mirror of
https://github.com/ioquake/ioq3.git
synced 2024-11-10 15:21:35 +00:00
357 lines
15 KiB
C
357 lines
15 KiB
C
/***********************************************************************
|
|
Copyright (c) 2006-2011, Skype Limited. All rights reserved.
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions
|
|
are met:
|
|
- Redistributions of source code must retain the above copyright notice,
|
|
this list of conditions and the following disclaimer.
|
|
- Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in the
|
|
documentation and/or other materials provided with the distribution.
|
|
- Neither the name of Internet Society, IETF or IETF Trust, nor the
|
|
names of specific contributors, may be used to endorse or promote
|
|
products derived from this software without specific prior written
|
|
permission.
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
POSSIBILITY OF SUCH DAMAGE.
|
|
***********************************************************************/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "config.h"
|
|
#endif
|
|
|
|
#include "main.h"
|
|
#include "stack_alloc.h"
|
|
|
|
/* Silk VAD noise level estimation */
|
|
static OPUS_INLINE void silk_VAD_GetNoiseLevels(
|
|
const opus_int32 pX[ VAD_N_BANDS ], /* I subband energies */
|
|
silk_VAD_state *psSilk_VAD /* I/O Pointer to Silk VAD state */
|
|
);
|
|
|
|
/**********************************/
|
|
/* Initialization of the Silk VAD */
|
|
/**********************************/
|
|
opus_int silk_VAD_Init( /* O Return value, 0 if success */
|
|
silk_VAD_state *psSilk_VAD /* I/O Pointer to Silk VAD state */
|
|
)
|
|
{
|
|
opus_int b, ret = 0;
|
|
|
|
/* reset state memory */
|
|
silk_memset( psSilk_VAD, 0, sizeof( silk_VAD_state ) );
|
|
|
|
/* init noise levels */
|
|
/* Initialize array with approx pink noise levels (psd proportional to inverse of frequency) */
|
|
for( b = 0; b < VAD_N_BANDS; b++ ) {
|
|
psSilk_VAD->NoiseLevelBias[ b ] = silk_max_32( silk_DIV32_16( VAD_NOISE_LEVELS_BIAS, b + 1 ), 1 );
|
|
}
|
|
|
|
/* Initialize state */
|
|
for( b = 0; b < VAD_N_BANDS; b++ ) {
|
|
psSilk_VAD->NL[ b ] = silk_MUL( 100, psSilk_VAD->NoiseLevelBias[ b ] );
|
|
psSilk_VAD->inv_NL[ b ] = silk_DIV32( silk_int32_MAX, psSilk_VAD->NL[ b ] );
|
|
}
|
|
psSilk_VAD->counter = 15;
|
|
|
|
/* init smoothed energy-to-noise ratio*/
|
|
for( b = 0; b < VAD_N_BANDS; b++ ) {
|
|
psSilk_VAD->NrgRatioSmth_Q8[ b ] = 100 * 256; /* 100 * 256 --> 20 dB SNR */
|
|
}
|
|
|
|
return( ret );
|
|
}
|
|
|
|
/* Weighting factors for tilt measure */
|
|
static const opus_int32 tiltWeights[ VAD_N_BANDS ] = { 30000, 6000, -12000, -12000 };
|
|
|
|
/***************************************/
|
|
/* Get the speech activity level in Q8 */
|
|
/***************************************/
|
|
opus_int silk_VAD_GetSA_Q8( /* O Return value, 0 if success */
|
|
silk_encoder_state *psEncC, /* I/O Encoder state */
|
|
const opus_int16 pIn[] /* I PCM input */
|
|
)
|
|
{
|
|
opus_int SA_Q15, pSNR_dB_Q7, input_tilt;
|
|
opus_int decimated_framelength1, decimated_framelength2;
|
|
opus_int decimated_framelength;
|
|
opus_int dec_subframe_length, dec_subframe_offset, SNR_Q7, i, b, s;
|
|
opus_int32 sumSquared, smooth_coef_Q16;
|
|
opus_int16 HPstateTmp;
|
|
VARDECL( opus_int16, X );
|
|
opus_int32 Xnrg[ VAD_N_BANDS ];
|
|
opus_int32 NrgToNoiseRatio_Q8[ VAD_N_BANDS ];
|
|
opus_int32 speech_nrg, x_tmp;
|
|
opus_int X_offset[ VAD_N_BANDS ];
|
|
opus_int ret = 0;
|
|
silk_VAD_state *psSilk_VAD = &psEncC->sVAD;
|
|
SAVE_STACK;
|
|
|
|
/* Safety checks */
|
|
silk_assert( VAD_N_BANDS == 4 );
|
|
silk_assert( MAX_FRAME_LENGTH >= psEncC->frame_length );
|
|
silk_assert( psEncC->frame_length <= 512 );
|
|
silk_assert( psEncC->frame_length == 8 * silk_RSHIFT( psEncC->frame_length, 3 ) );
|
|
|
|
/***********************/
|
|
/* Filter and Decimate */
|
|
/***********************/
|
|
decimated_framelength1 = silk_RSHIFT( psEncC->frame_length, 1 );
|
|
decimated_framelength2 = silk_RSHIFT( psEncC->frame_length, 2 );
|
|
decimated_framelength = silk_RSHIFT( psEncC->frame_length, 3 );
|
|
/* Decimate into 4 bands:
|
|
0 L 3L L 3L 5L
|
|
- -- - -- --
|
|
8 8 2 4 4
|
|
|
|
[0-1 kHz| temp. |1-2 kHz| 2-4 kHz | 4-8 kHz |
|
|
|
|
They're arranged to allow the minimal ( frame_length / 4 ) extra
|
|
scratch space during the downsampling process */
|
|
X_offset[ 0 ] = 0;
|
|
X_offset[ 1 ] = decimated_framelength + decimated_framelength2;
|
|
X_offset[ 2 ] = X_offset[ 1 ] + decimated_framelength;
|
|
X_offset[ 3 ] = X_offset[ 2 ] + decimated_framelength2;
|
|
ALLOC( X, X_offset[ 3 ] + decimated_framelength1, opus_int16 );
|
|
|
|
/* 0-8 kHz to 0-4 kHz and 4-8 kHz */
|
|
silk_ana_filt_bank_1( pIn, &psSilk_VAD->AnaState[ 0 ],
|
|
X, &X[ X_offset[ 3 ] ], psEncC->frame_length );
|
|
|
|
/* 0-4 kHz to 0-2 kHz and 2-4 kHz */
|
|
silk_ana_filt_bank_1( X, &psSilk_VAD->AnaState1[ 0 ],
|
|
X, &X[ X_offset[ 2 ] ], decimated_framelength1 );
|
|
|
|
/* 0-2 kHz to 0-1 kHz and 1-2 kHz */
|
|
silk_ana_filt_bank_1( X, &psSilk_VAD->AnaState2[ 0 ],
|
|
X, &X[ X_offset[ 1 ] ], decimated_framelength2 );
|
|
|
|
/*********************************************/
|
|
/* HP filter on lowest band (differentiator) */
|
|
/*********************************************/
|
|
X[ decimated_framelength - 1 ] = silk_RSHIFT( X[ decimated_framelength - 1 ], 1 );
|
|
HPstateTmp = X[ decimated_framelength - 1 ];
|
|
for( i = decimated_framelength - 1; i > 0; i-- ) {
|
|
X[ i - 1 ] = silk_RSHIFT( X[ i - 1 ], 1 );
|
|
X[ i ] -= X[ i - 1 ];
|
|
}
|
|
X[ 0 ] -= psSilk_VAD->HPstate;
|
|
psSilk_VAD->HPstate = HPstateTmp;
|
|
|
|
/*************************************/
|
|
/* Calculate the energy in each band */
|
|
/*************************************/
|
|
for( b = 0; b < VAD_N_BANDS; b++ ) {
|
|
/* Find the decimated framelength in the non-uniformly divided bands */
|
|
decimated_framelength = silk_RSHIFT( psEncC->frame_length, silk_min_int( VAD_N_BANDS - b, VAD_N_BANDS - 1 ) );
|
|
|
|
/* Split length into subframe lengths */
|
|
dec_subframe_length = silk_RSHIFT( decimated_framelength, VAD_INTERNAL_SUBFRAMES_LOG2 );
|
|
dec_subframe_offset = 0;
|
|
|
|
/* Compute energy per sub-frame */
|
|
/* initialize with summed energy of last subframe */
|
|
Xnrg[ b ] = psSilk_VAD->XnrgSubfr[ b ];
|
|
for( s = 0; s < VAD_INTERNAL_SUBFRAMES; s++ ) {
|
|
sumSquared = 0;
|
|
for( i = 0; i < dec_subframe_length; i++ ) {
|
|
/* The energy will be less than dec_subframe_length * ( silk_int16_MIN / 8 ) ^ 2. */
|
|
/* Therefore we can accumulate with no risk of overflow (unless dec_subframe_length > 128) */
|
|
x_tmp = silk_RSHIFT(
|
|
X[ X_offset[ b ] + i + dec_subframe_offset ], 3 );
|
|
sumSquared = silk_SMLABB( sumSquared, x_tmp, x_tmp );
|
|
|
|
/* Safety check */
|
|
silk_assert( sumSquared >= 0 );
|
|
}
|
|
|
|
/* Add/saturate summed energy of current subframe */
|
|
if( s < VAD_INTERNAL_SUBFRAMES - 1 ) {
|
|
Xnrg[ b ] = silk_ADD_POS_SAT32( Xnrg[ b ], sumSquared );
|
|
} else {
|
|
/* Look-ahead subframe */
|
|
Xnrg[ b ] = silk_ADD_POS_SAT32( Xnrg[ b ], silk_RSHIFT( sumSquared, 1 ) );
|
|
}
|
|
|
|
dec_subframe_offset += dec_subframe_length;
|
|
}
|
|
psSilk_VAD->XnrgSubfr[ b ] = sumSquared;
|
|
}
|
|
|
|
/********************/
|
|
/* Noise estimation */
|
|
/********************/
|
|
silk_VAD_GetNoiseLevels( &Xnrg[ 0 ], psSilk_VAD );
|
|
|
|
/***********************************************/
|
|
/* Signal-plus-noise to noise ratio estimation */
|
|
/***********************************************/
|
|
sumSquared = 0;
|
|
input_tilt = 0;
|
|
for( b = 0; b < VAD_N_BANDS; b++ ) {
|
|
speech_nrg = Xnrg[ b ] - psSilk_VAD->NL[ b ];
|
|
if( speech_nrg > 0 ) {
|
|
/* Divide, with sufficient resolution */
|
|
if( ( Xnrg[ b ] & 0xFF800000 ) == 0 ) {
|
|
NrgToNoiseRatio_Q8[ b ] = silk_DIV32( silk_LSHIFT( Xnrg[ b ], 8 ), psSilk_VAD->NL[ b ] + 1 );
|
|
} else {
|
|
NrgToNoiseRatio_Q8[ b ] = silk_DIV32( Xnrg[ b ], silk_RSHIFT( psSilk_VAD->NL[ b ], 8 ) + 1 );
|
|
}
|
|
|
|
/* Convert to log domain */
|
|
SNR_Q7 = silk_lin2log( NrgToNoiseRatio_Q8[ b ] ) - 8 * 128;
|
|
|
|
/* Sum-of-squares */
|
|
sumSquared = silk_SMLABB( sumSquared, SNR_Q7, SNR_Q7 ); /* Q14 */
|
|
|
|
/* Tilt measure */
|
|
if( speech_nrg < ( (opus_int32)1 << 20 ) ) {
|
|
/* Scale down SNR value for small subband speech energies */
|
|
SNR_Q7 = silk_SMULWB( silk_LSHIFT( silk_SQRT_APPROX( speech_nrg ), 6 ), SNR_Q7 );
|
|
}
|
|
input_tilt = silk_SMLAWB( input_tilt, tiltWeights[ b ], SNR_Q7 );
|
|
} else {
|
|
NrgToNoiseRatio_Q8[ b ] = 256;
|
|
}
|
|
}
|
|
|
|
/* Mean-of-squares */
|
|
sumSquared = silk_DIV32_16( sumSquared, VAD_N_BANDS ); /* Q14 */
|
|
|
|
/* Root-mean-square approximation, scale to dBs, and write to output pointer */
|
|
pSNR_dB_Q7 = (opus_int16)( 3 * silk_SQRT_APPROX( sumSquared ) ); /* Q7 */
|
|
|
|
/*********************************/
|
|
/* Speech Probability Estimation */
|
|
/*********************************/
|
|
SA_Q15 = silk_sigm_Q15( silk_SMULWB( VAD_SNR_FACTOR_Q16, pSNR_dB_Q7 ) - VAD_NEGATIVE_OFFSET_Q5 );
|
|
|
|
/**************************/
|
|
/* Frequency Tilt Measure */
|
|
/**************************/
|
|
psEncC->input_tilt_Q15 = silk_LSHIFT( silk_sigm_Q15( input_tilt ) - 16384, 1 );
|
|
|
|
/**************************************************/
|
|
/* Scale the sigmoid output based on power levels */
|
|
/**************************************************/
|
|
speech_nrg = 0;
|
|
for( b = 0; b < VAD_N_BANDS; b++ ) {
|
|
/* Accumulate signal-without-noise energies, higher frequency bands have more weight */
|
|
speech_nrg += ( b + 1 ) * silk_RSHIFT( Xnrg[ b ] - psSilk_VAD->NL[ b ], 4 );
|
|
}
|
|
|
|
/* Power scaling */
|
|
if( speech_nrg <= 0 ) {
|
|
SA_Q15 = silk_RSHIFT( SA_Q15, 1 );
|
|
} else if( speech_nrg < 32768 ) {
|
|
if( psEncC->frame_length == 10 * psEncC->fs_kHz ) {
|
|
speech_nrg = silk_LSHIFT_SAT32( speech_nrg, 16 );
|
|
} else {
|
|
speech_nrg = silk_LSHIFT_SAT32( speech_nrg, 15 );
|
|
}
|
|
|
|
/* square-root */
|
|
speech_nrg = silk_SQRT_APPROX( speech_nrg );
|
|
SA_Q15 = silk_SMULWB( 32768 + speech_nrg, SA_Q15 );
|
|
}
|
|
|
|
/* Copy the resulting speech activity in Q8 */
|
|
psEncC->speech_activity_Q8 = silk_min_int( silk_RSHIFT( SA_Q15, 7 ), silk_uint8_MAX );
|
|
|
|
/***********************************/
|
|
/* Energy Level and SNR estimation */
|
|
/***********************************/
|
|
/* Smoothing coefficient */
|
|
smooth_coef_Q16 = silk_SMULWB( VAD_SNR_SMOOTH_COEF_Q18, silk_SMULWB( (opus_int32)SA_Q15, SA_Q15 ) );
|
|
|
|
if( psEncC->frame_length == 10 * psEncC->fs_kHz ) {
|
|
smooth_coef_Q16 >>= 1;
|
|
}
|
|
|
|
for( b = 0; b < VAD_N_BANDS; b++ ) {
|
|
/* compute smoothed energy-to-noise ratio per band */
|
|
psSilk_VAD->NrgRatioSmth_Q8[ b ] = silk_SMLAWB( psSilk_VAD->NrgRatioSmth_Q8[ b ],
|
|
NrgToNoiseRatio_Q8[ b ] - psSilk_VAD->NrgRatioSmth_Q8[ b ], smooth_coef_Q16 );
|
|
|
|
/* signal to noise ratio in dB per band */
|
|
SNR_Q7 = 3 * ( silk_lin2log( psSilk_VAD->NrgRatioSmth_Q8[b] ) - 8 * 128 );
|
|
/* quality = sigmoid( 0.25 * ( SNR_dB - 16 ) ); */
|
|
psEncC->input_quality_bands_Q15[ b ] = silk_sigm_Q15( silk_RSHIFT( SNR_Q7 - 16 * 128, 4 ) );
|
|
}
|
|
|
|
RESTORE_STACK;
|
|
return( ret );
|
|
}
|
|
|
|
/**************************/
|
|
/* Noise level estimation */
|
|
/**************************/
|
|
static OPUS_INLINE void silk_VAD_GetNoiseLevels(
|
|
const opus_int32 pX[ VAD_N_BANDS ], /* I subband energies */
|
|
silk_VAD_state *psSilk_VAD /* I/O Pointer to Silk VAD state */
|
|
)
|
|
{
|
|
opus_int k;
|
|
opus_int32 nl, nrg, inv_nrg;
|
|
opus_int coef, min_coef;
|
|
|
|
/* Initially faster smoothing */
|
|
if( psSilk_VAD->counter < 1000 ) { /* 1000 = 20 sec */
|
|
min_coef = silk_DIV32_16( silk_int16_MAX, silk_RSHIFT( psSilk_VAD->counter, 4 ) + 1 );
|
|
} else {
|
|
min_coef = 0;
|
|
}
|
|
|
|
for( k = 0; k < VAD_N_BANDS; k++ ) {
|
|
/* Get old noise level estimate for current band */
|
|
nl = psSilk_VAD->NL[ k ];
|
|
silk_assert( nl >= 0 );
|
|
|
|
/* Add bias */
|
|
nrg = silk_ADD_POS_SAT32( pX[ k ], psSilk_VAD->NoiseLevelBias[ k ] );
|
|
silk_assert( nrg > 0 );
|
|
|
|
/* Invert energies */
|
|
inv_nrg = silk_DIV32( silk_int32_MAX, nrg );
|
|
silk_assert( inv_nrg >= 0 );
|
|
|
|
/* Less update when subband energy is high */
|
|
if( nrg > silk_LSHIFT( nl, 3 ) ) {
|
|
coef = VAD_NOISE_LEVEL_SMOOTH_COEF_Q16 >> 3;
|
|
} else if( nrg < nl ) {
|
|
coef = VAD_NOISE_LEVEL_SMOOTH_COEF_Q16;
|
|
} else {
|
|
coef = silk_SMULWB( silk_SMULWW( inv_nrg, nl ), VAD_NOISE_LEVEL_SMOOTH_COEF_Q16 << 1 );
|
|
}
|
|
|
|
/* Initially faster smoothing */
|
|
coef = silk_max_int( coef, min_coef );
|
|
|
|
/* Smooth inverse energies */
|
|
psSilk_VAD->inv_NL[ k ] = silk_SMLAWB( psSilk_VAD->inv_NL[ k ], inv_nrg - psSilk_VAD->inv_NL[ k ], coef );
|
|
silk_assert( psSilk_VAD->inv_NL[ k ] >= 0 );
|
|
|
|
/* Compute noise level by inverting again */
|
|
nl = silk_DIV32( silk_int32_MAX, psSilk_VAD->inv_NL[ k ] );
|
|
silk_assert( nl >= 0 );
|
|
|
|
/* Limit noise levels (guarantee 7 bits of head room) */
|
|
nl = silk_min( nl, 0x00FFFFFF );
|
|
|
|
/* Store as part of state */
|
|
psSilk_VAD->NL[ k ] = nl;
|
|
}
|
|
|
|
/* Increment frame counter */
|
|
psSilk_VAD->counter++;
|
|
}
|