FreeCalypso > hg > gsm-codec-lib
view libtwamr/bgnscd.h @ 422:1ceda5586d01
implement twamr-tseq-enc test program
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Tue, 07 May 2024 06:27:20 +0000 |
parents | 8dfb7cbe6b59 |
children |
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/* ******************************************************************************** * * 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 : bgnscd.h * Purpose : Background noise source charateristic detector (SCD) * ******************************************************************************** */ #ifndef bgnscd_h #define bgnscd_h "$Id $" /* ******************************************************************************** * INCLUDE FILES ******************************************************************************** */ #include "typedef.h" #include "cnst.h" /* ******************************************************************************** * LOCAL VARIABLES AND TABLES ******************************************************************************** */ #define L_ENERGYHIST 60 #define INV_L_FRAME 102 /* 2*(160*x)^2 / 65536 where x is FLP values 150,5 and 50 */ #define FRAMEENERGYLIMIT 17578 /* 150 */ #define LOWERNOISELIMIT 20 /* 5 */ #define UPPERNOISELIMIT 1953 /* 50 */ /* ******************************************************************************** * DEFINITION OF DATA TYPES ******************************************************************************** */ typedef struct{ /* history vector of past synthesis speech energy */ Word16 frameEnergyHist[L_ENERGYHIST]; /* state flags */ Word16 bgHangover; /* counter; number of frames after last speech frame */ } Bgn_scdState; /* ******************************************************************************** * DECLARATION OF PROTOTYPES ******************************************************************************** */ /* ************************************************************************** * * Function : Bgn_scd_reset * Purpose : Resets state memory * Returns : 0 on success * ************************************************************************** */ void Bgn_scd_reset (Bgn_scdState *st); /* ************************************************************************** * * Function : Bgn_scd * Purpose : Charaterice synthesis speech and detect background noise * Returns : background noise decision; 0 = bgn, 1 = no bgn * ************************************************************************** */ Word16 Bgn_scd (Bgn_scdState *st, /* i : State variables for bgn SCD */ Word16 ltpGainHist[], /* i : LTP gain history */ Word16 speech[], /* o : synthesis speech frame */ Word16 *voicedHangover /* o : # of frames after last voiced frame */ ); #endif