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;