FreeCalypso > hg > gsm-codec-lib
view libtwamr/tls_flags.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 | dfb1f86541b2 |
| children |
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/* * Unfortunately the code we got from ETSI makes heavy use of two global * Boolean flags named Carry and Overflow that function like equally named * processor state flags on many CPU architectures. They are not part * of persistent codec session state for either the encoder or the decoder, * instead they are "short-term" globals much like UNIX errno. * * Given this unfortunate reality plus the natural desire to make our * AMR library thread-safe (a transcoding MGW handling a large volume of * simultaneous calls is exactly the kind of application that would benefit * from utilitizing all CPU cores), our current workaround is to use * thread-local storage. */ #include "typedef.h" #include "namespace.h" __thread Flag Carry, Overflow;
