diff options
Diffstat (limited to 'external/opus-1.1.4/silk/float/prefilter_FLP.c')
| -rw-r--r-- | external/opus-1.1.4/silk/float/prefilter_FLP.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/external/opus-1.1.4/silk/float/prefilter_FLP.c b/external/opus-1.1.4/silk/float/prefilter_FLP.c new file mode 100644 index 0000000..8bc32fb --- /dev/null +++ b/external/opus-1.1.4/silk/float/prefilter_FLP.c @@ -0,0 +1,206 @@ +/*********************************************************************** +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" + +/* +* Prefilter for finding Quantizer input signal +*/ +static OPUS_INLINE void silk_prefilt_FLP( + silk_prefilter_state_FLP *P, /* I/O state */ + silk_float st_res[], /* I */ + silk_float xw[], /* O */ + silk_float *HarmShapeFIR, /* I */ + silk_float Tilt, /* I */ + silk_float LF_MA_shp, /* I */ + silk_float LF_AR_shp, /* I */ + opus_int lag, /* I */ + opus_int length /* I */ +); + +static void silk_warped_LPC_analysis_filter_FLP( + silk_float state[], /* I/O State [order + 1] */ + silk_float res[], /* O Residual signal [length] */ + const silk_float coef[], /* I Coefficients [order] */ + const silk_float input[], /* I Input signal [length] */ + const silk_float lambda, /* I Warping factor */ + const opus_int length, /* I Length of input signal */ + const opus_int order /* I Filter order (even) */ +) +{ + opus_int n, i; + silk_float acc, tmp1, tmp2; + + /* Order must be even */ + silk_assert( ( order & 1 ) == 0 ); + + for( n = 0; n < length; n++ ) { + /* Output of lowpass section */ + tmp2 = state[ 0 ] + lambda * state[ 1 ]; + state[ 0 ] = input[ n ]; + /* Output of allpass section */ + tmp1 = state[ 1 ] + lambda * ( state[ 2 ] - tmp2 ); + state[ 1 ] = tmp2; + acc = coef[ 0 ] * tmp2; + /* Loop over allpass sections */ + for( i = 2; i < order; i += 2 ) { + /* Output of allpass section */ + tmp2 = state[ i ] + lambda * ( state[ i + 1 ] - tmp1 ); + state[ i ] = tmp1; + acc += coef[ i - 1 ] * tmp1; + /* Output of allpass section */ + tmp1 = state[ i + 1 ] + lambda * ( state[ i + 2 ] - tmp2 ); + state[ i + 1 ] = tmp2; + acc += coef[ i ] * tmp2; + } + state[ order ] = tmp1; + acc += coef[ order - 1 ] * tmp1; + res[ n ] = input[ n ] - acc; + } +} + +/* +* silk_prefilter. Main prefilter function +*/ +void silk_prefilter_FLP( + silk_encoder_state_FLP *psEnc, /* I/O Encoder state FLP */ + const silk_encoder_control_FLP *psEncCtrl, /* I Encoder control FLP */ + silk_float xw[], /* O Weighted signal */ + const silk_float x[] /* I Speech signal */ +) +{ + silk_prefilter_state_FLP *P = &psEnc->sPrefilt; + opus_int j, k, lag; + silk_float HarmShapeGain, Tilt, LF_MA_shp, LF_AR_shp; + silk_float B[ 2 ]; + const silk_float *AR1_shp; + const silk_float *px; + silk_float *pxw; + silk_float HarmShapeFIR[ 3 ]; + silk_float st_res[ MAX_SUB_FRAME_LENGTH + MAX_LPC_ORDER ]; + + /* Set up pointers */ + px = x; + pxw = xw; + lag = P->lagPrev; + for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) { + /* Update Variables that change per sub frame */ + if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) { + lag = psEncCtrl->pitchL[ k ]; + } + + /* Noise shape parameters */ + HarmShapeGain = psEncCtrl->HarmShapeGain[ k ] * ( 1.0f - psEncCtrl->HarmBoost[ k ] ); + HarmShapeFIR[ 0 ] = 0.25f * HarmShapeGain; + HarmShapeFIR[ 1 ] = 32767.0f / 65536.0f * HarmShapeGain; + HarmShapeFIR[ 2 ] = 0.25f * HarmShapeGain; + Tilt = psEncCtrl->Tilt[ k ]; + LF_MA_shp = psEncCtrl->LF_MA_shp[ k ]; + LF_AR_shp = psEncCtrl->LF_AR_shp[ k ]; + AR1_shp = &psEncCtrl->AR1[ k * MAX_SHAPE_LPC_ORDER ]; + + /* Short term FIR filtering */ + silk_warped_LPC_analysis_filter_FLP( P->sAR_shp, st_res, AR1_shp, px, + (silk_float)psEnc->sCmn.warping_Q16 / 65536.0f, psEnc->sCmn.subfr_length, psEnc->sCmn.shapingLPCOrder ); + + /* Reduce (mainly) low frequencies during harmonic emphasis */ + B[ 0 ] = psEncCtrl->GainsPre[ k ]; + B[ 1 ] = -psEncCtrl->GainsPre[ k ] * + ( psEncCtrl->HarmBoost[ k ] * HarmShapeGain + INPUT_TILT + psEncCtrl->coding_quality * HIGH_RATE_INPUT_TILT ); + pxw[ 0 ] = B[ 0 ] * st_res[ 0 ] + B[ 1 ] * P->sHarmHP; + for( j = 1; j < psEnc->sCmn.subfr_length; j++ ) { + pxw[ j ] = B[ 0 ] * st_res[ j ] + B[ 1 ] * st_res[ j - 1 ]; + } + P->sHarmHP = st_res[ psEnc->sCmn.subfr_length - 1 ]; + + silk_prefilt_FLP( P, pxw, pxw, HarmShapeFIR, Tilt, LF_MA_shp, LF_AR_shp, lag, psEnc->sCmn.subfr_length ); + + px += psEnc->sCmn.subfr_length; + pxw += psEnc->sCmn.subfr_length; + } + P->lagPrev = psEncCtrl->pitchL[ psEnc->sCmn.nb_subfr - 1 ]; +} + +/* +* Prefilter for finding Quantizer input signal +*/ +static OPUS_INLINE void silk_prefilt_FLP( + silk_prefilter_state_FLP *P, /* I/O state */ + silk_float st_res[], /* I */ + silk_float xw[], /* O */ + silk_float *HarmShapeFIR, /* I */ + silk_float Tilt, /* I */ + silk_float LF_MA_shp, /* I */ + silk_float LF_AR_shp, /* I */ + opus_int lag, /* I */ + opus_int length /* I */ +) +{ + opus_int i; + opus_int idx, LTP_shp_buf_idx; + silk_float n_Tilt, n_LF, n_LTP; + silk_float sLF_AR_shp, sLF_MA_shp; + silk_float *LTP_shp_buf; + + /* To speed up use temp variables instead of using the struct */ + LTP_shp_buf = P->sLTP_shp; + LTP_shp_buf_idx = P->sLTP_shp_buf_idx; + sLF_AR_shp = P->sLF_AR_shp; + sLF_MA_shp = P->sLF_MA_shp; + + for( i = 0; i < length; i++ ) { + if( lag > 0 ) { + silk_assert( HARM_SHAPE_FIR_TAPS == 3 ); + idx = lag + LTP_shp_buf_idx; + n_LTP = LTP_shp_buf[ ( idx - HARM_SHAPE_FIR_TAPS / 2 - 1) & LTP_MASK ] * HarmShapeFIR[ 0 ]; + n_LTP += LTP_shp_buf[ ( idx - HARM_SHAPE_FIR_TAPS / 2 ) & LTP_MASK ] * HarmShapeFIR[ 1 ]; + n_LTP += LTP_shp_buf[ ( idx - HARM_SHAPE_FIR_TAPS / 2 + 1) & LTP_MASK ] * HarmShapeFIR[ 2 ]; + } else { + n_LTP = 0; + } + + n_Tilt = sLF_AR_shp * Tilt; + n_LF = sLF_AR_shp * LF_AR_shp + sLF_MA_shp * LF_MA_shp; + + sLF_AR_shp = st_res[ i ] - n_Tilt; + sLF_MA_shp = sLF_AR_shp - n_LF; + + LTP_shp_buf_idx = ( LTP_shp_buf_idx - 1 ) & LTP_MASK; + LTP_shp_buf[ LTP_shp_buf_idx ] = sLF_MA_shp; + + xw[ i ] = sLF_MA_shp - n_LTP; + } + /* Copy temp variable back to state */ + P->sLF_AR_shp = sLF_AR_shp; + P->sLF_MA_shp = sLF_MA_shp; + P->sLTP_shp_buf_idx = LTP_shp_buf_idx; +} |