FreeCalypso > hg > gsm-codec-lib
view miscutil/raw2wav.c @ 605:63f774192906
gsmhr_decoder_twts002_in(): set BFI=1 SID=1 for invalid SID
When a received TW-TS-002 RTP payload indicates invalid SID,
which of the 3 possible BFI/SID combinations should we pass to
our internal ETSI-based speech decoder or TFO engine?
Our original code passed BFI=0 SID=1, but upon further reflection,
BFI=1 SID=1 is a better choice. In the corner case where received
invalid SID is fed to a full decoder in homed state, setting BFI=1
allows that decoder to emit zeros on PCM and stay homed, instead of
launching into full decoding.
| author | Mychaela Falconia <falcon@freecalypso.org> |
|---|---|
| date | Thu, 04 Dec 2025 21:01:46 +0000 |
| parents | c1dc094f0821 |
| children |
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/* * This program reads a 16-bit linear PCM speech recording in raw format * (either BE or LE) and converts it into WAV container format. */ #include <stdio.h> #include <stdint.h> #include <stdlib.h> #include <string.h> #include <strings.h> #include "../libtest/wavwriter.h" static void swap_bytes(bytes, cc) uint8_t *bytes; unsigned cc; { uint8_t *dp, *endp; int t; dp = bytes; endp = bytes + cc; while (dp < endp) { t = dp[0]; dp[0] = dp[1]; dp[1] = t; dp += 2; } } main(argc, argv) char **argv; { int big_endian; FILE *binf; void *wav; uint8_t bytes[320]; int cc; if (argc != 4) { usage: fprintf(stderr, "usage: %s be|le input.raw output.wav\n", argv[0]); exit(1); } if (!strcmp(argv[1], "be")) big_endian = 1; else if (!strcmp(argv[1], "le")) big_endian = 0; else goto usage; binf = fopen(argv[2], "r"); if (!binf) { perror(argv[2]); exit(1); } wav = wav_write_open(argv[3], 8000, 16, 1); if (!wav) { perror(argv[3]); exit(1); } for (;;) { cc = fread(bytes, 1, sizeof bytes, binf); if (cc <= 0) break; if (cc & 1) { fprintf(stderr, "error: %s has odd number of bytes\n", argv[2]); exit(1); } if (big_endian) swap_bytes(bytes, cc); wav_write_data(wav, bytes, cc); } wav_write_close(wav); exit(0); }
