FreeCalypso > hg > gsm-codec-lib
view libtwamr/cnst_vad.h @ 482:5e2d849a4fbc
doc/Calypso-TCH-downlink: grammar fix
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Mon, 20 May 2024 01:24:22 +0000 |
parents | 8847c1740e78 |
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 : cnst_vad.h * Purpose : Constants and definitions for VAD * ******************************************************************************** */ #ifndef cnst_vad_h #define cnst_vad_h "$Id $" #define FRAME_LEN 160 /* Length (samples) of the input frame */ #define COMPLEN 9 /* Number of sub-bands used by VAD */ #define INV_COMPLEN 3641 /* 1.0/COMPLEN*2^15 */ #define LOOKAHEAD 40 /* length of the lookahead used by speech coder */ #define UNITY 512 /* Scaling used with SNR calculation */ #define UNIRSHFT 6 /* = log2(MAX_16/UNITY) */ #define TONE_THR (Word16)(0.65*MAX_16) /* Threshold for tone detection */ /* Constants for background spectrum update */ #define ALPHA_UP1 (Word16)((1.0 - 0.95)*MAX_16) /* Normal update, upwards: */ #define ALPHA_DOWN1 (Word16)((1.0 - 0.936)*MAX_16) /* Normal update, downwards */ #define ALPHA_UP2 (Word16)((1.0 - 0.985)*MAX_16) /* Forced update, upwards */ #define ALPHA_DOWN2 (Word16)((1.0 - 0.943)*MAX_16) /* Forced update, downwards */ #define ALPHA3 (Word16)((1.0 - 0.95)*MAX_16) /* Update downwards */ #define ALPHA4 (Word16)((1.0 - 0.9)*MAX_16) /* For stationary estimation */ #define ALPHA5 (Word16)((1.0 - 0.5)*MAX_16) /* For stationary estimation */ /* Constants for VAD threshold */ #define VAD_THR_HIGH 1260 /* Highest threshold */ #define VAD_THR_LOW 720 /* Lowest threshold */ #define VAD_P1 0 /* Noise level for highest threshold */ #define VAD_P2 6300 /* Noise level for lowest threshold */ #define VAD_SLOPE (Word16)(MAX_16*(float)(VAD_THR_LOW-VAD_THR_HIGH)/(float)(VAD_P2-VAD_P1)) /* Parameters for background spectrum recovery function */ #define STAT_COUNT 20 /* threshold of stationary detection counter */ #define STAT_COUNT_BY_2 10 /* threshold of stationary detection counter */ #define CAD_MIN_STAT_COUNT 5 /* threshold of stationary detection counter */ #define STAT_THR_LEVEL 184 /* Threshold level for stationarity detection */ #define STAT_THR 1000 /* Threshold for stationarity detection */ /* Limits for background noise estimate */ #define NOISE_MIN 40 /* minimum */ #define NOISE_MAX 16000 /* maximum */ #define NOISE_INIT 150 /* initial */ /* Constants for VAD hangover addition */ #define HANG_NOISE_THR 100 #define BURST_LEN_HIGH_NOISE 4 #define HANG_LEN_HIGH_NOISE 7 #define BURST_LEN_LOW_NOISE 5 #define HANG_LEN_LOW_NOISE 4 /* Thresholds for signal power */ #define VAD_POW_LOW (Word32)15000 /* If input power is lower, */ /* VAD is set to 0 */ #define POW_PITCH_THR (Word32)343040 /* If input power is lower, pitch */ /* detection is ignored */ #define POW_COMPLEX_THR (Word32)15000 /* If input power is lower, complex */ /* flags value for previous frame is un-set */ /* Constants for the filter bank */ #define LEVEL_SHIFT 0 /* scaling */ #define COEFF3 13363 /* coefficient for the 3rd order filter */ #define COEFF5_1 21955 /* 1st coefficient the for 5th order filter */ #define COEFF5_2 6390 /* 2nd coefficient the for 5th order filter */ /* Constants for pitch detection */ #define LTHRESH 4 #define NTHRESH 4 /* Constants for complex signal VAD */ #define CVAD_THRESH_ADAPT_HIGH (Word16)(0.6 * MAX_16) /* threshold for adapt stopping high */ #define CVAD_THRESH_ADAPT_LOW (Word16)(0.5 * MAX_16) /* threshold for adapt stopping low */ #define CVAD_THRESH_IN_NOISE (Word16)(0.65 * MAX_16) /* threshold going into speech on a short term basis */ #define CVAD_THRESH_HANG (Word16)(0.70 * MAX_16) /* threshold */ #define CVAD_HANG_LIMIT (Word16)(100) /* 2 second estimation time */ #define CVAD_HANG_LENGTH (Word16)(250) /* 5 second hangover */ #define CVAD_LOWPOW_RESET (Word16) (0.40 * MAX_16) /* init in low power segment */ #define CVAD_MIN_CORR (Word16) (0.40 * MAX_16) /* lowest adaptation value */ #define CVAD_BURST 20 /* speech burst length for speech reset */ #define CVAD_ADAPT_SLOW (Word16)(( 1.0 - 0.98) * MAX_16) /* threshold for slow adaption */ #define CVAD_ADAPT_FAST (Word16)((1.0 - 0.92) * MAX_16) /* threshold for fast adaption */ #define CVAD_ADAPT_REALLY_FAST (Word16)((1.0 - 0.80) * MAX_16) /* threshold for really fast adaption */ #endif