FreeCalypso > hg > gsm-codec-lib
view libtwamr/c_g_aver.h @ 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 | dc3b7caa59c4 |
| children |
line wrap: on
line source
/* ******************************************************************************** * * GSM AMR-NB speech codec R98 Version 7.6.0 December 12, 2001 * R99 Version 3.3.0 * REL-4 Version 4.1.0 * ******************************************************************************** * * File : c_g_aver.h * Purpose : Background noise source charateristic detector (SCD) * ******************************************************************************** */ #ifndef c_g_aver_h #define c_g_aver_h "$Id $" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "tw_amr.h" #include "typedef.h" #include "cnst.h" /* ******************************************************************************** * LOCAL VARIABLES AND TABLES ******************************************************************************** */ #define L_CBGAINHIST 7 /* ******************************************************************************** * DEFINITION OF DATA TYPES ******************************************************************************** */ typedef struct{ /* history vector of past synthesis speech energy */ Word16 cbGainHistory[L_CBGAINHIST]; /* state flags */ Word16 hangVar; /* counter; */ Word16 hangCount; /* counter; */ } Cb_gain_averageState; /* ******************************************************************************** * DECLARATION OF PROTOTYPES ******************************************************************************** */ /* ************************************************************************** * * Function : Cb_gain_average_reset * Purpose : Resets state memory * Returns : 0 on success * ************************************************************************** */ void Cb_gain_average_reset (Cb_gain_averageState *st); /* ************************************************************************** * * Function : Cb_gain_average * Purpose : Charaterice synthesis speech and detect background noise * Returns : background noise decision; 0 = bgn, 1 = no bgn * ************************************************************************** */ Word16 Cb_gain_average ( Cb_gain_averageState *st, /* i/o : State variables for CB gain avergeing */ enum Mode mode, /* i : AMR mode */ Word16 gain_code, /* i : CB gain Q1 */ Word16 lsp[], /* i : The LSP for the current frame Q15 */ Word16 lspAver[], /* i : The average of LSP for 8 frames Q15 */ Word16 bfi, /* i : bad frame indication flag */ Word16 prev_bf, /* i : previous bad frame indication flag */ Word16 pdfi, /* i : potential degraded bad frame ind flag */ Word16 prev_pdf, /* i : prev pot. degraded bad frame ind flag */ Word16 inBackgroundNoise, /* i : background noise decision */ Word16 voicedHangover /* i : # of frames after last voiced frame */ ); #endif