FreeCalypso > hg > gsm-codec-lib
view frtest/encode.c @ 604:54f0f1b74c25
libgsmhr1 TFO: require BFI=0 and SID=0 for homing
In order for a received frame to be recognized as DHF, we need
not only the correct bit pattern, but also BFI=0 and SID=0.
The BFI=0 requirement should be obvious, while the SID=0 requirement
is needed only for HR codec. With FR and EFR, SID classification
comes from the payload bits and no separate check is needed -
but in HR we get an out-of-band SID ternary flag. When SID=1,
no payload bits are used at all; when SID=2, we use only the first
33 bits of the payload. Therefore, it is proper to conditionalize
DHF acceptance on SID=0.
We already implemented this logic in the just finished full decoder;
now bring TFO code into agreement.
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Thu, 04 Dec 2025 19:40:35 +0000 |
| parents | f00925b533b7 |
| children |
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/* * This file is the main module for gsmfr-encode utility. */ #include <stdio.h> #include <stdint.h> #include <stdlib.h> #include "../libgsmfr2/tw_gsmfr.h" #include "../libtest/wavreader.h" #include "../libtest/wavrdhelp.h" main(argc, argv) char **argv; { void *wav; FILE *binf; struct gsmfr_0610_state *enc_state; int16_t pcm[160]; uint8_t frame[33]; int rc; if (argc != 3) { fprintf(stderr, "usage: %s input.wav output.gsm\n", argv[0]); exit(1); } wav = wav_read_open(argv[1]); if (!wav) { perror(argv[1]); exit(1); } rc = wavrd_check_header(wav, argv[1]); if (rc < 0) exit(1); /* error msg already printed */ binf = fopen(argv[2], "w"); if (!binf) { perror(argv[2]); exit(1); } enc_state = gsmfr_0610_create(); if (!enc_state) { fprintf(stderr, "gsmfr_0610_create() failed!\n"); exit(1); } for (;;) { rc = wavrd_get_pcm_block(wav, pcm); if (!rc) break; gsmfr_0610_encode_frame(enc_state, pcm, frame); fwrite(frame, 1, sizeof frame, binf); } fclose(binf); exit(0); }
