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Diffstat (limited to 'src/opus-1.0.2/silk/VAD.c')
| -rw-r--r-- | src/opus-1.0.2/silk/VAD.c | 330 |
1 files changed, 0 insertions, 330 deletions
diff --git a/src/opus-1.0.2/silk/VAD.c b/src/opus-1.0.2/silk/VAD.c deleted file mode 100644 index bac89b44..00000000 --- a/src/opus-1.0.2/silk/VAD.c +++ /dev/null @@ -1,330 +0,0 @@ -/*********************************************************************** -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" - -/* Silk VAD noise level estimation */ -static 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_framelength, dec_subframe_length, dec_subframe_offset, SNR_Q7, i, b, s; - opus_int32 sumSquared, smooth_coef_Q16; - opus_int16 HPstateTmp; - opus_int16 X[ VAD_N_BANDS ][ MAX_FRAME_LENGTH / 2 ]; - opus_int32 Xnrg[ VAD_N_BANDS ]; - opus_int32 NrgToNoiseRatio_Q8[ VAD_N_BANDS ]; - opus_int32 speech_nrg, x_tmp; - opus_int ret = 0; - silk_VAD_state *psSilk_VAD = &psEncC->sVAD; - - /* 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 */ - /***********************/ - /* 0-8 kHz to 0-4 kHz and 4-8 kHz */ - silk_ana_filt_bank_1( pIn, &psSilk_VAD->AnaState[ 0 ], &X[ 0 ][ 0 ], &X[ 3 ][ 0 ], psEncC->frame_length ); - - /* 0-4 kHz to 0-2 kHz and 2-4 kHz */ - silk_ana_filt_bank_1( &X[ 0 ][ 0 ], &psSilk_VAD->AnaState1[ 0 ], &X[ 0 ][ 0 ], &X[ 2 ][ 0 ], silk_RSHIFT( psEncC->frame_length, 1 ) ); - - /* 0-2 kHz to 0-1 kHz and 1-2 kHz */ - silk_ana_filt_bank_1( &X[ 0 ][ 0 ], &psSilk_VAD->AnaState2[ 0 ], &X[ 0 ][ 0 ], &X[ 1 ][ 0 ], silk_RSHIFT( psEncC->frame_length, 2 ) ); - - /*********************************************/ - /* HP filter on lowest band (differentiator) */ - /*********************************************/ - decimated_framelength = silk_RSHIFT( psEncC->frame_length, 3 ); - X[ 0 ][ decimated_framelength - 1 ] = silk_RSHIFT( X[ 0 ][ decimated_framelength - 1 ], 1 ); - HPstateTmp = X[ 0 ][ decimated_framelength - 1 ]; - for( i = decimated_framelength - 1; i > 0; i-- ) { - X[ 0 ][ i - 1 ] = silk_RSHIFT( X[ 0 ][ i - 1 ], 1 ); - X[ 0 ][ i ] -= X[ 0 ][ i - 1 ]; - } - X[ 0 ][ 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[ 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 ) ); - } - - return( ret ); -} - -/**************************/ -/* Noise level estimation */ -/**************************/ -static 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++; -} |