e24d2e9d338c95fe956866a128d025bde8798aba
[opus.git] / silk / fixed / noise_shape_analysis_FIX.c
1 /***********************************************************************
2 Copyright (c) 2006-2011, Skype Limited. All rights reserved.
3 Redistribution and use in source and binary forms, with or without
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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
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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
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23 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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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_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 /**************************************************************/
142 /* Compute noise shaping coefficients and initial gain values */
143 /**************************************************************/
144 void silk_noise_shape_analysis_FIX(
145     silk_encoder_state_FIX          *psEnc,                                 /* I/O  Encoder state FIX                                                           */
146     silk_encoder_control_FIX        *psEncCtrl,                             /* I/O  Encoder control FIX                                                         */
147     const opus_int16                *pitch_res,                             /* I    LPC residual from pitch analysis                                            */
148     const opus_int16                *x,                                     /* I    Input signal [ frame_length + la_shape ]                                    */
149     int                              arch                                   /* I    Run-time architecture                                                       */
150 )
151 {
152     silk_shape_state_FIX *psShapeSt = &psEnc->sShape;
153     opus_int     k, i, nSamples, Qnrg, b_Q14, warping_Q16, scale = 0;
154     opus_int32   SNR_adj_dB_Q7, HarmBoost_Q16, HarmShapeGain_Q16, Tilt_Q16, tmp32;
155     opus_int32   nrg, pre_nrg_Q30, log_energy_Q7, log_energy_prev_Q7, energy_variation_Q7;
156     opus_int32   delta_Q16, BWExp1_Q16, BWExp2_Q16, gain_mult_Q16, gain_add_Q16, strength_Q16, b_Q8;
157     opus_int32   auto_corr[     MAX_SHAPE_LPC_ORDER + 1 ];
158     opus_int32   refl_coef_Q16[ MAX_SHAPE_LPC_ORDER ];
159     opus_int32   AR1_Q24[       MAX_SHAPE_LPC_ORDER ];
160     opus_int32   AR2_Q24[       MAX_SHAPE_LPC_ORDER ];
161     VARDECL( opus_int16, x_windowed );
162     const opus_int16 *x_ptr, *pitch_res_ptr;
163     SAVE_STACK;
164
165     /* Point to start of first LPC analysis block */
166     x_ptr = x - psEnc->sCmn.la_shape;
167
168     /****************/
169     /* GAIN CONTROL */
170     /****************/
171     SNR_adj_dB_Q7 = psEnc->sCmn.SNR_dB_Q7;
172
173     /* Input quality is the average of the quality in the lowest two VAD bands */
174     psEncCtrl->input_quality_Q14 = ( opus_int )silk_RSHIFT( (opus_int32)psEnc->sCmn.input_quality_bands_Q15[ 0 ]
175         + psEnc->sCmn.input_quality_bands_Q15[ 1 ], 2 );
176
177     /* Coding quality level, between 0.0_Q0 and 1.0_Q0, but in Q14 */
178     psEncCtrl->coding_quality_Q14 = silk_RSHIFT( silk_sigm_Q15( silk_RSHIFT_ROUND( SNR_adj_dB_Q7 -
179         SILK_FIX_CONST( 20.0, 7 ), 4 ) ), 1 );
180
181     /* Reduce coding SNR during low speech activity */
182     if( psEnc->sCmn.useCBR == 0 ) {
183         b_Q8 = SILK_FIX_CONST( 1.0, 8 ) - psEnc->sCmn.speech_activity_Q8;
184         b_Q8 = silk_SMULWB( silk_LSHIFT( b_Q8, 8 ), b_Q8 );
185         SNR_adj_dB_Q7 = silk_SMLAWB( SNR_adj_dB_Q7,
186             silk_SMULBB( SILK_FIX_CONST( -BG_SNR_DECR_dB, 7 ) >> ( 4 + 1 ), b_Q8 ),                                       /* Q11*/
187             silk_SMULWB( SILK_FIX_CONST( 1.0, 14 ) + psEncCtrl->input_quality_Q14, psEncCtrl->coding_quality_Q14 ) );     /* Q12*/
188     }
189
190     if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
191         /* Reduce gains for periodic signals */
192         SNR_adj_dB_Q7 = silk_SMLAWB( SNR_adj_dB_Q7, SILK_FIX_CONST( HARM_SNR_INCR_dB, 8 ), psEnc->LTPCorr_Q15 );
193     } else {
194         /* For unvoiced signals and low-quality input, adjust the quality slower than SNR_dB setting */
195         SNR_adj_dB_Q7 = silk_SMLAWB( SNR_adj_dB_Q7,
196             silk_SMLAWB( SILK_FIX_CONST( 6.0, 9 ), -SILK_FIX_CONST( 0.4, 18 ), psEnc->sCmn.SNR_dB_Q7 ),
197             SILK_FIX_CONST( 1.0, 14 ) - psEncCtrl->input_quality_Q14 );
198     }
199
200     /*************************/
201     /* SPARSENESS PROCESSING */
202     /*************************/
203     /* Set quantizer offset */
204     if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
205         /* Initially set to 0; may be overruled in process_gains(..) */
206         psEnc->sCmn.indices.quantOffsetType = 0;
207         psEncCtrl->sparseness_Q8 = 0;
208     } else {
209         /* Sparseness measure, based on relative fluctuations of energy per 2 milliseconds */
210         nSamples = silk_LSHIFT( psEnc->sCmn.fs_kHz, 1 );
211         energy_variation_Q7 = 0;
212         log_energy_prev_Q7  = 0;
213         pitch_res_ptr = pitch_res;
214         for( k = 0; k < silk_SMULBB( SUB_FRAME_LENGTH_MS, psEnc->sCmn.nb_subfr ) / 2; k++ ) {
215             silk_sum_sqr_shift( &nrg, &scale, pitch_res_ptr, nSamples );
216             nrg += silk_RSHIFT( nSamples, scale );           /* Q(-scale)*/
217
218             log_energy_Q7 = silk_lin2log( nrg );
219             if( k > 0 ) {
220                 energy_variation_Q7 += silk_abs( log_energy_Q7 - log_energy_prev_Q7 );
221             }
222             log_energy_prev_Q7 = log_energy_Q7;
223             pitch_res_ptr += nSamples;
224         }
225
226         psEncCtrl->sparseness_Q8 = silk_RSHIFT( silk_sigm_Q15( silk_SMULWB( energy_variation_Q7 -
227             SILK_FIX_CONST( 5.0, 7 ), SILK_FIX_CONST( 0.1, 16 ) ) ), 7 );
228
229         /* Set quantization offset depending on sparseness measure */
230         if( psEncCtrl->sparseness_Q8 > SILK_FIX_CONST( SPARSENESS_THRESHOLD_QNT_OFFSET, 8 ) ) {
231             psEnc->sCmn.indices.quantOffsetType = 0;
232         } else {
233             psEnc->sCmn.indices.quantOffsetType = 1;
234         }
235
236         /* Increase coding SNR for sparse signals */
237         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 ) );
238     }
239
240     /*******************************/
241     /* Control bandwidth expansion */
242     /*******************************/
243     /* More BWE for signals with high prediction gain */
244     strength_Q16 = silk_SMULWB( psEncCtrl->predGain_Q16, SILK_FIX_CONST( FIND_PITCH_WHITE_NOISE_FRACTION, 16 ) );
245     BWExp1_Q16 = BWExp2_Q16 = silk_DIV32_varQ( SILK_FIX_CONST( BANDWIDTH_EXPANSION, 16 ),
246         silk_SMLAWW( SILK_FIX_CONST( 1.0, 16 ), strength_Q16, strength_Q16 ), 16 );
247     delta_Q16  = silk_SMULWB( SILK_FIX_CONST( 1.0, 16 ) - silk_SMULBB( 3, psEncCtrl->coding_quality_Q14 ),
248         SILK_FIX_CONST( LOW_RATE_BANDWIDTH_EXPANSION_DELTA, 16 ) );
249     BWExp1_Q16 = silk_SUB32( BWExp1_Q16, delta_Q16 );
250     BWExp2_Q16 = silk_ADD32( BWExp2_Q16, delta_Q16 );
251     /* BWExp1 will be applied after BWExp2, so make it relative */
252     BWExp1_Q16 = silk_DIV32_16( silk_LSHIFT( BWExp1_Q16, 14 ), silk_RSHIFT( BWExp2_Q16, 2 ) );
253
254     if( psEnc->sCmn.warping_Q16 > 0 ) {
255         /* Slightly more warping in analysis will move quantization noise up in frequency, where it's better masked */
256         warping_Q16 = silk_SMLAWB( psEnc->sCmn.warping_Q16, (opus_int32)psEncCtrl->coding_quality_Q14, SILK_FIX_CONST( 0.01, 18 ) );
257     } else {
258         warping_Q16 = 0;
259     }
260
261     /********************************************/
262     /* Compute noise shaping AR coefs and gains */
263     /********************************************/
264     ALLOC( x_windowed, psEnc->sCmn.shapeWinLength, opus_int16 );
265     for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
266         /* Apply window: sine slope followed by flat part followed by cosine slope */
267         opus_int shift, slope_part, flat_part;
268         flat_part = psEnc->sCmn.fs_kHz * 3;
269         slope_part = silk_RSHIFT( psEnc->sCmn.shapeWinLength - flat_part, 1 );
270
271         silk_apply_sine_window( x_windowed, x_ptr, 1, slope_part );
272         shift = slope_part;
273         silk_memcpy( x_windowed + shift, x_ptr + shift, flat_part * sizeof(opus_int16) );
274         shift += flat_part;
275         silk_apply_sine_window( x_windowed + shift, x_ptr + shift, 2, slope_part );
276
277         /* Update pointer: next LPC analysis block */
278         x_ptr += psEnc->sCmn.subfr_length;
279
280         if( psEnc->sCmn.warping_Q16 > 0 ) {
281             /* Calculate warped auto correlation */
282             silk_warped_autocorrelation_FIX( auto_corr, &scale, x_windowed, warping_Q16, psEnc->sCmn.shapeWinLength, psEnc->sCmn.shapingLPCOrder );
283         } else {
284             /* Calculate regular auto correlation */
285             silk_autocorr( auto_corr, &scale, x_windowed, psEnc->sCmn.shapeWinLength, psEnc->sCmn.shapingLPCOrder + 1, arch );
286         }
287
288         /* Add white noise, as a fraction of energy */
289         auto_corr[0] = silk_ADD32( auto_corr[0], silk_max_32( silk_SMULWB( silk_RSHIFT( auto_corr[ 0 ], 4 ),
290             SILK_FIX_CONST( SHAPE_WHITE_NOISE_FRACTION, 20 ) ), 1 ) );
291
292         /* Calculate the reflection coefficients using schur */
293         nrg = silk_schur64( refl_coef_Q16, auto_corr, psEnc->sCmn.shapingLPCOrder );
294         silk_assert( nrg >= 0 );
295
296         /* Convert reflection coefficients to prediction coefficients */
297         silk_k2a_Q16( AR2_Q24, refl_coef_Q16, psEnc->sCmn.shapingLPCOrder );
298
299         Qnrg = -scale;          /* range: -12...30*/
300         silk_assert( Qnrg >= -12 );
301         silk_assert( Qnrg <=  30 );
302
303         /* Make sure that Qnrg is an even number */
304         if( Qnrg & 1 ) {
305             Qnrg -= 1;
306             nrg >>= 1;
307         }
308
309         tmp32 = silk_SQRT_APPROX( nrg );
310         Qnrg >>= 1;             /* range: -6...15*/
311
312         psEncCtrl->Gains_Q16[ k ] = silk_LSHIFT_SAT32( tmp32, 16 - Qnrg );
313
314         if( psEnc->sCmn.warping_Q16 > 0 ) {
315             /* Adjust gain for warping */
316             gain_mult_Q16 = warped_gain( AR2_Q24, warping_Q16, psEnc->sCmn.shapingLPCOrder );
317             silk_assert( psEncCtrl->Gains_Q16[ k ] >= 0 );
318             if ( silk_SMULWW( silk_RSHIFT_ROUND( psEncCtrl->Gains_Q16[ k ], 1 ), gain_mult_Q16 ) >= ( silk_int32_MAX >> 1 ) ) {
319                psEncCtrl->Gains_Q16[ k ] = silk_int32_MAX;
320             } else {
321                psEncCtrl->Gains_Q16[ k ] = silk_SMULWW( psEncCtrl->Gains_Q16[ k ], gain_mult_Q16 );
322             }
323         }
324
325         /* Bandwidth expansion for synthesis filter shaping */
326         silk_bwexpander_32( AR2_Q24, psEnc->sCmn.shapingLPCOrder, BWExp2_Q16 );
327
328         /* Compute noise shaping filter coefficients */
329         silk_memcpy( AR1_Q24, AR2_Q24, psEnc->sCmn.shapingLPCOrder * sizeof( opus_int32 ) );
330
331         /* Bandwidth expansion for analysis filter shaping */
332         silk_assert( BWExp1_Q16 <= SILK_FIX_CONST( 1.0, 16 ) );
333         silk_bwexpander_32( AR1_Q24, psEnc->sCmn.shapingLPCOrder, BWExp1_Q16 );
334
335         /* Ratio of prediction gains, in energy domain */
336         pre_nrg_Q30 = silk_LPC_inverse_pred_gain_Q24( AR2_Q24, psEnc->sCmn.shapingLPCOrder );
337         nrg         = silk_LPC_inverse_pred_gain_Q24( AR1_Q24, psEnc->sCmn.shapingLPCOrder );
338
339         /*psEncCtrl->GainsPre[ k ] = 1.0f - 0.7f * ( 1.0f - pre_nrg / nrg ) = 0.3f + 0.7f * pre_nrg / nrg;*/
340         pre_nrg_Q30 = silk_LSHIFT32( silk_SMULWB( pre_nrg_Q30, SILK_FIX_CONST( 0.7, 15 ) ), 1 );
341         psEncCtrl->GainsPre_Q14[ k ] = ( opus_int ) SILK_FIX_CONST( 0.3, 14 ) + silk_DIV32_varQ( pre_nrg_Q30, nrg, 14 );
342
343         /* Convert to monic warped prediction coefficients and limit absolute values */
344         limit_warped_coefs( AR2_Q24, AR1_Q24, warping_Q16, SILK_FIX_CONST( 3.999, 24 ), psEnc->sCmn.shapingLPCOrder );
345
346         /* Convert from Q24 to Q13 and store in int16 */
347         for( i = 0; i < psEnc->sCmn.shapingLPCOrder; i++ ) {
348             psEncCtrl->AR1_Q13[ k * MAX_SHAPE_LPC_ORDER + i ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( AR1_Q24[ i ], 11 ) );
349             psEncCtrl->AR2_Q13[ k * MAX_SHAPE_LPC_ORDER + i ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( AR2_Q24[ i ], 11 ) );
350         }
351     }
352
353     /*****************/
354     /* Gain tweaking */
355     /*****************/
356     /* Increase gains during low speech activity and put lower limit on gains */
357     gain_mult_Q16 = silk_log2lin( -silk_SMLAWB( -SILK_FIX_CONST( 16.0, 7 ), SNR_adj_dB_Q7, SILK_FIX_CONST( 0.16, 16 ) ) );
358     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 ) ) );
359     silk_assert( gain_mult_Q16 > 0 );
360     for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
361         psEncCtrl->Gains_Q16[ k ] = silk_SMULWW( psEncCtrl->Gains_Q16[ k ], gain_mult_Q16 );
362         silk_assert( psEncCtrl->Gains_Q16[ k ] >= 0 );
363         psEncCtrl->Gains_Q16[ k ] = silk_ADD_POS_SAT32( psEncCtrl->Gains_Q16[ k ], gain_add_Q16 );
364     }
365
366     gain_mult_Q16 = SILK_FIX_CONST( 1.0, 16 ) + silk_RSHIFT_ROUND( silk_MLA( SILK_FIX_CONST( INPUT_TILT, 26 ),
367         psEncCtrl->coding_quality_Q14, SILK_FIX_CONST( HIGH_RATE_INPUT_TILT, 12 ) ), 10 );
368     for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
369         psEncCtrl->GainsPre_Q14[ k ] = silk_SMULWB( gain_mult_Q16, psEncCtrl->GainsPre_Q14[ k ] );
370     }
371
372     /************************************************/
373     /* Control low-frequency shaping and noise tilt */
374     /************************************************/
375     /* Less low frequency shaping for noisy inputs */
376     strength_Q16 = silk_MUL( SILK_FIX_CONST( LOW_FREQ_SHAPING, 4 ), silk_SMLAWB( SILK_FIX_CONST( 1.0, 12 ),
377         SILK_FIX_CONST( LOW_QUALITY_LOW_FREQ_SHAPING_DECR, 13 ), psEnc->sCmn.input_quality_bands_Q15[ 0 ] - SILK_FIX_CONST( 1.0, 15 ) ) );
378     strength_Q16 = silk_RSHIFT( silk_MUL( strength_Q16, psEnc->sCmn.speech_activity_Q8 ), 8 );
379     if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
380         /* Reduce low frequencies quantization noise for periodic signals, depending on pitch lag */
381         /*f = 400; freqz([1, -0.98 + 2e-4 * f], [1, -0.97 + 7e-4 * f], 2^12, Fs); axis([0, 1000, -10, 1])*/
382         opus_int fs_kHz_inv = silk_DIV32_16( SILK_FIX_CONST( 0.2, 14 ), psEnc->sCmn.fs_kHz );
383         for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {
384             b_Q14 = fs_kHz_inv + silk_DIV32_16( SILK_FIX_CONST( 3.0, 14 ), psEncCtrl->pitchL[ k ] );
385             /* Pack two coefficients in one int32 */
386             psEncCtrl->LF_shp_Q14[ k ]  = silk_LSHIFT( SILK_FIX_CONST( 1.0, 14 ) - b_Q14 - silk_SMULWB( strength_Q16, b_Q14 ), 16 );
387             psEncCtrl->LF_shp_Q14[ k ] |= (opus_uint16)( b_Q14 - SILK_FIX_CONST( 1.0, 14 ) );
388         }
389         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*/
390         Tilt_Q16 = - SILK_FIX_CONST( HP_NOISE_COEF, 16 ) -
391             silk_SMULWB( SILK_FIX_CONST( 1.0, 16 ) - SILK_FIX_CONST( HP_NOISE_COEF, 16 ),
392                 silk_SMULWB( SILK_FIX_CONST( HARM_HP_NOISE_COEF, 24 ), psEnc->sCmn.speech_activity_Q8 ) );
393     } else {
394         b_Q14 = silk_DIV32_16( 21299, psEnc->sCmn.fs_kHz ); /* 1.3_Q0 = 21299_Q14*/
395         /* Pack two coefficients in one int32 */
396         psEncCtrl->LF_shp_Q14[ 0 ]  = silk_LSHIFT( SILK_FIX_CONST( 1.0, 14 ) - b_Q14 -
397             silk_SMULWB( strength_Q16, silk_SMULWB( SILK_FIX_CONST( 0.6, 16 ), b_Q14 ) ), 16 );
398         psEncCtrl->LF_shp_Q14[ 0 ] |= (opus_uint16)( b_Q14 - SILK_FIX_CONST( 1.0, 14 ) );
399         for( k = 1; k < psEnc->sCmn.nb_subfr; k++ ) {
400             psEncCtrl->LF_shp_Q14[ k ] = psEncCtrl->LF_shp_Q14[ 0 ];
401         }
402         Tilt_Q16 = -SILK_FIX_CONST( HP_NOISE_COEF, 16 );
403     }
404
405     /****************************/
406     /* HARMONIC SHAPING CONTROL */
407     /****************************/
408     /* Control boosting of harmonic frequencies */
409     HarmBoost_Q16 = silk_SMULWB( silk_SMULWB( SILK_FIX_CONST( 1.0, 17 ) - silk_LSHIFT( psEncCtrl->coding_quality_Q14, 3 ),
410         psEnc->LTPCorr_Q15 ), SILK_FIX_CONST( LOW_RATE_HARMONIC_BOOST, 16 ) );
411
412     /* More harmonic boost for noisy input signals */
413     HarmBoost_Q16 = silk_SMLAWB( HarmBoost_Q16,
414         SILK_FIX_CONST( 1.0, 16 ) - silk_LSHIFT( psEncCtrl->input_quality_Q14, 2 ), SILK_FIX_CONST( LOW_INPUT_QUALITY_HARMONIC_BOOST, 16 ) );
415
416     if( USE_HARM_SHAPING && psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
417         /* More harmonic noise shaping for high bitrates or noisy input */
418         HarmShapeGain_Q16 = silk_SMLAWB( SILK_FIX_CONST( HARMONIC_SHAPING, 16 ),
419                 SILK_FIX_CONST( 1.0, 16 ) - silk_SMULWB( SILK_FIX_CONST( 1.0, 18 ) - silk_LSHIFT( psEncCtrl->coding_quality_Q14, 4 ),
420                 psEncCtrl->input_quality_Q14 ), SILK_FIX_CONST( HIGH_RATE_OR_LOW_QUALITY_HARMONIC_SHAPING, 16 ) );
421
422         /* Less harmonic noise shaping for less periodic signals */
423         HarmShapeGain_Q16 = silk_SMULWB( silk_LSHIFT( HarmShapeGain_Q16, 1 ),
424             silk_SQRT_APPROX( silk_LSHIFT( psEnc->LTPCorr_Q15, 15 ) ) );
425     } else {
426         HarmShapeGain_Q16 = 0;
427     }
428
429     /*************************/
430     /* Smooth over subframes */
431     /*************************/
432     for( k = 0; k < MAX_NB_SUBFR; k++ ) {
433         psShapeSt->HarmBoost_smth_Q16 =
434             silk_SMLAWB( psShapeSt->HarmBoost_smth_Q16,     HarmBoost_Q16     - psShapeSt->HarmBoost_smth_Q16,     SILK_FIX_CONST( SUBFR_SMTH_COEF, 16 ) );
435         psShapeSt->HarmShapeGain_smth_Q16 =
436             silk_SMLAWB( psShapeSt->HarmShapeGain_smth_Q16, HarmShapeGain_Q16 - psShapeSt->HarmShapeGain_smth_Q16, SILK_FIX_CONST( SUBFR_SMTH_COEF, 16 ) );
437         psShapeSt->Tilt_smth_Q16 =
438             silk_SMLAWB( psShapeSt->Tilt_smth_Q16,          Tilt_Q16          - psShapeSt->Tilt_smth_Q16,          SILK_FIX_CONST( SUBFR_SMTH_COEF, 16 ) );
439
440         psEncCtrl->HarmBoost_Q14[ k ]     = ( opus_int )silk_RSHIFT_ROUND( psShapeSt->HarmBoost_smth_Q16,     2 );
441         psEncCtrl->HarmShapeGain_Q14[ k ] = ( opus_int )silk_RSHIFT_ROUND( psShapeSt->HarmShapeGain_smth_Q16, 2 );
442         psEncCtrl->Tilt_Q14[ k ]          = ( opus_int )silk_RSHIFT_ROUND( psShapeSt->Tilt_smth_Q16,          2 );
443     }
444     RESTORE_STACK;
445 }