FreeCalypso > hg > gsm-codec-lib
view libtest/robewrite.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 | 14b627682458 |
| children |
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/* * Here we implement our PCM write helper function for "robe" format. */ #include <stdio.h> #include <stdint.h> #include "robewrite.h" void write_pcm_to_robe(FILE *outf, const int16_t *pcm) { uint8_t bytes[320], *dp; int16_t samp; unsigned n; dp = bytes; for (n = 0; n < 160; n++) { samp = pcm[n]; *dp++ = (samp >> 8) & 0xFF; *dp++ = samp & 0xFF; } fwrite(bytes, 2, 160, outf); }
