ref: 221486c5526d96794e5257e55b2b07459861225f
dir: /amr-wb/wb_vad_c.h/
/*-------------------------------------------------------------------* * WB_VAD_C.H * *-------------------------------------------------------------------* * Constants for Voice Activity Detection. * *-------------------------------------------------------------------*/ #ifndef wb_vad_c_h #define wb_vad_c_h #define FRAME_LEN 256 /* Length (samples) of the input frame */ #define COMPLEN 12 /* Number of sub-bands used by VAD */ #define UNIRSHFT 7 /* = log2(MAX_16/UNITY), UNITY = 256 */ #define SCALE 128 /* (UNITY*UNITY)/512 */ #define TONE_THR (Word16)(0.65*MAX_16) /* Threshold for tone detection */ /* constants for speech level estimation */ #define SP_EST_COUNT 80 #define SP_ACTIVITY_COUNT 25 #define ALPHA_SP_UP (Word16)((1.0 - 0.85)*MAX_16) #define ALPHA_SP_DOWN (Word16)((1.0 - 0.85)*MAX_16) #define NOM_LEVEL 2050 /* about -26 dBov Q15 */ #define SPEECH_LEVEL_INIT NOM_LEVEL /* initial speech level */ #define MIN_SPEECH_LEVEL1 (Word16)(NOM_LEVEL * 0.063) /* NOM_LEVEL -24 dB */ #define MIN_SPEECH_LEVEL2 (Word16)(NOM_LEVEL * 0.2) /* NOM_LEVEL -14 dB */ #define MIN_SPEECH_SNR 4096 /* 0 dB, lowest SNR estimation, Q12 */ /* Time 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 THR_MIN (Word16)(1.6*SCALE) /* Minimum threshold */ #define THR_HIGH (Word16)(6*SCALE) /* Highest threshold */ #define THR_LOW (Word16)(1.7*SCALE) /* Lowest threshold */ #define NO_P1 31744 /* ilog2(1), Noise level for highest threshold */ #define NO_P2 19786 /* ilog2(0.1*MAX_16), Noise level for lowest threshold */ #define NO_SLOPE (Word16)(MAX_16*(float)(THR_LOW-THR_HIGH)/(float)(NO_P2-NO_P1)) #define SP_CH_MIN (Word16)(-0.75*SCALE) #define SP_CH_MAX (Word16)(0.75*SCALE) #define SP_P1 22527 /* ilog2(NOM_LEVEL/4) */ #define SP_P2 17832 /* ilog2(NOM_LEVEL*4) */ #define SP_SLOPE (Word16)(MAX_16*(float)(SP_CH_MAX-SP_CH_MIN)/(float)(SP_P2-SP_P1)) /* Constants for hangover length */ #define HANG_HIGH 12 /* longest hangover */ #define HANG_LOW 2 /* shortest hangover */ #define HANG_P1 THR_LOW /* threshold for longest hangover */ #define HANG_P2 (Word16)(4*SCALE) /* threshold for shortest hangover */ #define HANG_SLOPE (Word16)(MAX_16*(float)(HANG_LOW-HANG_HIGH)/(float)(HANG_P2-HANG_P1)) /* Constants for burst length */ #define BURST_HIGH 8 /* longest burst length */ #define BURST_LOW 3 /* shortest burst length */ #define BURST_P1 THR_HIGH /* threshold for longest burst */ #define BURST_P2 THR_LOW /* threshold for shortest burst */ #define BURST_SLOPE (Word16)(MAX_16*(float)(BURST_LOW-BURST_HIGH)/(float)(BURST_P2-BURST_P1)) /* Parameters for background spectrum recovery function */ #define STAT_COUNT 20 /* 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 20000 /* maximum */ #define NOISE_INIT 150 /* initial */ /* Thresholds for signal power (now calculated on 2 frames) */ #define VAD_POW_LOW (Word32)30000L /* If input power is lower than this, VAD is set to 0 */ #define POW_TONE_THR (Word32)686080L /* If input power is lower,tone detection flag is ignored */ /* Constants for the filter bank */ #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 */ #define F_5TH_CNT 5 /* number of 5th order filters */ #define F_3TH_CNT 6 /* number of 3th order filters */ #endif