FreeCalypso > hg > gsm-codec-lib
view hrutil/tw5b-out-cod.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 | 129c895a0564 |
| children |
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/* * The helper function implemented in this module emits TW-TS-005 Annex B * hex output based on an encoder output array, i.e., a cod-style frame. * This helper function will be used for gsmhr-cod2hex, gsmhr-encode[-r] * and gsmhr-tfo-xfrm utilities. */ #include <stdint.h> #include <stdio.h> #include "../libgsmhr1/tw_gsmhr.h" #include "../libtest/tw5writer.h" void emit_cod_to_tw5b(outf, params, emit_5993) FILE *outf; int16_t *params; { uint8_t frame[GSMHR_FRAME_LEN_5993]; gsmhr_encoder_twts002_out(params, frame); if (emit_5993) emit_hex_frame(outf, frame, GSMHR_FRAME_LEN_5993); else emit_hex_frame(outf, frame + 1, GSMHR_FRAME_LEN_RPF); }
