               }
+
+               /* x1 must be negative (start bit confirmation) */
+
+       } while (fskd->x1 > 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->nstop;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;
+}
similarity index 100%
rename from main/fskmodem.c
rename to main/fskmodem_int.c
index e07d5b0..8cbe188 100644 (file)
@@ -99,6 +99,7 @@ struct tdd_state *tdd_new(void)
        struct tdd_state *tdd;
        tdd = calloc(1, sizeof(*tdd));
        if (tdd) {
+#ifdef INTEGER_CALLERID
                tdd->fskd.ispb = 176;        /* 45.5 baud */
                /* Set up for 45.5 / 8000 freq *32 to allow ints */
                tdd->fskd.pllispb  = (int)((8000 * 32 * 2) / 90);
@@ -115,8 +116,24 @@ struct tdd_state *tdd_new(void)
                tdd->fskd.state = 0;
                tdd->pos = 0;
                tdd->mode = 0;
-               tdd->charnum = 0;
                fskmodem_init(&tdd->fskd);
+#else
+               tdd->fskd.spb = 176;        /* 45.5 baud */
+               tdd->fskd.hdlc = 0;         /* Async */
+               tdd->fskd.nbit = 5;         /* 5 bits */
+               tdd->fskd.nstop = 1.5;      /* 1.5 stop bits */
+               tdd->fskd.parity = 0;       /* No parity */
+               tdd->fskd.bw=0;             /* Filter 75 Hz */
+               tdd->fskd.f_mark_idx = 0;   /* 1400 Hz */
+               tdd->fskd.f_space_idx = 1;  /* 1800 Hz */
+               tdd->fskd.pcola = 0;        /* No clue */
+               tdd->fskd.cont = 0;         /* Digital PLL reset */
+               tdd->fskd.x0 = 0.0;
+               tdd->fskd.state = 0;
+               tdd->pos = 0;
+               tdd->mode = 2;
+#endif
+               tdd->charnum = 0;
        } else
                ast_log(LOG_WARNING, "Out of memory\n");
        return tdd;