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noise_shape_analysis_FIX.c (20438B)


      1 /***********************************************************************
      2 Copyright (c) 2006-2011, Skype Limited. All rights reserved.
      3 Redistribution and use in source and binary forms, with or without
      4 modification, are permitted provided that the following conditions
      5 are met:
      6 - Redistributions of source code must retain the above copyright notice,
      7 this list of conditions and the following disclaimer.
      8 - Redistributions in binary form must reproduce the above copyright
      9 notice, this list of conditions and the following disclaimer in the
     10 documentation and/or other materials provided with the distribution.
     11 - Neither the name of Internet Society, IETF or IETF Trust, nor the
     12 names of specific contributors, may be used to endorse or promote
     13 products derived from this software without specific prior written
     14 permission.
     15 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
     16 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     17 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     18 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
     19 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     20 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     21 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     22 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     23 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     24 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     25 POSSIBILITY OF SUCH DAMAGE.
     26 ***********************************************************************/
     27 
     28 #ifdef HAVE_CONFIG_H
     29 #include "config.h"
     30 #endif
     31 
     32 #include "main_FIX.h"
     33 #include "stack_alloc.h"
     34 #include "tuning_parameters.h"
     35 
     36 /* Compute gain to make warped filter coefficients have a zero mean log frequency response on a   */
     37 /* non-warped frequency scale. (So that it can be implemented with a minimum-phase monic filter.) */
     38 /* Note: A monic filter is one with the first coefficient equal to 1.0. In Silk we omit the first */
     39 /* coefficient in an array of coefficients, for monic filters.                                    */
     40 static OPUS_INLINE opus_int32 warped_gain( /* gain in Q16*/
     41    const opus_int32     *coefs_Q24,
     42    opus_int             lambda_Q16,
     43    opus_int             order
     44 ) {
     45    opus_int   i;
     46    opus_int32 gain_Q24;
     47 
     48    lambda_Q16 = -lambda_Q16;
     49    gain_Q24 = coefs_Q24[ order - 1 ];
     50    for( i = order - 2; i >= 0; i-- ) {
     51        gain_Q24 = silk_SMLAWB( coefs_Q24[ i ], gain_Q24, lambda_Q16 );
     52    }
     53    gain_Q24  = silk_SMLAWB( SILK_FIX_CONST( 1.0, 24 ), gain_Q24, -lambda_Q16 );
     54    return silk_INVERSE32_varQ( gain_Q24, 40 );
     55 }
     56 
     57 /* Convert warped filter coefficients to monic pseudo-warped coefficients and limit maximum     */
     58 /* amplitude of monic warped coefficients by using bandwidth expansion on the true coefficients */
     59 static OPUS_INLINE void limit_warped_coefs(
     60    opus_int32           *coefs_Q24,
     61    opus_int             lambda_Q16,
     62    opus_int32           limit_Q24,
     63    opus_int             order
     64 ) {
     65    opus_int   i, iter, ind = 0;
     66    opus_int32 tmp, maxabs_Q24, chirp_Q16, gain_Q16;
     67    opus_int32 nom_Q16, den_Q24;
     68    opus_int32 limit_Q20, maxabs_Q20;
     69 
     70    /* Convert to monic coefficients */
     71    lambda_Q16 = -lambda_Q16;
     72    for( i = order - 1; i > 0; i-- ) {
     73        coefs_Q24[ i - 1 ] = silk_SMLAWB( coefs_Q24[ i - 1 ], coefs_Q24[ i ], lambda_Q16 );
     74    }
     75    lambda_Q16 = -lambda_Q16;
     76    nom_Q16  = silk_SMLAWB( SILK_FIX_CONST( 1.0, 16 ), -(opus_int32)lambda_Q16, lambda_Q16 );
     77    den_Q24  = silk_SMLAWB( SILK_FIX_CONST( 1.0, 24 ), coefs_Q24[ 0 ], lambda_Q16 );
     78    gain_Q16 = silk_DIV32_varQ( nom_Q16, den_Q24, 24 );
     79    for( i = 0; i < order; i++ ) {
     80        coefs_Q24[ i ] = silk_SMULWW( gain_Q16, coefs_Q24[ i ] );
     81    }
     82    limit_Q20 = silk_RSHIFT(limit_Q24, 4);
     83    for( iter = 0; iter < 10; iter++ ) {
     84        /* Find maximum absolute value */
     85        maxabs_Q24 = -1;
     86        for( i = 0; i < order; i++ ) {
     87            tmp = silk_abs_int32( coefs_Q24[ i ] );
     88            if( tmp > maxabs_Q24 ) {
     89                maxabs_Q24 = tmp;
     90                ind = i;
     91            }
     92        }
     93        /* Use Q20 to avoid any overflow when multiplying by (ind + 1) later. */
     94        maxabs_Q20 = silk_RSHIFT(maxabs_Q24, 4);
     95        if( maxabs_Q20 <= limit_Q20 ) {
     96            /* Coefficients are within range - done */
     97            return;
     98        }
     99 
    100        /* Convert back to true warped coefficients */
    101        for( i = 1; i < order; i++ ) {
    102            coefs_Q24[ i - 1 ] = silk_SMLAWB( coefs_Q24[ i - 1 ], coefs_Q24[ i ], lambda_Q16 );
    103        }
    104        gain_Q16 = silk_INVERSE32_varQ( gain_Q16, 32 );
    105        for( i = 0; i < order; i++ ) {
    106            coefs_Q24[ i ] = silk_SMULWW( gain_Q16, coefs_Q24[ i ] );
    107        }
    108 
    109        /* Apply bandwidth expansion */
    110        chirp_Q16 = SILK_FIX_CONST( 0.99, 16 ) - silk_DIV32_varQ(
    111            silk_SMULWB( maxabs_Q20 - limit_Q20, silk_SMLABB( SILK_FIX_CONST( 0.8, 10 ), SILK_FIX_CONST( 0.1, 10 ), iter ) ),
    112            silk_MUL( maxabs_Q20, ind + 1 ), 22 );
    113        silk_bwexpander_32( coefs_Q24, order, chirp_Q16 );
    114 
    115        /* Convert to monic warped coefficients */
    116        lambda_Q16 = -lambda_Q16;
    117        for( i = order - 1; i > 0; i-- ) {
    118            coefs_Q24[ i - 1 ] = silk_SMLAWB( coefs_Q24[ i - 1 ], coefs_Q24[ i ], lambda_Q16 );
    119        }
    120        lambda_Q16 = -lambda_Q16;
    121        nom_Q16  = silk_SMLAWB( SILK_FIX_CONST( 1.0, 16 ), -(opus_int32)lambda_Q16,        lambda_Q16 );
    122        den_Q24  = silk_SMLAWB( SILK_FIX_CONST( 1.0, 24 ), coefs_Q24[ 0 ], lambda_Q16 );
    123        gain_Q16 = silk_DIV32_varQ( nom_Q16, den_Q24, 24 );
    124        for( i = 0; i < order; i++ ) {
    125            coefs_Q24[ i ] = silk_SMULWW( gain_Q16, coefs_Q24[ i ] );
    126        }
    127    }
    128    silk_assert( 0 );
    129 }
    130 
    131 /**************************************************************/
    132 /* Compute noise shaping coefficients and initial gain values */
    133 /**************************************************************/
    134 void silk_noise_shape_analysis_FIX(
    135    silk_encoder_state_FIX          *psEnc,                                 /* I/O  Encoder state FIX                                                           */
    136    silk_encoder_control_FIX        *psEncCtrl,                             /* I/O  Encoder control FIX                                                         */
    137    const opus_int16                *pitch_res,                             /* I    LPC residual from pitch analysis                                            */
    138    const opus_int16                *x,                                     /* I    Input signal [ frame_length + la_shape ]                                    */
    139    int                              arch                                   /* I    Run-time architecture                                                       */
    140 )
    141 {
    142    silk_shape_state_FIX *psShapeSt = &psEnc->sShape;
    143    opus_int     k, i, nSamples, nSegs, Qnrg, b_Q14, warping_Q16, scale = 0;
    144    opus_int32   SNR_adj_dB_Q7, HarmShapeGain_Q16, Tilt_Q16, tmp32;
    145    opus_int32   nrg, log_energy_Q7, log_energy_prev_Q7, energy_variation_Q7;
    146    opus_int32   BWExp_Q16, gain_mult_Q16, gain_add_Q16, strength_Q16, b_Q8;
    147    opus_int32   auto_corr[     MAX_SHAPE_LPC_ORDER + 1 ];
    148    opus_int32   refl_coef_Q16[ MAX_SHAPE_LPC_ORDER ];
    149    opus_int32   AR_Q24[       MAX_SHAPE_LPC_ORDER ];
    150    VARDECL( opus_int16, x_windowed );
    151    const opus_int16 *x_ptr, *pitch_res_ptr;
    152    SAVE_STACK;
    153 
    154    /* Point to start of first LPC analysis block */
    155    x_ptr = x - psEnc->sCmn.la_shape;
    156 
    157    /****************/
    158    /* GAIN CONTROL */
    159    /****************/
    160    SNR_adj_dB_Q7 = psEnc->sCmn.SNR_dB_Q7;
    161 
    162    /* Input quality is the average of the quality in the lowest two VAD bands */
    163    psEncCtrl->input_quality_Q14 = ( opus_int )silk_RSHIFT( (opus_int32)psEnc->sCmn.input_quality_bands_Q15[ 0 ]
    164        + psEnc->sCmn.input_quality_bands_Q15[ 1 ], 2 );
    165 
    166    /* Coding quality level, between 0.0_Q0 and 1.0_Q0, but in Q14 */
    167    psEncCtrl->coding_quality_Q14 = silk_RSHIFT( silk_sigm_Q15( silk_RSHIFT_ROUND( SNR_adj_dB_Q7 -
    168        SILK_FIX_CONST( 20.0, 7 ), 4 ) ), 1 );
    169 
    170    /* Reduce coding SNR during low speech activity */
    171    if( psEnc->sCmn.useCBR == 0 ) {
    172        b_Q8 = SILK_FIX_CONST( 1.0, 8 ) - psEnc->sCmn.speech_activity_Q8;
    173        b_Q8 = silk_SMULWB( silk_LSHIFT( b_Q8, 8 ), b_Q8 );
    174        SNR_adj_dB_Q7 = silk_SMLAWB( SNR_adj_dB_Q7,
    175            silk_SMULBB( SILK_FIX_CONST( -BG_SNR_DECR_dB, 7 ) >> ( 4 + 1 ), b_Q8 ),                                       /* Q11*/
    176            silk_SMULWB( SILK_FIX_CONST( 1.0, 14 ) + psEncCtrl->input_quality_Q14, psEncCtrl->coding_quality_Q14 ) );     /* Q12*/
    177    }
    178 
    179    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
    180        /* Reduce gains for periodic signals */
    181        SNR_adj_dB_Q7 = silk_SMLAWB( SNR_adj_dB_Q7, SILK_FIX_CONST( HARM_SNR_INCR_dB, 8 ), psEnc->LTPCorr_Q15 );
    182    } else {
    183        /* For unvoiced signals and low-quality input, adjust the quality slower than SNR_dB setting */
    184        SNR_adj_dB_Q7 = silk_SMLAWB( SNR_adj_dB_Q7,
    185            silk_SMLAWB( SILK_FIX_CONST( 6.0, 9 ), -SILK_FIX_CONST( 0.4, 18 ), psEnc->sCmn.SNR_dB_Q7 ),
    186            SILK_FIX_CONST( 1.0, 14 ) - psEncCtrl->input_quality_Q14 );
    187    }
    188 
    189    /*************************/
    190    /* SPARSENESS PROCESSING */
    191    /*************************/
    192    /* Set quantizer offset */
    193    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
    194        /* Initially set to 0; may be overruled in process_gains(..) */
    195        psEnc->sCmn.indices.quantOffsetType = 0;
    196    } else {
    197        /* Sparseness measure, based on relative fluctuations of energy per 2 milliseconds */
    198        nSamples = silk_LSHIFT( psEnc->sCmn.fs_kHz, 1 );
    199        energy_variation_Q7 = 0;
    200        log_energy_prev_Q7  = 0;
    201        pitch_res_ptr = pitch_res;
    202        nSegs = silk_SMULBB( SUB_FRAME_LENGTH_MS, psEnc->sCmn.nb_subfr ) / 2;
    203        for( k = 0; k < nSegs; k++ ) {
    204            silk_sum_sqr_shift( &nrg, &scale, pitch_res_ptr, nSamples );
    205            nrg += silk_RSHIFT( nSamples, scale );           /* Q(-scale)*/
    206 
    207            log_energy_Q7 = silk_lin2log( nrg );
    208            if( k > 0 ) {
    209                energy_variation_Q7 += silk_abs( log_energy_Q7 - log_energy_prev_Q7 );
    210            }
    211            log_energy_prev_Q7 = log_energy_Q7;
    212            pitch_res_ptr += nSamples;
    213        }
    214 
    215        /* Set quantization offset depending on sparseness measure */
    216        if( energy_variation_Q7 > SILK_FIX_CONST( ENERGY_VARIATION_THRESHOLD_QNT_OFFSET, 7 ) * (nSegs-1) ) {
    217            psEnc->sCmn.indices.quantOffsetType = 0;
    218        } else {
    219            psEnc->sCmn.indices.quantOffsetType = 1;
    220        }
    221    }
    222 
    223    /*******************************/
    224    /* Control bandwidth expansion */
    225    /*******************************/
    226    /* More BWE for signals with high prediction gain */
    227    strength_Q16 = silk_SMULWB( psEncCtrl->predGain_Q16, SILK_FIX_CONST( FIND_PITCH_WHITE_NOISE_FRACTION, 16 ) );
    228    BWExp_Q16 = silk_DIV32_varQ( SILK_FIX_CONST( BANDWIDTH_EXPANSION, 16 ),
    229        silk_SMLAWW( SILK_FIX_CONST( 1.0, 16 ), strength_Q16, strength_Q16 ), 16 );
    230 
    231    if( psEnc->sCmn.warping_Q16 > 0 ) {
    232        /* Slightly more warping in analysis will move quantization noise up in frequency, where it's better masked */
    233        warping_Q16 = silk_SMLAWB( psEnc->sCmn.warping_Q16, (opus_int32)psEncCtrl->coding_quality_Q14, SILK_FIX_CONST( 0.01, 18 ) );
    234    } else {
    235        warping_Q16 = 0;
    236    }
    237 
    238    /********************************************/
    239    /* Compute noise shaping AR coefs and gains */
    240    /********************************************/
    241    ALLOC( x_windowed, psEnc->sCmn.shapeWinLength, opus_int16 );
    242    for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
    243        /* Apply window: sine slope followed by flat part followed by cosine slope */
    244        opus_int shift, slope_part, flat_part;
    245        flat_part = psEnc->sCmn.fs_kHz * 3;
    246        slope_part = silk_RSHIFT( psEnc->sCmn.shapeWinLength - flat_part, 1 );
    247 
    248        silk_apply_sine_window( x_windowed, x_ptr, 1, slope_part );
    249        shift = slope_part;
    250        silk_memcpy( x_windowed + shift, x_ptr + shift, flat_part * sizeof(opus_int16) );
    251        shift += flat_part;
    252        silk_apply_sine_window( x_windowed + shift, x_ptr + shift, 2, slope_part );
    253 
    254        /* Update pointer: next LPC analysis block */
    255        x_ptr += psEnc->sCmn.subfr_length;
    256 
    257        if( psEnc->sCmn.warping_Q16 > 0 ) {
    258            /* Calculate warped auto correlation */
    259            silk_warped_autocorrelation_FIX( auto_corr, &scale, x_windowed, warping_Q16, psEnc->sCmn.shapeWinLength, psEnc->sCmn.shapingLPCOrder, arch );
    260        } else {
    261            /* Calculate regular auto correlation */
    262            silk_autocorr( auto_corr, &scale, x_windowed, psEnc->sCmn.shapeWinLength, psEnc->sCmn.shapingLPCOrder + 1, arch );
    263        }
    264 
    265        /* Add white noise, as a fraction of energy */
    266        auto_corr[0] = silk_ADD32( auto_corr[0], silk_max_32( silk_SMULWB( silk_RSHIFT( auto_corr[ 0 ], 4 ),
    267            SILK_FIX_CONST( SHAPE_WHITE_NOISE_FRACTION, 20 ) ), 1 ) );
    268 
    269        /* Calculate the reflection coefficients using schur */
    270        nrg = silk_schur64( refl_coef_Q16, auto_corr, psEnc->sCmn.shapingLPCOrder );
    271        silk_assert( nrg >= 0 );
    272 
    273        /* Convert reflection coefficients to prediction coefficients */
    274        silk_k2a_Q16( AR_Q24, refl_coef_Q16, psEnc->sCmn.shapingLPCOrder );
    275 
    276        Qnrg = -scale;          /* range: -12...30*/
    277        silk_assert( Qnrg >= -12 );
    278        silk_assert( Qnrg <=  30 );
    279 
    280        /* Make sure that Qnrg is an even number */
    281        if( Qnrg & 1 ) {
    282            Qnrg -= 1;
    283            nrg >>= 1;
    284        }
    285 
    286        tmp32 = silk_SQRT_APPROX( nrg );
    287        Qnrg >>= 1;             /* range: -6...15*/
    288 
    289        psEncCtrl->Gains_Q16[ k ] = silk_LSHIFT_SAT32( tmp32, 16 - Qnrg );
    290 
    291        if( psEnc->sCmn.warping_Q16 > 0 ) {
    292            /* Adjust gain for warping */
    293            gain_mult_Q16 = warped_gain( AR_Q24, warping_Q16, psEnc->sCmn.shapingLPCOrder );
    294            silk_assert( psEncCtrl->Gains_Q16[ k ] > 0 );
    295            if( psEncCtrl->Gains_Q16[ k ] < SILK_FIX_CONST( 0.25, 16 ) ) {
    296                psEncCtrl->Gains_Q16[ k ] = silk_SMULWW( psEncCtrl->Gains_Q16[ k ], gain_mult_Q16 );
    297            } else {
    298                psEncCtrl->Gains_Q16[ k ] = silk_SMULWW( silk_RSHIFT_ROUND( psEncCtrl->Gains_Q16[ k ], 1 ), gain_mult_Q16 );
    299                if ( psEncCtrl->Gains_Q16[ k ] >= ( silk_int32_MAX >> 1 ) ) {
    300                    psEncCtrl->Gains_Q16[ k ] = silk_int32_MAX;
    301                } else {
    302                    psEncCtrl->Gains_Q16[ k ] = silk_LSHIFT32( psEncCtrl->Gains_Q16[ k ], 1 );
    303                }
    304            }
    305            silk_assert( psEncCtrl->Gains_Q16[ k ] > 0 );
    306        }
    307 
    308        /* Bandwidth expansion */
    309        silk_bwexpander_32( AR_Q24, psEnc->sCmn.shapingLPCOrder, BWExp_Q16 );
    310 
    311        if( psEnc->sCmn.warping_Q16 > 0 ) {
    312            /* Convert to monic warped prediction coefficients and limit absolute values */
    313            limit_warped_coefs( AR_Q24, warping_Q16, SILK_FIX_CONST( 3.999, 24 ), psEnc->sCmn.shapingLPCOrder );
    314 
    315            /* Convert from Q24 to Q13 and store in int16 */
    316            for( i = 0; i < psEnc->sCmn.shapingLPCOrder; i++ ) {
    317                psEncCtrl->AR_Q13[ k * MAX_SHAPE_LPC_ORDER + i ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( AR_Q24[ i ], 11 ) );
    318            }
    319        } else {
    320            silk_LPC_fit( &psEncCtrl->AR_Q13[ k * MAX_SHAPE_LPC_ORDER ], AR_Q24, 13, 24, psEnc->sCmn.shapingLPCOrder );
    321        }
    322    }
    323 
    324    /*****************/
    325    /* Gain tweaking */
    326    /*****************/
    327    /* Increase gains during low speech activity and put lower limit on gains */
    328    gain_mult_Q16 = silk_log2lin( -silk_SMLAWB( -SILK_FIX_CONST( 16.0, 7 ), SNR_adj_dB_Q7, SILK_FIX_CONST( 0.16, 16 ) ) );
    329    gain_add_Q16  = silk_log2lin(  silk_SMLAWB(  SILK_FIX_CONST( 16.0, 7 ), SILK_FIX_CONST( MIN_QGAIN_DB, 7 ), SILK_FIX_CONST( 0.16, 16 ) ) );
    330    silk_assert( gain_mult_Q16 > 0 );
    331    for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
    332        psEncCtrl->Gains_Q16[ k ] = silk_SMULWW( psEncCtrl->Gains_Q16[ k ], gain_mult_Q16 );
    333        silk_assert( psEncCtrl->Gains_Q16[ k ] >= 0 );
    334        psEncCtrl->Gains_Q16[ k ] = silk_ADD_POS_SAT32( psEncCtrl->Gains_Q16[ k ], gain_add_Q16 );
    335    }
    336 
    337 
    338    /************************************************/
    339    /* Control low-frequency shaping and noise tilt */
    340    /************************************************/
    341    /* Less low frequency shaping for noisy inputs */
    342    strength_Q16 = silk_MUL( SILK_FIX_CONST( LOW_FREQ_SHAPING, 4 ), silk_SMLAWB( SILK_FIX_CONST( 1.0, 12 ),
    343        SILK_FIX_CONST( LOW_QUALITY_LOW_FREQ_SHAPING_DECR, 13 ), psEnc->sCmn.input_quality_bands_Q15[ 0 ] - SILK_FIX_CONST( 1.0, 15 ) ) );
    344    strength_Q16 = silk_RSHIFT( silk_MUL( strength_Q16, psEnc->sCmn.speech_activity_Q8 ), 8 );
    345    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
    346        /* Reduce low frequencies quantization noise for periodic signals, depending on pitch lag */
    347        /*f = 400; freqz([1, -0.98 + 2e-4 * f], [1, -0.97 + 7e-4 * f], 2^12, Fs); axis([0, 1000, -10, 1])*/
    348        opus_int fs_kHz_inv = silk_DIV32_16( SILK_FIX_CONST( 0.2, 14 ), psEnc->sCmn.fs_kHz );
    349        for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
    350            b_Q14 = fs_kHz_inv + silk_DIV32_16( SILK_FIX_CONST( 3.0, 14 ), psEncCtrl->pitchL[ k ] );
    351            /* Pack two coefficients in one int32 */
    352            psEncCtrl->LF_shp_Q14[ k ]  = silk_LSHIFT( SILK_FIX_CONST( 1.0, 14 ) - b_Q14 - silk_SMULWB( strength_Q16, b_Q14 ), 16 );
    353            psEncCtrl->LF_shp_Q14[ k ] |= (opus_uint16)( b_Q14 - SILK_FIX_CONST( 1.0, 14 ) );
    354        }
    355        silk_assert( SILK_FIX_CONST( HARM_HP_NOISE_COEF, 24 ) < SILK_FIX_CONST( 0.5, 24 ) ); /* Guarantees that second argument to SMULWB() is within range of an opus_int16*/
    356        Tilt_Q16 = - SILK_FIX_CONST( HP_NOISE_COEF, 16 ) -
    357            silk_SMULWB( SILK_FIX_CONST( 1.0, 16 ) - SILK_FIX_CONST( HP_NOISE_COEF, 16 ),
    358                silk_SMULWB( SILK_FIX_CONST( HARM_HP_NOISE_COEF, 24 ), psEnc->sCmn.speech_activity_Q8 ) );
    359    } else {
    360        b_Q14 = silk_DIV32_16( 21299, psEnc->sCmn.fs_kHz ); /* 1.3_Q0 = 21299_Q14*/
    361        /* Pack two coefficients in one int32 */
    362        psEncCtrl->LF_shp_Q14[ 0 ]  = silk_LSHIFT( SILK_FIX_CONST( 1.0, 14 ) - b_Q14 -
    363            silk_SMULWB( strength_Q16, silk_SMULWB( SILK_FIX_CONST( 0.6, 16 ), b_Q14 ) ), 16 );
    364        psEncCtrl->LF_shp_Q14[ 0 ] |= (opus_uint16)( b_Q14 - SILK_FIX_CONST( 1.0, 14 ) );
    365        for( k = 1; k < psEnc->sCmn.nb_subfr; k++ ) {
    366            psEncCtrl->LF_shp_Q14[ k ] = psEncCtrl->LF_shp_Q14[ 0 ];
    367        }
    368        Tilt_Q16 = -SILK_FIX_CONST( HP_NOISE_COEF, 16 );
    369    }
    370 
    371    /****************************/
    372    /* HARMONIC SHAPING CONTROL */
    373    /****************************/
    374    if( USE_HARM_SHAPING && psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
    375        /* More harmonic noise shaping for high bitrates or noisy input */
    376        HarmShapeGain_Q16 = silk_SMLAWB( SILK_FIX_CONST( HARMONIC_SHAPING, 16 ),
    377                SILK_FIX_CONST( 1.0, 16 ) - silk_SMULWB( SILK_FIX_CONST( 1.0, 18 ) - silk_LSHIFT( psEncCtrl->coding_quality_Q14, 4 ),
    378                psEncCtrl->input_quality_Q14 ), SILK_FIX_CONST( HIGH_RATE_OR_LOW_QUALITY_HARMONIC_SHAPING, 16 ) );
    379 
    380        /* Less harmonic noise shaping for less periodic signals */
    381        HarmShapeGain_Q16 = silk_SMULWB( silk_LSHIFT( HarmShapeGain_Q16, 1 ),
    382            silk_SQRT_APPROX( silk_LSHIFT( psEnc->LTPCorr_Q15, 15 ) ) );
    383    } else {
    384        HarmShapeGain_Q16 = 0;
    385    }
    386 
    387    /*************************/
    388    /* Smooth over subframes */
    389    /*************************/
    390    for( k = 0; k < MAX_NB_SUBFR; k++ ) {
    391        psShapeSt->HarmShapeGain_smth_Q16 =
    392            silk_SMLAWB( psShapeSt->HarmShapeGain_smth_Q16, HarmShapeGain_Q16 - psShapeSt->HarmShapeGain_smth_Q16, SILK_FIX_CONST( SUBFR_SMTH_COEF, 16 ) );
    393        psShapeSt->Tilt_smth_Q16 =
    394            silk_SMLAWB( psShapeSt->Tilt_smth_Q16,          Tilt_Q16          - psShapeSt->Tilt_smth_Q16,          SILK_FIX_CONST( SUBFR_SMTH_COEF, 16 ) );
    395 
    396        psEncCtrl->HarmShapeGain_Q14[ k ] = ( opus_int )silk_RSHIFT_ROUND( psShapeSt->HarmShapeGain_smth_Q16, 2 );
    397        psEncCtrl->Tilt_Q14[ k ]          = ( opus_int )silk_RSHIFT_ROUND( psShapeSt->Tilt_smth_Q16,          2 );
    398    }
    399    RESTORE_STACK;
    400 }