FreeCalypso > hg > freecalypso-tools

annotate miscutil/fc-tch2fr.c @ 207:d1eb8518f23d

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
rfcal/Makefile: tsid-test added to SUBDIR
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 14 May 2017 23:09:27 +0000
parents d57f68d0568d
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
6
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 /*
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
8 * whether the decoded speech frame is good or bad.
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9 *
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
18 * decoder.
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19 *
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20 * The present utility reproduces the naive behaviour of my previous
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
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>
parents:
diff changeset
24 * into libgsm format.
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
25 */
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
26
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
27 #include <sys/types.h>
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
28 #include <ctype.h>
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
29 #include <stdio.h>
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
30 #include <stdlib.h>
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
31
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
32 static
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
33 decode_hex_digit(ch)
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
34 {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
35 if (isdigit(ch))
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
36 return(ch - '0');
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
37 else if (isupper(ch))
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
38 return(ch - 'A' + 10);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
39 else
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
40 return(ch - 'a' + 10);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
41 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
42
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
43 main(argc, argv)
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
44 char **argv;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
45 {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
46 FILE *inf, *outf;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
47 char linebuf[128];
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
48 int lineno;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
49 char *cp;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
50 int i, j;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
51 u_char tidsp_bytes[33], libgsm_bytes[33];
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
52
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
53 if (argc != 3) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
54 fprintf(stderr, "usage: %s infile outfile\n", argv[0]);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
55 exit(1);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
56 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
57 inf = fopen(argv[1], "r");
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
58 if (!inf) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
59 perror(argv[1]);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
60 exit(1);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
61 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
62 outf = fopen(argv[2], "w");
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
63 if (!outf) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
64 perror(argv[2]);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
65 exit(1);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
66 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
67 for (lineno = 1; fgets(linebuf, sizeof linebuf, inf); lineno++) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
68 /* skip DSP status words */
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
69 cp = linebuf;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
70 for (i = 0; i < 3; i++) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
71 for (j = 0; j < 4; j++) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
72 if (!isxdigit(*cp++)) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
73 invalid: fprintf(stderr,
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
74 "error: %s is not in the expected format\n",
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
75 argv[1]);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
76 exit(1);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
77 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
78 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
79 if (*cp++ != ' ')
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
80 goto invalid;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
81 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
82 /* read the frame bits */
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
83 for (i = 0; i < 33; i++) {
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
84 if (!isxdigit(cp[0]) || !isxdigit(cp[1]))
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
85 goto invalid;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
86 tidsp_bytes[i] = (decode_hex_digit(cp[0]) << 4) |
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
87 decode_hex_digit(cp[1]);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
88 cp += 2;
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
89 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
90 gsm0610_tidsp_to_libgsm(tidsp_bytes, libgsm_bytes);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
91 fwrite(libgsm_bytes, 1, 33, outf);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
92 }
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
93 exit(0);
d57f68d0568d fc-tch2fr utility written, added under miscutil
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
94 }