diff options
author | hairball <xhairball@gmail.com> | 2014-02-08 03:21:02 +0000 |
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committer | Tim Angus <tim@ngus.net> | 2014-06-17 17:43:38 +0100 |
commit | 35064811c0ac104acddd7777e00bfd9e054c2db6 (patch) | |
tree | 4063389141542093ecc3de47e3999ed099520621 /src/opus-1.1/silk/float/noise_shape_analysis_FLP.c | |
parent | 1778f3fb8cabe7400011c84331018b0ebf6a44b1 (diff) |
Upgrade opus 1.0.2 -> 1.1
Diffstat (limited to 'src/opus-1.1/silk/float/noise_shape_analysis_FLP.c')
-rw-r--r-- | src/opus-1.1/silk/float/noise_shape_analysis_FLP.c | 365 |
1 files changed, 365 insertions, 0 deletions
diff --git a/src/opus-1.1/silk/float/noise_shape_analysis_FLP.c b/src/opus-1.1/silk/float/noise_shape_analysis_FLP.c new file mode 100644 index 00000000..65f6ea58 --- /dev/null +++ b/src/opus-1.1/silk/float/noise_shape_analysis_FLP.c @@ -0,0 +1,365 @@ +/*********************************************************************** +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_FLP.h" +#include "tuning_parameters.h" + +/* Compute gain to make warped filter coefficients have a zero mean log frequency response on a */ +/* non-warped frequency scale. (So that it can be implemented with a minimum-phase monic filter.) */ +/* Note: A monic filter is one with the first coefficient equal to 1.0. In Silk we omit the first */ +/* coefficient in an array of coefficients, for monic filters. */ +static OPUS_INLINE silk_float warped_gain( + const silk_float *coefs, + silk_float lambda, + opus_int order +) { + opus_int i; + silk_float gain; + + lambda = -lambda; + gain = coefs[ order - 1 ]; + for( i = order - 2; i >= 0; i-- ) { + gain = lambda * gain + coefs[ i ]; + } + return (silk_float)( 1.0f / ( 1.0f - lambda * gain ) ); +} + +/* Convert warped filter coefficients to monic pseudo-warped coefficients and limit maximum */ +/* amplitude of monic warped coefficients by using bandwidth expansion on the true coefficients */ +static OPUS_INLINE void warped_true2monic_coefs( + silk_float *coefs_syn, + silk_float *coefs_ana, + silk_float lambda, + silk_float limit, + opus_int order +) { + opus_int i, iter, ind = 0; + silk_float tmp, maxabs, chirp, gain_syn, gain_ana; + + /* Convert to monic coefficients */ + for( i = order - 1; i > 0; i-- ) { + coefs_syn[ i - 1 ] -= lambda * coefs_syn[ i ]; + coefs_ana[ i - 1 ] -= lambda * coefs_ana[ i ]; + } + gain_syn = ( 1.0f - lambda * lambda ) / ( 1.0f + lambda * coefs_syn[ 0 ] ); + gain_ana = ( 1.0f - lambda * lambda ) / ( 1.0f + lambda * coefs_ana[ 0 ] ); + for( i = 0; i < order; i++ ) { + coefs_syn[ i ] *= gain_syn; + coefs_ana[ i ] *= gain_ana; + } + + /* Limit */ + for( iter = 0; iter < 10; iter++ ) { + /* Find maximum absolute value */ + maxabs = -1.0f; + for( i = 0; i < order; i++ ) { + tmp = silk_max( silk_abs_float( coefs_syn[ i ] ), silk_abs_float( coefs_ana[ i ] ) ); + if( tmp > maxabs ) { + maxabs = tmp; + ind = i; + } + } + if( maxabs <= limit ) { + /* Coefficients are within range - done */ + return; + } + + /* Convert back to true warped coefficients */ + for( i = 1; i < order; i++ ) { + coefs_syn[ i - 1 ] += lambda * coefs_syn[ i ]; + coefs_ana[ i - 1 ] += lambda * coefs_ana[ i ]; + } + gain_syn = 1.0f / gain_syn; + gain_ana = 1.0f / gain_ana; + for( i = 0; i < order; i++ ) { + coefs_syn[ i ] *= gain_syn; + coefs_ana[ i ] *= gain_ana; + } + + /* Apply bandwidth expansion */ + chirp = 0.99f - ( 0.8f + 0.1f * iter ) * ( maxabs - limit ) / ( maxabs * ( ind + 1 ) ); + silk_bwexpander_FLP( coefs_syn, order, chirp ); + silk_bwexpander_FLP( coefs_ana, order, chirp ); + + /* Convert to monic warped coefficients */ + for( i = order - 1; i > 0; i-- ) { + coefs_syn[ i - 1 ] -= lambda * coefs_syn[ i ]; + coefs_ana[ i - 1 ] -= lambda * coefs_ana[ i ]; + } + gain_syn = ( 1.0f - lambda * lambda ) / ( 1.0f + lambda * coefs_syn[ 0 ] ); + gain_ana = ( 1.0f - lambda * lambda ) / ( 1.0f + lambda * coefs_ana[ 0 ] ); + for( i = 0; i < order; i++ ) { + coefs_syn[ i ] *= gain_syn; + coefs_ana[ i ] *= gain_ana; + } + } + silk_assert( 0 ); +} + +/* Compute noise shaping coefficients and initial gain values */ +void silk_noise_shape_analysis_FLP( + silk_encoder_state_FLP *psEnc, /* I/O Encoder state FLP */ + silk_encoder_control_FLP *psEncCtrl, /* I/O Encoder control FLP */ + const silk_float *pitch_res, /* I LPC residual from pitch analysis */ + const silk_float *x /* I Input signal [frame_length + la_shape] */ +) +{ + silk_shape_state_FLP *psShapeSt = &psEnc->sShape; + opus_int k, nSamples; + silk_float SNR_adj_dB, HarmBoost, HarmShapeGain, Tilt; + silk_float nrg, pre_nrg, log_energy, log_energy_prev, energy_variation; + silk_float delta, BWExp1, BWExp2, gain_mult, gain_add, strength, b, warping; + silk_float x_windowed[ SHAPE_LPC_WIN_MAX ]; + silk_float auto_corr[ MAX_SHAPE_LPC_ORDER + 1 ]; + const silk_float *x_ptr, *pitch_res_ptr; + + /* Point to start of first LPC analysis block */ + x_ptr = x - psEnc->sCmn.la_shape; + + /****************/ + /* GAIN CONTROL */ + /****************/ + SNR_adj_dB = psEnc->sCmn.SNR_dB_Q7 * ( 1 / 128.0f ); + + /* Input quality is the average of the quality in the lowest two VAD bands */ + psEncCtrl->input_quality = 0.5f * ( psEnc->sCmn.input_quality_bands_Q15[ 0 ] + psEnc->sCmn.input_quality_bands_Q15[ 1 ] ) * ( 1.0f / 32768.0f ); + + /* Coding quality level, between 0.0 and 1.0 */ + psEncCtrl->coding_quality = silk_sigmoid( 0.25f * ( SNR_adj_dB - 20.0f ) ); + + if( psEnc->sCmn.useCBR == 0 ) { + /* Reduce coding SNR during low speech activity */ + b = 1.0f - psEnc->sCmn.speech_activity_Q8 * ( 1.0f / 256.0f ); + SNR_adj_dB -= BG_SNR_DECR_dB * psEncCtrl->coding_quality * ( 0.5f + 0.5f * psEncCtrl->input_quality ) * b * b; + } + + if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) { + /* Reduce gains for periodic signals */ + SNR_adj_dB += HARM_SNR_INCR_dB * psEnc->LTPCorr; + } else { + /* For unvoiced signals and low-quality input, adjust the quality slower than SNR_dB setting */ + SNR_adj_dB += ( -0.4f * psEnc->sCmn.SNR_dB_Q7 * ( 1 / 128.0f ) + 6.0f ) * ( 1.0f - psEncCtrl->input_quality ); + } + + /*************************/ + /* SPARSENESS PROCESSING */ + /*************************/ + /* Set quantizer offset */ + if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) { + /* Initially set to 0; may be overruled in process_gains(..) */ + psEnc->sCmn.indices.quantOffsetType = 0; + psEncCtrl->sparseness = 0.0f; + } else { + /* Sparseness measure, based on relative fluctuations of energy per 2 milliseconds */ + nSamples = 2 * psEnc->sCmn.fs_kHz; + energy_variation = 0.0f; + log_energy_prev = 0.0f; + pitch_res_ptr = pitch_res; + for( k = 0; k < silk_SMULBB( SUB_FRAME_LENGTH_MS, psEnc->sCmn.nb_subfr ) / 2; k++ ) { + nrg = ( silk_float )nSamples + ( silk_float )silk_energy_FLP( pitch_res_ptr, nSamples ); + log_energy = silk_log2( nrg ); + if( k > 0 ) { + energy_variation += silk_abs_float( log_energy - log_energy_prev ); + } + log_energy_prev = log_energy; + pitch_res_ptr += nSamples; + } + psEncCtrl->sparseness = silk_sigmoid( 0.4f * ( energy_variation - 5.0f ) ); + + /* Set quantization offset depending on sparseness measure */ + if( psEncCtrl->sparseness > SPARSENESS_THRESHOLD_QNT_OFFSET ) { + psEnc->sCmn.indices.quantOffsetType = 0; + } else { + psEnc->sCmn.indices.quantOffsetType = 1; + } + + /* Increase coding SNR for sparse signals */ + SNR_adj_dB += SPARSE_SNR_INCR_dB * ( psEncCtrl->sparseness - 0.5f ); + } + + /*******************************/ + /* Control bandwidth expansion */ + /*******************************/ + /* More BWE for signals with high prediction gain */ + strength = FIND_PITCH_WHITE_NOISE_FRACTION * psEncCtrl->predGain; /* between 0.0 and 1.0 */ + BWExp1 = BWExp2 = BANDWIDTH_EXPANSION / ( 1.0f + strength * strength ); + delta = LOW_RATE_BANDWIDTH_EXPANSION_DELTA * ( 1.0f - 0.75f * psEncCtrl->coding_quality ); + BWExp1 -= delta; + BWExp2 += delta; + /* BWExp1 will be applied after BWExp2, so make it relative */ + BWExp1 /= BWExp2; + + if( psEnc->sCmn.warping_Q16 > 0 ) { + /* Slightly more warping in analysis will move quantization noise up in frequency, where it's better masked */ + warping = (silk_float)psEnc->sCmn.warping_Q16 / 65536.0f + 0.01f * psEncCtrl->coding_quality; + } else { + warping = 0.0f; + } + + /********************************************/ + /* Compute noise shaping AR coefs and gains */ + /********************************************/ + for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) { + /* Apply window: sine slope followed by flat part followed by cosine slope */ + opus_int shift, slope_part, flat_part; + flat_part = psEnc->sCmn.fs_kHz * 3; + slope_part = ( psEnc->sCmn.shapeWinLength - flat_part ) / 2; + + silk_apply_sine_window_FLP( x_windowed, x_ptr, 1, slope_part ); + shift = slope_part; + silk_memcpy( x_windowed + shift, x_ptr + shift, flat_part * sizeof(silk_float) ); + shift += flat_part; + silk_apply_sine_window_FLP( x_windowed + shift, x_ptr + shift, 2, slope_part ); + + /* Update pointer: next LPC analysis block */ + x_ptr += psEnc->sCmn.subfr_length; + + if( psEnc->sCmn.warping_Q16 > 0 ) { + /* Calculate warped auto correlation */ + silk_warped_autocorrelation_FLP( auto_corr, x_windowed, warping, + psEnc->sCmn.shapeWinLength, psEnc->sCmn.shapingLPCOrder ); + } else { + /* Calculate regular auto correlation */ + silk_autocorrelation_FLP( auto_corr, x_windowed, psEnc->sCmn.shapeWinLength, psEnc->sCmn.shapingLPCOrder + 1 ); + } + + /* Add white noise, as a fraction of energy */ + auto_corr[ 0 ] += auto_corr[ 0 ] * SHAPE_WHITE_NOISE_FRACTION; + + /* Convert correlations to prediction coefficients, and compute residual energy */ + nrg = silk_levinsondurbin_FLP( &psEncCtrl->AR2[ k * MAX_SHAPE_LPC_ORDER ], auto_corr, psEnc->sCmn.shapingLPCOrder ); + psEncCtrl->Gains[ k ] = ( silk_float )sqrt( nrg ); + + if( psEnc->sCmn.warping_Q16 > 0 ) { + /* Adjust gain for warping */ + psEncCtrl->Gains[ k ] *= warped_gain( &psEncCtrl->AR2[ k * MAX_SHAPE_LPC_ORDER ], warping, psEnc->sCmn.shapingLPCOrder ); + } + + /* Bandwidth expansion for synthesis filter shaping */ + silk_bwexpander_FLP( &psEncCtrl->AR2[ k * MAX_SHAPE_LPC_ORDER ], psEnc->sCmn.shapingLPCOrder, BWExp2 ); + + /* Compute noise shaping filter coefficients */ + silk_memcpy( + &psEncCtrl->AR1[ k * MAX_SHAPE_LPC_ORDER ], + &psEncCtrl->AR2[ k * MAX_SHAPE_LPC_ORDER ], + psEnc->sCmn.shapingLPCOrder * sizeof( silk_float ) ); + + /* Bandwidth expansion for analysis filter shaping */ + silk_bwexpander_FLP( &psEncCtrl->AR1[ k * MAX_SHAPE_LPC_ORDER ], psEnc->sCmn.shapingLPCOrder, BWExp1 ); + + /* Ratio of prediction gains, in energy domain */ + pre_nrg = silk_LPC_inverse_pred_gain_FLP( &psEncCtrl->AR2[ k * MAX_SHAPE_LPC_ORDER ], psEnc->sCmn.shapingLPCOrder ); + nrg = silk_LPC_inverse_pred_gain_FLP( &psEncCtrl->AR1[ k * MAX_SHAPE_LPC_ORDER ], psEnc->sCmn.shapingLPCOrder ); + psEncCtrl->GainsPre[ k ] = 1.0f - 0.7f * ( 1.0f - pre_nrg / nrg ); + + /* Convert to monic warped prediction coefficients and limit absolute values */ + warped_true2monic_coefs( &psEncCtrl->AR2[ k * MAX_SHAPE_LPC_ORDER ], &psEncCtrl->AR1[ k * MAX_SHAPE_LPC_ORDER ], + warping, 3.999f, psEnc->sCmn.shapingLPCOrder ); + } + + /*****************/ + /* Gain tweaking */ + /*****************/ + /* Increase gains during low speech activity */ + gain_mult = (silk_float)pow( 2.0f, -0.16f * SNR_adj_dB ); + gain_add = (silk_float)pow( 2.0f, 0.16f * MIN_QGAIN_DB ); + for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) { + psEncCtrl->Gains[ k ] *= gain_mult; + psEncCtrl->Gains[ k ] += gain_add; + } + + gain_mult = 1.0f + INPUT_TILT + psEncCtrl->coding_quality * HIGH_RATE_INPUT_TILT; + for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) { + psEncCtrl->GainsPre[ k ] *= gain_mult; + } + + /************************************************/ + /* Control low-frequency shaping and noise tilt */ + /************************************************/ + /* Less low frequency shaping for noisy inputs */ + strength = LOW_FREQ_SHAPING * ( 1.0f + LOW_QUALITY_LOW_FREQ_SHAPING_DECR * ( psEnc->sCmn.input_quality_bands_Q15[ 0 ] * ( 1.0f / 32768.0f ) - 1.0f ) ); + strength *= psEnc->sCmn.speech_activity_Q8 * ( 1.0f / 256.0f ); + if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) { + /* Reduce low frequencies quantization noise for periodic signals, depending on pitch lag */ + /*f = 400; freqz([1, -0.98 + 2e-4 * f], [1, -0.97 + 7e-4 * f], 2^12, Fs); axis([0, 1000, -10, 1])*/ + for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) { + b = 0.2f / psEnc->sCmn.fs_kHz + 3.0f / psEncCtrl->pitchL[ k ]; + psEncCtrl->LF_MA_shp[ k ] = -1.0f + b; + psEncCtrl->LF_AR_shp[ k ] = 1.0f - b - b * strength; + } + Tilt = - HP_NOISE_COEF - + (1 - HP_NOISE_COEF) * HARM_HP_NOISE_COEF * psEnc->sCmn.speech_activity_Q8 * ( 1.0f / 256.0f ); + } else { + b = 1.3f / psEnc->sCmn.fs_kHz; + psEncCtrl->LF_MA_shp[ 0 ] = -1.0f + b; + psEncCtrl->LF_AR_shp[ 0 ] = 1.0f - b - b * strength * 0.6f; + for( k = 1; k < psEnc->sCmn.nb_subfr; k++ ) { + psEncCtrl->LF_MA_shp[ k ] = psEncCtrl->LF_MA_shp[ 0 ]; + psEncCtrl->LF_AR_shp[ k ] = psEncCtrl->LF_AR_shp[ 0 ]; + } + Tilt = -HP_NOISE_COEF; + } + + /****************************/ + /* HARMONIC SHAPING CONTROL */ + /****************************/ + /* Control boosting of harmonic frequencies */ + HarmBoost = LOW_RATE_HARMONIC_BOOST * ( 1.0f - psEncCtrl->coding_quality ) * psEnc->LTPCorr; + + /* More harmonic boost for noisy input signals */ + HarmBoost += LOW_INPUT_QUALITY_HARMONIC_BOOST * ( 1.0f - psEncCtrl->input_quality ); + + if( USE_HARM_SHAPING && psEnc->sCmn.indices.signalType == TYPE_VOICED ) { + /* Harmonic noise shaping */ + HarmShapeGain = HARMONIC_SHAPING; + + /* More harmonic noise shaping for high bitrates or noisy input */ + HarmShapeGain += HIGH_RATE_OR_LOW_QUALITY_HARMONIC_SHAPING * + ( 1.0f - ( 1.0f - psEncCtrl->coding_quality ) * psEncCtrl->input_quality ); + + /* Less harmonic noise shaping for less periodic signals */ + HarmShapeGain *= ( silk_float )sqrt( psEnc->LTPCorr ); + } else { + HarmShapeGain = 0.0f; + } + + /*************************/ + /* Smooth over subframes */ + /*************************/ + for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) { + psShapeSt->HarmBoost_smth += SUBFR_SMTH_COEF * ( HarmBoost - psShapeSt->HarmBoost_smth ); + psEncCtrl->HarmBoost[ k ] = psShapeSt->HarmBoost_smth; + psShapeSt->HarmShapeGain_smth += SUBFR_SMTH_COEF * ( HarmShapeGain - psShapeSt->HarmShapeGain_smth ); + psEncCtrl->HarmShapeGain[ k ] = psShapeSt->HarmShapeGain_smth; + psShapeSt->Tilt_smth += SUBFR_SMTH_COEF * ( Tilt - psShapeSt->Tilt_smth ); + psEncCtrl->Tilt[ k ] = psShapeSt->Tilt_smth; + } +} |