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Diffstat (limited to 'media/libstagefright/codecs/amrnb/common/include/cnst_vad.h')
| -rw-r--r-- | media/libstagefright/codecs/amrnb/common/include/cnst_vad.h | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/media/libstagefright/codecs/amrnb/common/include/cnst_vad.h b/media/libstagefright/codecs/amrnb/common/include/cnst_vad.h new file mode 100644 index 0000000..6877a1b --- /dev/null +++ b/media/libstagefright/codecs/amrnb/common/include/cnst_vad.h @@ -0,0 +1,133 @@ +/* ------------------------------------------------------------------ + * Copyright (C) 1998-2009 PacketVideo + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either + * express or implied. + * See the License for the specific language governing permissions + * and limitations under the License. + * ------------------------------------------------------------------- + */ +/**************************************************************************************** +Portions of this file are derived from the following 3GPP standard: + + 3GPP TS 26.073 + ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec + Available from http://www.3gpp.org + +(C) 2004, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC) +Permission to distribute, modify and use this file under the standard license +terms listed above has been obtained from the copyright holder. +****************************************************************************************/ +/* +******************************************************************************** +**-------------------------------------------------------------------------** +** ** +** GSM AMR-NB speech codec R98 Version 7.5.0 March 2, 2001 ** +** R99 Version 3.2.0 ** +** REL-4 Version 4.0.0 ** +** ** +**-------------------------------------------------------------------------** +******************************************************************************** +* +* 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 |