FreeCalypso > hg > freecalypso-tools

annotate miscutil/fc-tch2fr.c @ 597:ca4433b714d2

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CHANGES: fc-fsio cleaning commands documented
author Mychaela Falconia <falcon@freecalypso.org>
date Tue, 04 Feb 2020 18:22:22 +0000
parents d57f68d0568d
children
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6
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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1 /*
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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2 * Our experimental Calypso firmware enables us to capture the output of
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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3 * the GSM 05.03 channel decoder in the DSP, i.e., the bits leaving the
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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4 * channel decoder and going into the speech decoder. Our fc-shell utility
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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5 * allows saving this capture to a file; the captured booty includes not only
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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6 * the expected 260 bits per frame, but also some DSP status words which are
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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7 * not fully understood, but which are believed to contain indications as to
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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8 * whether the decoded speech frame is good or bad.
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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9 *
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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10 * My first naive thought was to save the captured speech frames in libgsm
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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11 * format so I could then play them with the 'play' command (SoX package)
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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12 * under Linux, but the problem with this naive approach is that the bad frames
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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13 * indication is lost, and some of the saved "speech" frames will contain
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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14 * utter garbage, resulting in very unkind-on-ears noises if that file is
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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15 * then played. I don't know what the proper solution should be; I don't know
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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16 * what the commercial cellphone implementations of the GSM 06.10 speech decoder
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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17 * (buried in black box DSPs) do when they get bad frames from the channel
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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18 * decoder.
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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19 *
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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20 * The present utility reproduces the naive behaviour of my previous
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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21 * implementation of fc-shell's tch record command: it takes hex files written
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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22 * by the current implementation of tch record in fc-shell, DISREGARDS the
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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23 * DSP status words, and blindly converts each 260-bit frame (good or bad)
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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24 * into libgsm format.
d57f68d0568d fc-tch2fr utility written, added under miscutil
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25 */
d57f68d0568d fc-tch2fr utility written, added under miscutil
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26
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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27 #include <sys/types.h>
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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28 #include <ctype.h>
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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29 #include <stdio.h>
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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30 #include <stdlib.h>
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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31
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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32 static
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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33 decode_hex_digit(ch)
d57f68d0568d fc-tch2fr utility written, added under miscutil
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34 {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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35 if (isdigit(ch))
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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36 return(ch - '0');
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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37 else if (isupper(ch))
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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38 return(ch - 'A' + 10);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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39 else
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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40 return(ch - 'a' + 10);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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41 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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42
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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43 main(argc, argv)
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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44 char **argv;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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45 {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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46 FILE *inf, *outf;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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47 char linebuf[128];
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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48 int lineno;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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49 char *cp;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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50 int i, j;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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51 u_char tidsp_bytes[33], libgsm_bytes[33];
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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52
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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53 if (argc != 3) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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54 fprintf(stderr, "usage: %s infile outfile\n", argv[0]);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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55 exit(1);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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56 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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57 inf = fopen(argv[1], "r");
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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58 if (!inf) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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59 perror(argv[1]);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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60 exit(1);
d57f68d0568d fc-tch2fr utility written, added under miscutil
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61 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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62 outf = fopen(argv[2], "w");
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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63 if (!outf) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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64 perror(argv[2]);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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65 exit(1);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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66 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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67 for (lineno = 1; fgets(linebuf, sizeof linebuf, inf); lineno++) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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68 /* skip DSP status words */
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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69 cp = linebuf;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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70 for (i = 0; i < 3; i++) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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71 for (j = 0; j < 4; j++) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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72 if (!isxdigit(*cp++)) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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73 invalid: fprintf(stderr,
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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74 "error: %s is not in the expected format\n",
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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75 argv[1]);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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76 exit(1);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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77 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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78 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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79 if (*cp++ != ' ')
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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80 goto invalid;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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81 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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82 /* read the frame bits */
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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83 for (i = 0; i < 33; i++) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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84 if (!isxdigit(cp[0]) || !isxdigit(cp[1]))
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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85 goto invalid;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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86 tidsp_bytes[i] = (decode_hex_digit(cp[0]) << 4) |
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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87 decode_hex_digit(cp[1]);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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88 cp += 2;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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89 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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90 gsm0610_tidsp_to_libgsm(tidsp_bytes, libgsm_bytes);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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91 fwrite(libgsm_bytes, 1, 33, outf);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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92 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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93 exit(0);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
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94 }