1 /* 2 ** Copyright 2003-2010, VisualOn, Inc. 3 ** 4 ** Licensed under the Apache License, Version 2.0 (the "License"); 5 ** you may not use this file except in compliance with the License. 6 ** You may obtain a copy of the License at 7 ** 8 ** http://www.apache.org/licenses/LICENSE-2.0 9 ** 10 ** Unless required by applicable law or agreed to in writing, software 11 ** distributed under the License is distributed on an "AS IS" BASIS, 12 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 ** See the License for the specific language governing permissions and 14 ** limitations under the License. 15 */ 16 17 18 /*-------------------------------------------------------------------* 19 * WB_VAD_C.H * 20 *-------------------------------------------------------------------* 21 * Constants for Voice Activity Detection. * 22 *-------------------------------------------------------------------*/ 23 24 #ifndef __WB_VAD_C_H__ 25 #define __WB_VAD_C_H__ 26 27 #define FRAME_LEN 256 /* Length (samples) of the input frame */ 28 #define COMPLEN 12 /* Number of sub-bands used by VAD */ 29 30 #define UNIRSHFT 7 /* = log2(MAX_16/UNITY), UNITY = 256 */ 31 #define SCALE 128 /* (UNITY*UNITY)/512 */ 32 33 #define TONE_THR (Word16)(0.65*MAX_16) /* Threshold for tone detection */ 34 35 /* constants for speech level estimation */ 36 #define SP_EST_COUNT 80 37 #define SP_ACTIVITY_COUNT 25 38 #define ALPHA_SP_UP (Word16)((1.0 - 0.85)*MAX_16) 39 #define ALPHA_SP_DOWN (Word16)((1.0 - 0.85)*MAX_16) 40 41 #define NOM_LEVEL 2050 /* about -26 dBov Q15 */ 42 #define SPEECH_LEVEL_INIT NOM_LEVEL /* initial speech level */ 43 #define MIN_SPEECH_LEVEL1 (Word16)(NOM_LEVEL * 0.063) /* NOM_LEVEL -24 dB */ 44 #define MIN_SPEECH_LEVEL2 (Word16)(NOM_LEVEL * 0.2) /* NOM_LEVEL -14 dB */ 45 #define MIN_SPEECH_SNR 4096 /* 0 dB, lowest SNR estimation, Q12 */ 46 47 /* Time constants for background spectrum update */ 48 #define ALPHA_UP1 (Word16)((1.0 - 0.95)*MAX_16) /* Normal update, upwards: */ 49 #define ALPHA_DOWN1 (Word16)((1.0 - 0.936)*MAX_16) /* Normal update, downwards */ 50 #define ALPHA_UP2 (Word16)((1.0 - 0.985)*MAX_16) /* Forced update, upwards */ 51 #define ALPHA_DOWN2 (Word16)((1.0 - 0.943)*MAX_16) /* Forced update, downwards */ 52 #define ALPHA3 (Word16)((1.0 - 0.95)*MAX_16) /* Update downwards */ 53 #define ALPHA4 (Word16)((1.0 - 0.9)*MAX_16) /* For stationary estimation */ 54 #define ALPHA5 (Word16)((1.0 - 0.5)*MAX_16) /* For stationary estimation */ 55 56 /* Constants for VAD threshold */ 57 #define THR_MIN (Word16)(1.6*SCALE) /* Minimum threshold */ 58 #define THR_HIGH (Word16)(6*SCALE) /* Highest threshold */ 59 #define THR_LOW (Word16)(1.7*SCALE) /* Lowest threshold */ 60 #define NO_P1 31744 /* ilog2(1), Noise level for highest threshold */ 61 #define NO_P2 19786 /* ilog2(0.1*MAX_16), Noise level for lowest threshold */ 62 #define NO_SLOPE (Word16)(MAX_16*(float)(THR_LOW-THR_HIGH)/(float)(NO_P2-NO_P1)) 63 64 #define SP_CH_MIN (Word16)(-0.75*SCALE) 65 #define SP_CH_MAX (Word16)(0.75*SCALE) 66 #define SP_P1 22527 /* ilog2(NOM_LEVEL/4) */ 67 #define SP_P2 17832 /* ilog2(NOM_LEVEL*4) */ 68 #define SP_SLOPE (Word16)(MAX_16*(float)(SP_CH_MAX-SP_CH_MIN)/(float)(SP_P2-SP_P1)) 69 70 /* Constants for hangover length */ 71 #define HANG_HIGH 12 /* longest hangover */ 72 #define HANG_LOW 2 /* shortest hangover */ 73 #define HANG_P1 THR_LOW /* threshold for longest hangover */ 74 #define HANG_P2 (Word16)(4*SCALE) /* threshold for shortest hangover */ 75 #define HANG_SLOPE (Word16)(MAX_16*(float)(HANG_LOW-HANG_HIGH)/(float)(HANG_P2-HANG_P1)) 76 77 /* Constants for burst length */ 78 #define BURST_HIGH 8 /* longest burst length */ 79 #define BURST_LOW 3 /* shortest burst length */ 80 #define BURST_P1 THR_HIGH /* threshold for longest burst */ 81 #define BURST_P2 THR_LOW /* threshold for shortest burst */ 82 #define BURST_SLOPE (Word16)(MAX_16*(float)(BURST_LOW-BURST_HIGH)/(float)(BURST_P2-BURST_P1)) 83 84 /* Parameters for background spectrum recovery function */ 85 #define STAT_COUNT 20 /* threshold of stationary detection counter */ 86 87 #define STAT_THR_LEVEL 184 /* Threshold level for stationarity detection */ 88 #define STAT_THR 1000 /* Threshold for stationarity detection */ 89 90 /* Limits for background noise estimate */ 91 #define NOISE_MIN 40 /* minimum */ 92 #define NOISE_MAX 20000 /* maximum */ 93 #define NOISE_INIT 150 /* initial */ 94 95 /* Thresholds for signal power (now calculated on 2 frames) */ 96 #define VAD_POW_LOW (Word32)30000L /* If input power is lower than this, VAD is set to 0 */ 97 #define POW_TONE_THR (Word32)686080L /* If input power is lower,tone detection flag is ignored */ 98 99 /* Constants for the filter bank */ 100 #define COEFF3 13363 /* coefficient for the 3rd order filter */ 101 #define COEFF5_1 21955 /* 1st coefficient the for 5th order filter */ 102 #define COEFF5_2 6390 /* 2nd coefficient the for 5th order filter */ 103 #define F_5TH_CNT 5 /* number of 5th order filters */ 104 #define F_3TH_CNT 6 /* number of 3th order filters */ 105 106 #endif //__WB_VAD_C_H__ 107 108 109 110