1/***********************************************************************
2Copyright (c) 2006-2011, Skype Limited. All rights reserved.
3Redistribution and use in source and binary forms, with or without
4modification, are permitted provided that the following conditions
5are met:
6- Redistributions of source code must retain the above copyright notice,
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8- Redistributions in binary form must reproduce the above copyright
9notice, this list of conditions and the following disclaimer in the
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11- Neither the name of Internet Society, IETF or IETF Trust, nor the
12names of specific contributors, may be used to endorse or promote
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14permission.
15THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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24ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25POSSIBILITY 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.                                    */
40static 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 */
59static OPUS_INLINE void limit_warped_coefs(
60    opus_int32           *coefs_syn_Q24,
61    opus_int32           *coefs_ana_Q24,
62    opus_int             lambda_Q16,
63    opus_int32           limit_Q24,
64    opus_int             order
65) {
66    opus_int   i, iter, ind = 0;
67    opus_int32 tmp, maxabs_Q24, chirp_Q16, gain_syn_Q16, gain_ana_Q16;
68    opus_int32 nom_Q16, den_Q24;
69
70    /* Convert to monic coefficients */
71    lambda_Q16 = -lambda_Q16;
72    for( i = order - 1; i > 0; i-- ) {
73        coefs_syn_Q24[ i - 1 ] = silk_SMLAWB( coefs_syn_Q24[ i - 1 ], coefs_syn_Q24[ i ], lambda_Q16 );
74        coefs_ana_Q24[ i - 1 ] = silk_SMLAWB( coefs_ana_Q24[ i - 1 ], coefs_ana_Q24[ i ], lambda_Q16 );
75    }
76    lambda_Q16 = -lambda_Q16;
77    nom_Q16  = silk_SMLAWB( SILK_FIX_CONST( 1.0, 16 ), -(opus_int32)lambda_Q16,        lambda_Q16 );
78    den_Q24  = silk_SMLAWB( SILK_FIX_CONST( 1.0, 24 ), coefs_syn_Q24[ 0 ], lambda_Q16 );
79    gain_syn_Q16 = silk_DIV32_varQ( nom_Q16, den_Q24, 24 );
80    den_Q24  = silk_SMLAWB( SILK_FIX_CONST( 1.0, 24 ), coefs_ana_Q24[ 0 ], lambda_Q16 );
81    gain_ana_Q16 = silk_DIV32_varQ( nom_Q16, den_Q24, 24 );
82    for( i = 0; i < order; i++ ) {
83        coefs_syn_Q24[ i ] = silk_SMULWW( gain_syn_Q16, coefs_syn_Q24[ i ] );
84        coefs_ana_Q24[ i ] = silk_SMULWW( gain_ana_Q16, coefs_ana_Q24[ i ] );
85    }
86
87    for( iter = 0; iter < 10; iter++ ) {
88        /* Find maximum absolute value */
89        maxabs_Q24 = -1;
90        for( i = 0; i < order; i++ ) {
91            tmp = silk_max( silk_abs_int32( coefs_syn_Q24[ i ] ), silk_abs_int32( coefs_ana_Q24[ i ] ) );
92            if( tmp > maxabs_Q24 ) {
93                maxabs_Q24 = tmp;
94                ind = i;
95            }
96        }
97        if( maxabs_Q24 <= limit_Q24 ) {
98            /* Coefficients are within range - done */
99            return;
100        }
101
102        /* Convert back to true warped coefficients */
103        for( i = 1; i < order; i++ ) {
104            coefs_syn_Q24[ i - 1 ] = silk_SMLAWB( coefs_syn_Q24[ i - 1 ], coefs_syn_Q24[ i ], lambda_Q16 );
105            coefs_ana_Q24[ i - 1 ] = silk_SMLAWB( coefs_ana_Q24[ i - 1 ], coefs_ana_Q24[ i ], lambda_Q16 );
106        }
107        gain_syn_Q16 = silk_INVERSE32_varQ( gain_syn_Q16, 32 );
108        gain_ana_Q16 = silk_INVERSE32_varQ( gain_ana_Q16, 32 );
109        for( i = 0; i < order; i++ ) {
110            coefs_syn_Q24[ i ] = silk_SMULWW( gain_syn_Q16, coefs_syn_Q24[ i ] );
111            coefs_ana_Q24[ i ] = silk_SMULWW( gain_ana_Q16, coefs_ana_Q24[ i ] );
112        }
113
114        /* Apply bandwidth expansion */
115        chirp_Q16 = SILK_FIX_CONST( 0.99, 16 ) - silk_DIV32_varQ(
116            silk_SMULWB( maxabs_Q24 - limit_Q24, silk_SMLABB( SILK_FIX_CONST( 0.8, 10 ), SILK_FIX_CONST( 0.1, 10 ), iter ) ),
117            silk_MUL( maxabs_Q24, ind + 1 ), 22 );
118        silk_bwexpander_32( coefs_syn_Q24, order, chirp_Q16 );
119        silk_bwexpander_32( coefs_ana_Q24, order, chirp_Q16 );
120
121        /* Convert to monic warped coefficients */
122        lambda_Q16 = -lambda_Q16;
123        for( i = order - 1; i > 0; i-- ) {
124            coefs_syn_Q24[ i - 1 ] = silk_SMLAWB( coefs_syn_Q24[ i - 1 ], coefs_syn_Q24[ i ], lambda_Q16 );
125            coefs_ana_Q24[ i - 1 ] = silk_SMLAWB( coefs_ana_Q24[ i - 1 ], coefs_ana_Q24[ i ], lambda_Q16 );
126        }
127        lambda_Q16 = -lambda_Q16;
128        nom_Q16  = silk_SMLAWB( SILK_FIX_CONST( 1.0, 16 ), -(opus_int32)lambda_Q16,        lambda_Q16 );
129        den_Q24  = silk_SMLAWB( SILK_FIX_CONST( 1.0, 24 ), coefs_syn_Q24[ 0 ], lambda_Q16 );
130        gain_syn_Q16 = silk_DIV32_varQ( nom_Q16, den_Q24, 24 );
131        den_Q24  = silk_SMLAWB( SILK_FIX_CONST( 1.0, 24 ), coefs_ana_Q24[ 0 ], lambda_Q16 );
132        gain_ana_Q16 = silk_DIV32_varQ( nom_Q16, den_Q24, 24 );
133        for( i = 0; i < order; i++ ) {
134            coefs_syn_Q24[ i ] = silk_SMULWW( gain_syn_Q16, coefs_syn_Q24[ i ] );
135            coefs_ana_Q24[ i ] = silk_SMULWW( gain_ana_Q16, coefs_ana_Q24[ i ] );
136        }
137    }
138    silk_assert( 0 );
139}
140
141#if defined(MIPSr1_ASM)
142#include "mips/noise_shape_analysis_FIX_mipsr1.h"
143#endif
144
145/**************************************************************/
146/* Compute noise shaping coefficients and initial gain values */
147/**************************************************************/
148#ifndef OVERRIDE_silk_noise_shape_analysis_FIX
149void silk_noise_shape_analysis_FIX(
150    silk_encoder_state_FIX          *psEnc,                                 /* I/O  Encoder state FIX                                                           */
151    silk_encoder_control_FIX        *psEncCtrl,                             /* I/O  Encoder control FIX                                                         */
152    const opus_int16                *pitch_res,                             /* I    LPC residual from pitch analysis                                            */
153    const opus_int16                *x,                                     /* I    Input signal [ frame_length + la_shape ]                                    */
154    int                              arch                                   /* I    Run-time architecture                                                       */
155)
156{
157    silk_shape_state_FIX *psShapeSt = &psEnc->sShape;
158    opus_int     k, i, nSamples, Qnrg, b_Q14, warping_Q16, scale = 0;
159    opus_int32   SNR_adj_dB_Q7, HarmBoost_Q16, HarmShapeGain_Q16, Tilt_Q16, tmp32;
160    opus_int32   nrg, pre_nrg_Q30, log_energy_Q7, log_energy_prev_Q7, energy_variation_Q7;
161    opus_int32   delta_Q16, BWExp1_Q16, BWExp2_Q16, gain_mult_Q16, gain_add_Q16, strength_Q16, b_Q8;
162    opus_int32   auto_corr[     MAX_SHAPE_LPC_ORDER + 1 ];
163    opus_int32   refl_coef_Q16[ MAX_SHAPE_LPC_ORDER ];
164    opus_int32   AR1_Q24[       MAX_SHAPE_LPC_ORDER ];
165    opus_int32   AR2_Q24[       MAX_SHAPE_LPC_ORDER ];
166    VARDECL( opus_int16, x_windowed );
167    const opus_int16 *x_ptr, *pitch_res_ptr;
168    SAVE_STACK;
169
170    /* Point to start of first LPC analysis block */
171    x_ptr = x - psEnc->sCmn.la_shape;
172
173    /****************/
174    /* GAIN CONTROL */
175    /****************/
176    SNR_adj_dB_Q7 = psEnc->sCmn.SNR_dB_Q7;
177
178    /* Input quality is the average of the quality in the lowest two VAD bands */
179    psEncCtrl->input_quality_Q14 = ( opus_int )silk_RSHIFT( (opus_int32)psEnc->sCmn.input_quality_bands_Q15[ 0 ]
180        + psEnc->sCmn.input_quality_bands_Q15[ 1 ], 2 );
181
182    /* Coding quality level, between 0.0_Q0 and 1.0_Q0, but in Q14 */
183    psEncCtrl->coding_quality_Q14 = silk_RSHIFT( silk_sigm_Q15( silk_RSHIFT_ROUND( SNR_adj_dB_Q7 -
184        SILK_FIX_CONST( 20.0, 7 ), 4 ) ), 1 );
185
186    /* Reduce coding SNR during low speech activity */
187    if( psEnc->sCmn.useCBR == 0 ) {
188        b_Q8 = SILK_FIX_CONST( 1.0, 8 ) - psEnc->sCmn.speech_activity_Q8;
189        b_Q8 = silk_SMULWB( silk_LSHIFT( b_Q8, 8 ), b_Q8 );
190        SNR_adj_dB_Q7 = silk_SMLAWB( SNR_adj_dB_Q7,
191            silk_SMULBB( SILK_FIX_CONST( -BG_SNR_DECR_dB, 7 ) >> ( 4 + 1 ), b_Q8 ),                                       /* Q11*/
192            silk_SMULWB( SILK_FIX_CONST( 1.0, 14 ) + psEncCtrl->input_quality_Q14, psEncCtrl->coding_quality_Q14 ) );     /* Q12*/
193    }
194
195    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
196        /* Reduce gains for periodic signals */
197        SNR_adj_dB_Q7 = silk_SMLAWB( SNR_adj_dB_Q7, SILK_FIX_CONST( HARM_SNR_INCR_dB, 8 ), psEnc->LTPCorr_Q15 );
198    } else {
199        /* For unvoiced signals and low-quality input, adjust the quality slower than SNR_dB setting */
200        SNR_adj_dB_Q7 = silk_SMLAWB( SNR_adj_dB_Q7,
201            silk_SMLAWB( SILK_FIX_CONST( 6.0, 9 ), -SILK_FIX_CONST( 0.4, 18 ), psEnc->sCmn.SNR_dB_Q7 ),
202            SILK_FIX_CONST( 1.0, 14 ) - psEncCtrl->input_quality_Q14 );
203    }
204
205    /*************************/
206    /* SPARSENESS PROCESSING */
207    /*************************/
208    /* Set quantizer offset */
209    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
210        /* Initially set to 0; may be overruled in process_gains(..) */
211        psEnc->sCmn.indices.quantOffsetType = 0;
212        psEncCtrl->sparseness_Q8 = 0;
213    } else {
214        /* Sparseness measure, based on relative fluctuations of energy per 2 milliseconds */
215        nSamples = silk_LSHIFT( psEnc->sCmn.fs_kHz, 1 );
216        energy_variation_Q7 = 0;
217        log_energy_prev_Q7  = 0;
218        pitch_res_ptr = pitch_res;
219        for( k = 0; k < silk_SMULBB( SUB_FRAME_LENGTH_MS, psEnc->sCmn.nb_subfr ) / 2; k++ ) {
220            silk_sum_sqr_shift( &nrg, &scale, pitch_res_ptr, nSamples );
221            nrg += silk_RSHIFT( nSamples, scale );           /* Q(-scale)*/
222
223            log_energy_Q7 = silk_lin2log( nrg );
224            if( k > 0 ) {
225                energy_variation_Q7 += silk_abs( log_energy_Q7 - log_energy_prev_Q7 );
226            }
227            log_energy_prev_Q7 = log_energy_Q7;
228            pitch_res_ptr += nSamples;
229        }
230
231        psEncCtrl->sparseness_Q8 = silk_RSHIFT( silk_sigm_Q15( silk_SMULWB( energy_variation_Q7 -
232            SILK_FIX_CONST( 5.0, 7 ), SILK_FIX_CONST( 0.1, 16 ) ) ), 7 );
233
234        /* Set quantization offset depending on sparseness measure */
235        if( psEncCtrl->sparseness_Q8 > SILK_FIX_CONST( SPARSENESS_THRESHOLD_QNT_OFFSET, 8 ) ) {
236            psEnc->sCmn.indices.quantOffsetType = 0;
237        } else {
238            psEnc->sCmn.indices.quantOffsetType = 1;
239        }
240
241        /* Increase coding SNR for sparse signals */
242        SNR_adj_dB_Q7 = silk_SMLAWB( SNR_adj_dB_Q7, SILK_FIX_CONST( SPARSE_SNR_INCR_dB, 15 ), psEncCtrl->sparseness_Q8 - SILK_FIX_CONST( 0.5, 8 ) );
243    }
244
245    /*******************************/
246    /* Control bandwidth expansion */
247    /*******************************/
248    /* More BWE for signals with high prediction gain */
249    strength_Q16 = silk_SMULWB( psEncCtrl->predGain_Q16, SILK_FIX_CONST( FIND_PITCH_WHITE_NOISE_FRACTION, 16 ) );
250    BWExp1_Q16 = BWExp2_Q16 = silk_DIV32_varQ( SILK_FIX_CONST( BANDWIDTH_EXPANSION, 16 ),
251        silk_SMLAWW( SILK_FIX_CONST( 1.0, 16 ), strength_Q16, strength_Q16 ), 16 );
252    delta_Q16  = silk_SMULWB( SILK_FIX_CONST( 1.0, 16 ) - silk_SMULBB( 3, psEncCtrl->coding_quality_Q14 ),
253        SILK_FIX_CONST( LOW_RATE_BANDWIDTH_EXPANSION_DELTA, 16 ) );
254    BWExp1_Q16 = silk_SUB32( BWExp1_Q16, delta_Q16 );
255    BWExp2_Q16 = silk_ADD32( BWExp2_Q16, delta_Q16 );
256    /* BWExp1 will be applied after BWExp2, so make it relative */
257    BWExp1_Q16 = silk_DIV32_16( silk_LSHIFT( BWExp1_Q16, 14 ), silk_RSHIFT( BWExp2_Q16, 2 ) );
258
259    if( psEnc->sCmn.warping_Q16 > 0 ) {
260        /* Slightly more warping in analysis will move quantization noise up in frequency, where it's better masked */
261        warping_Q16 = silk_SMLAWB( psEnc->sCmn.warping_Q16, (opus_int32)psEncCtrl->coding_quality_Q14, SILK_FIX_CONST( 0.01, 18 ) );
262    } else {
263        warping_Q16 = 0;
264    }
265
266    /********************************************/
267    /* Compute noise shaping AR coefs and gains */
268    /********************************************/
269    ALLOC( x_windowed, psEnc->sCmn.shapeWinLength, opus_int16 );
270    for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
271        /* Apply window: sine slope followed by flat part followed by cosine slope */
272        opus_int shift, slope_part, flat_part;
273        flat_part = psEnc->sCmn.fs_kHz * 3;
274        slope_part = silk_RSHIFT( psEnc->sCmn.shapeWinLength - flat_part, 1 );
275
276        silk_apply_sine_window( x_windowed, x_ptr, 1, slope_part );
277        shift = slope_part;
278        silk_memcpy( x_windowed + shift, x_ptr + shift, flat_part * sizeof(opus_int16) );
279        shift += flat_part;
280        silk_apply_sine_window( x_windowed + shift, x_ptr + shift, 2, slope_part );
281
282        /* Update pointer: next LPC analysis block */
283        x_ptr += psEnc->sCmn.subfr_length;
284
285        if( psEnc->sCmn.warping_Q16 > 0 ) {
286            /* Calculate warped auto correlation */
287            silk_warped_autocorrelation_FIX( auto_corr, &scale, x_windowed, warping_Q16, psEnc->sCmn.shapeWinLength, psEnc->sCmn.shapingLPCOrder );
288        } else {
289            /* Calculate regular auto correlation */
290            silk_autocorr( auto_corr, &scale, x_windowed, psEnc->sCmn.shapeWinLength, psEnc->sCmn.shapingLPCOrder + 1, arch );
291        }
292
293        /* Add white noise, as a fraction of energy */
294        auto_corr[0] = silk_ADD32( auto_corr[0], silk_max_32( silk_SMULWB( silk_RSHIFT( auto_corr[ 0 ], 4 ),
295            SILK_FIX_CONST( SHAPE_WHITE_NOISE_FRACTION, 20 ) ), 1 ) );
296
297        /* Calculate the reflection coefficients using schur */
298        nrg = silk_schur64( refl_coef_Q16, auto_corr, psEnc->sCmn.shapingLPCOrder );
299        silk_assert( nrg >= 0 );
300
301        /* Convert reflection coefficients to prediction coefficients */
302        silk_k2a_Q16( AR2_Q24, refl_coef_Q16, psEnc->sCmn.shapingLPCOrder );
303
304        Qnrg = -scale;          /* range: -12...30*/
305        silk_assert( Qnrg >= -12 );
306        silk_assert( Qnrg <=  30 );
307
308        /* Make sure that Qnrg is an even number */
309        if( Qnrg & 1 ) {
310            Qnrg -= 1;
311            nrg >>= 1;
312        }
313
314        tmp32 = silk_SQRT_APPROX( nrg );
315        Qnrg >>= 1;             /* range: -6...15*/
316
317        psEncCtrl->Gains_Q16[ k ] = silk_LSHIFT_SAT32( tmp32, 16 - Qnrg );
318
319        if( psEnc->sCmn.warping_Q16 > 0 ) {
320            /* Adjust gain for warping */
321            gain_mult_Q16 = warped_gain( AR2_Q24, warping_Q16, psEnc->sCmn.shapingLPCOrder );
322            silk_assert( psEncCtrl->Gains_Q16[ k ] >= 0 );
323            if ( silk_SMULWW( silk_RSHIFT_ROUND( psEncCtrl->Gains_Q16[ k ], 1 ), gain_mult_Q16 ) >= ( silk_int32_MAX >> 1 ) ) {
324               psEncCtrl->Gains_Q16[ k ] = silk_int32_MAX;
325            } else {
326               psEncCtrl->Gains_Q16[ k ] = silk_SMULWW( psEncCtrl->Gains_Q16[ k ], gain_mult_Q16 );
327            }
328        }
329
330        /* Bandwidth expansion for synthesis filter shaping */
331        silk_bwexpander_32( AR2_Q24, psEnc->sCmn.shapingLPCOrder, BWExp2_Q16 );
332
333        /* Compute noise shaping filter coefficients */
334        silk_memcpy( AR1_Q24, AR2_Q24, psEnc->sCmn.shapingLPCOrder * sizeof( opus_int32 ) );
335
336        /* Bandwidth expansion for analysis filter shaping */
337        silk_assert( BWExp1_Q16 <= SILK_FIX_CONST( 1.0, 16 ) );
338        silk_bwexpander_32( AR1_Q24, psEnc->sCmn.shapingLPCOrder, BWExp1_Q16 );
339
340        /* Ratio of prediction gains, in energy domain */
341        pre_nrg_Q30 = silk_LPC_inverse_pred_gain_Q24( AR2_Q24, psEnc->sCmn.shapingLPCOrder );
342        nrg         = silk_LPC_inverse_pred_gain_Q24( AR1_Q24, psEnc->sCmn.shapingLPCOrder );
343
344        /*psEncCtrl->GainsPre[ k ] = 1.0f - 0.7f * ( 1.0f - pre_nrg / nrg ) = 0.3f + 0.7f * pre_nrg / nrg;*/
345        pre_nrg_Q30 = silk_LSHIFT32( silk_SMULWB( pre_nrg_Q30, SILK_FIX_CONST( 0.7, 15 ) ), 1 );
346        psEncCtrl->GainsPre_Q14[ k ] = ( opus_int ) SILK_FIX_CONST( 0.3, 14 ) + silk_DIV32_varQ( pre_nrg_Q30, nrg, 14 );
347
348        /* Convert to monic warped prediction coefficients and limit absolute values */
349        limit_warped_coefs( AR2_Q24, AR1_Q24, warping_Q16, SILK_FIX_CONST( 3.999, 24 ), psEnc->sCmn.shapingLPCOrder );
350
351        /* Convert from Q24 to Q13 and store in int16 */
352        for( i = 0; i < psEnc->sCmn.shapingLPCOrder; i++ ) {
353            psEncCtrl->AR1_Q13[ k * MAX_SHAPE_LPC_ORDER + i ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( AR1_Q24[ i ], 11 ) );
354            psEncCtrl->AR2_Q13[ k * MAX_SHAPE_LPC_ORDER + i ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( AR2_Q24[ i ], 11 ) );
355        }
356    }
357
358    /*****************/
359    /* Gain tweaking */
360    /*****************/
361    /* Increase gains during low speech activity and put lower limit on gains */
362    gain_mult_Q16 = silk_log2lin( -silk_SMLAWB( -SILK_FIX_CONST( 16.0, 7 ), SNR_adj_dB_Q7, SILK_FIX_CONST( 0.16, 16 ) ) );
363    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 ) ) );
364    silk_assert( gain_mult_Q16 > 0 );
365    for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
366        psEncCtrl->Gains_Q16[ k ] = silk_SMULWW( psEncCtrl->Gains_Q16[ k ], gain_mult_Q16 );
367        silk_assert( psEncCtrl->Gains_Q16[ k ] >= 0 );
368        psEncCtrl->Gains_Q16[ k ] = silk_ADD_POS_SAT32( psEncCtrl->Gains_Q16[ k ], gain_add_Q16 );
369    }
370
371    gain_mult_Q16 = SILK_FIX_CONST( 1.0, 16 ) + silk_RSHIFT_ROUND( silk_MLA( SILK_FIX_CONST( INPUT_TILT, 26 ),
372        psEncCtrl->coding_quality_Q14, SILK_FIX_CONST( HIGH_RATE_INPUT_TILT, 12 ) ), 10 );
373    for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
374        psEncCtrl->GainsPre_Q14[ k ] = silk_SMULWB( gain_mult_Q16, psEncCtrl->GainsPre_Q14[ k ] );
375    }
376
377    /************************************************/
378    /* Control low-frequency shaping and noise tilt */
379    /************************************************/
380    /* Less low frequency shaping for noisy inputs */
381    strength_Q16 = silk_MUL( SILK_FIX_CONST( LOW_FREQ_SHAPING, 4 ), silk_SMLAWB( SILK_FIX_CONST( 1.0, 12 ),
382        SILK_FIX_CONST( LOW_QUALITY_LOW_FREQ_SHAPING_DECR, 13 ), psEnc->sCmn.input_quality_bands_Q15[ 0 ] - SILK_FIX_CONST( 1.0, 15 ) ) );
383    strength_Q16 = silk_RSHIFT( silk_MUL( strength_Q16, psEnc->sCmn.speech_activity_Q8 ), 8 );
384    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
385        /* Reduce low frequencies quantization noise for periodic signals, depending on pitch lag */
386        /*f = 400; freqz([1, -0.98 + 2e-4 * f], [1, -0.97 + 7e-4 * f], 2^12, Fs); axis([0, 1000, -10, 1])*/
387        opus_int fs_kHz_inv = silk_DIV32_16( SILK_FIX_CONST( 0.2, 14 ), psEnc->sCmn.fs_kHz );
388        for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
389            b_Q14 = fs_kHz_inv + silk_DIV32_16( SILK_FIX_CONST( 3.0, 14 ), psEncCtrl->pitchL[ k ] );
390            /* Pack two coefficients in one int32 */
391            psEncCtrl->LF_shp_Q14[ k ]  = silk_LSHIFT( SILK_FIX_CONST( 1.0, 14 ) - b_Q14 - silk_SMULWB( strength_Q16, b_Q14 ), 16 );
392            psEncCtrl->LF_shp_Q14[ k ] |= (opus_uint16)( b_Q14 - SILK_FIX_CONST( 1.0, 14 ) );
393        }
394        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*/
395        Tilt_Q16 = - SILK_FIX_CONST( HP_NOISE_COEF, 16 ) -
396            silk_SMULWB( SILK_FIX_CONST( 1.0, 16 ) - SILK_FIX_CONST( HP_NOISE_COEF, 16 ),
397                silk_SMULWB( SILK_FIX_CONST( HARM_HP_NOISE_COEF, 24 ), psEnc->sCmn.speech_activity_Q8 ) );
398    } else {
399        b_Q14 = silk_DIV32_16( 21299, psEnc->sCmn.fs_kHz ); /* 1.3_Q0 = 21299_Q14*/
400        /* Pack two coefficients in one int32 */
401        psEncCtrl->LF_shp_Q14[ 0 ]  = silk_LSHIFT( SILK_FIX_CONST( 1.0, 14 ) - b_Q14 -
402            silk_SMULWB( strength_Q16, silk_SMULWB( SILK_FIX_CONST( 0.6, 16 ), b_Q14 ) ), 16 );
403        psEncCtrl->LF_shp_Q14[ 0 ] |= (opus_uint16)( b_Q14 - SILK_FIX_CONST( 1.0, 14 ) );
404        for( k = 1; k < psEnc->sCmn.nb_subfr; k++ ) {
405            psEncCtrl->LF_shp_Q14[ k ] = psEncCtrl->LF_shp_Q14[ 0 ];
406        }
407        Tilt_Q16 = -SILK_FIX_CONST( HP_NOISE_COEF, 16 );
408    }
409
410    /****************************/
411    /* HARMONIC SHAPING CONTROL */
412    /****************************/
413    /* Control boosting of harmonic frequencies */
414    HarmBoost_Q16 = silk_SMULWB( silk_SMULWB( SILK_FIX_CONST( 1.0, 17 ) - silk_LSHIFT( psEncCtrl->coding_quality_Q14, 3 ),
415        psEnc->LTPCorr_Q15 ), SILK_FIX_CONST( LOW_RATE_HARMONIC_BOOST, 16 ) );
416
417    /* More harmonic boost for noisy input signals */
418    HarmBoost_Q16 = silk_SMLAWB( HarmBoost_Q16,
419        SILK_FIX_CONST( 1.0, 16 ) - silk_LSHIFT( psEncCtrl->input_quality_Q14, 2 ), SILK_FIX_CONST( LOW_INPUT_QUALITY_HARMONIC_BOOST, 16 ) );
420
421    if( USE_HARM_SHAPING && psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
422        /* More harmonic noise shaping for high bitrates or noisy input */
423        HarmShapeGain_Q16 = silk_SMLAWB( SILK_FIX_CONST( HARMONIC_SHAPING, 16 ),
424                SILK_FIX_CONST( 1.0, 16 ) - silk_SMULWB( SILK_FIX_CONST( 1.0, 18 ) - silk_LSHIFT( psEncCtrl->coding_quality_Q14, 4 ),
425                psEncCtrl->input_quality_Q14 ), SILK_FIX_CONST( HIGH_RATE_OR_LOW_QUALITY_HARMONIC_SHAPING, 16 ) );
426
427        /* Less harmonic noise shaping for less periodic signals */
428        HarmShapeGain_Q16 = silk_SMULWB( silk_LSHIFT( HarmShapeGain_Q16, 1 ),
429            silk_SQRT_APPROX( silk_LSHIFT( psEnc->LTPCorr_Q15, 15 ) ) );
430    } else {
431        HarmShapeGain_Q16 = 0;
432    }
433
434    /*************************/
435    /* Smooth over subframes */
436    /*************************/
437    for( k = 0; k < MAX_NB_SUBFR; k++ ) {
438        psShapeSt->HarmBoost_smth_Q16 =
439            silk_SMLAWB( psShapeSt->HarmBoost_smth_Q16,     HarmBoost_Q16     - psShapeSt->HarmBoost_smth_Q16,     SILK_FIX_CONST( SUBFR_SMTH_COEF, 16 ) );
440        psShapeSt->HarmShapeGain_smth_Q16 =
441            silk_SMLAWB( psShapeSt->HarmShapeGain_smth_Q16, HarmShapeGain_Q16 - psShapeSt->HarmShapeGain_smth_Q16, SILK_FIX_CONST( SUBFR_SMTH_COEF, 16 ) );
442        psShapeSt->Tilt_smth_Q16 =
443            silk_SMLAWB( psShapeSt->Tilt_smth_Q16,          Tilt_Q16          - psShapeSt->Tilt_smth_Q16,          SILK_FIX_CONST( SUBFR_SMTH_COEF, 16 ) );
444
445        psEncCtrl->HarmBoost_Q14[ k ]     = ( opus_int )silk_RSHIFT_ROUND( psShapeSt->HarmBoost_smth_Q16,     2 );
446        psEncCtrl->HarmShapeGain_Q14[ k ] = ( opus_int )silk_RSHIFT_ROUND( psShapeSt->HarmShapeGain_smth_Q16, 2 );
447        psEncCtrl->Tilt_Q14[ k ]          = ( opus_int )silk_RSHIFT_ROUND( psShapeSt->Tilt_smth_Q16,          2 );
448    }
449    RESTORE_STACK;
450}
451#endif /* OVERRIDE_silk_noise_shape_analysis_FIX */
452