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,
7this list of conditions and the following disclaimer.
8- Redistributions in binary form must reproduce the above copyright
9notice, this list of conditions and the following disclaimer in the
10documentation and/or other materials provided with the distribution.
11- Neither the name of Internet Society, IETF or IETF Trust, nor the
12names of specific contributors, may be used to endorse or promote
13products derived from this software without specific prior written
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
17IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
19LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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/*****************************************************************************
33* Pitch analyser function
34******************************************************************************/
35#include "SigProc_FLP.h"
36#include "SigProc_FIX.h"
37#include "pitch_est_defines.h"
38
39#define SCRATCH_SIZE        22
40#define eps                 1.192092896e-07f
41
42/************************************************************/
43/* Internally used functions                                */
44/************************************************************/
45static void silk_P_Ana_calc_corr_st3(
46    silk_float cross_corr_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ], /* O 3 DIM correlation array */
47    const silk_float    frame[],            /* I vector to correlate                                            */
48    opus_int            start_lag,          /* I start lag                                                      */
49    opus_int            sf_length,          /* I sub frame length                                               */
50    opus_int            nb_subfr,           /* I number of subframes                                            */
51    opus_int            complexity          /* I Complexity setting                                             */
52);
53
54static void silk_P_Ana_calc_energy_st3(
55    silk_float energies_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ], /* O 3 DIM correlation array */
56    const silk_float    frame[],            /* I vector to correlate                                            */
57    opus_int            start_lag,          /* I start lag                                                      */
58    opus_int            sf_length,          /* I sub frame length                                               */
59    opus_int            nb_subfr,           /* I number of subframes                                            */
60    opus_int            complexity          /* I Complexity setting                                             */
61);
62
63/************************************************************/
64/* CORE PITCH ANALYSIS FUNCTION                             */
65/************************************************************/
66opus_int silk_pitch_analysis_core_FLP(      /* O    Voicing estimate: 0 voiced, 1 unvoiced                      */
67    const silk_float    *frame,             /* I    Signal of length PE_FRAME_LENGTH_MS*Fs_kHz                  */
68    opus_int            *pitch_out,         /* O    Pitch lag values [nb_subfr]                                 */
69    opus_int16          *lagIndex,          /* O    Lag Index                                                   */
70    opus_int8           *contourIndex,      /* O    Pitch contour Index                                         */
71    silk_float          *LTPCorr,           /* I/O  Normalized correlation; input: value from previous frame    */
72    opus_int            prevLag,            /* I    Last lag of previous frame; set to zero is unvoiced         */
73    const silk_float    search_thres1,      /* I    First stage threshold for lag candidates 0 - 1              */
74    const silk_float    search_thres2,      /* I    Final threshold for lag candidates 0 - 1                    */
75    const opus_int      Fs_kHz,             /* I    sample frequency (kHz)                                      */
76    const opus_int      complexity,         /* I    Complexity setting, 0-2, where 2 is highest                 */
77    const opus_int      nb_subfr            /* I    Number of 5 ms subframes                                    */
78)
79{
80    opus_int   i, k, d, j;
81    silk_float frame_8kHz[  PE_MAX_FRAME_LENGTH_MS * 8 ];
82    silk_float frame_4kHz[  PE_MAX_FRAME_LENGTH_MS * 4 ];
83    opus_int16 frame_8_FIX[ PE_MAX_FRAME_LENGTH_MS * 8 ];
84    opus_int16 frame_4_FIX[ PE_MAX_FRAME_LENGTH_MS * 4 ];
85    opus_int32 filt_state[ 6 ];
86    silk_float threshold, contour_bias;
87    silk_float C[ PE_MAX_NB_SUBFR][ (PE_MAX_LAG >> 1) + 5 ];
88    silk_float CC[ PE_NB_CBKS_STAGE2_EXT ];
89    const silk_float *target_ptr, *basis_ptr;
90    double    cross_corr, normalizer, energy, energy_tmp;
91    opus_int   d_srch[ PE_D_SRCH_LENGTH ];
92    opus_int16 d_comp[ (PE_MAX_LAG >> 1) + 5 ];
93    opus_int   length_d_srch, length_d_comp;
94    silk_float Cmax, CCmax, CCmax_b, CCmax_new_b, CCmax_new;
95    opus_int   CBimax, CBimax_new, lag, start_lag, end_lag, lag_new;
96    opus_int   cbk_size;
97    silk_float lag_log2, prevLag_log2, delta_lag_log2_sqr;
98    silk_float energies_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ];
99    silk_float cross_corr_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ];
100    opus_int   lag_counter;
101    opus_int   frame_length, frame_length_8kHz, frame_length_4kHz;
102    opus_int   sf_length, sf_length_8kHz, sf_length_4kHz;
103    opus_int   min_lag, min_lag_8kHz, min_lag_4kHz;
104    opus_int   max_lag, max_lag_8kHz, max_lag_4kHz;
105    opus_int   nb_cbk_search;
106    const opus_int8 *Lag_CB_ptr;
107
108    /* Check for valid sampling frequency */
109    silk_assert( Fs_kHz == 8 || Fs_kHz == 12 || Fs_kHz == 16 );
110
111    /* Check for valid complexity setting */
112    silk_assert( complexity >= SILK_PE_MIN_COMPLEX );
113    silk_assert( complexity <= SILK_PE_MAX_COMPLEX );
114
115    silk_assert( search_thres1 >= 0.0f && search_thres1 <= 1.0f );
116    silk_assert( search_thres2 >= 0.0f && search_thres2 <= 1.0f );
117
118    /* Set up frame lengths max / min lag for the sampling frequency */
119    frame_length      = ( PE_LTP_MEM_LENGTH_MS + nb_subfr * PE_SUBFR_LENGTH_MS ) * Fs_kHz;
120    frame_length_4kHz = ( PE_LTP_MEM_LENGTH_MS + nb_subfr * PE_SUBFR_LENGTH_MS ) * 4;
121    frame_length_8kHz = ( PE_LTP_MEM_LENGTH_MS + nb_subfr * PE_SUBFR_LENGTH_MS ) * 8;
122    sf_length         = PE_SUBFR_LENGTH_MS * Fs_kHz;
123    sf_length_4kHz    = PE_SUBFR_LENGTH_MS * 4;
124    sf_length_8kHz    = PE_SUBFR_LENGTH_MS * 8;
125    min_lag           = PE_MIN_LAG_MS * Fs_kHz;
126    min_lag_4kHz      = PE_MIN_LAG_MS * 4;
127    min_lag_8kHz      = PE_MIN_LAG_MS * 8;
128    max_lag           = PE_MAX_LAG_MS * Fs_kHz - 1;
129    max_lag_4kHz      = PE_MAX_LAG_MS * 4;
130    max_lag_8kHz      = PE_MAX_LAG_MS * 8 - 1;
131
132    silk_memset(C, 0, sizeof(silk_float) * nb_subfr * ((PE_MAX_LAG >> 1) + 5));
133
134    /* Resample from input sampled at Fs_kHz to 8 kHz */
135    if( Fs_kHz == 16 ) {
136        /* Resample to 16 -> 8 khz */
137        opus_int16 frame_16_FIX[ 16 * PE_MAX_FRAME_LENGTH_MS ];
138        silk_float2short_array( frame_16_FIX, frame, frame_length );
139        silk_memset( filt_state, 0, 2 * sizeof( opus_int32 ) );
140        silk_resampler_down2( filt_state, frame_8_FIX, frame_16_FIX, frame_length );
141        silk_short2float_array( frame_8kHz, frame_8_FIX, frame_length_8kHz );
142    } else if( Fs_kHz == 12 ) {
143        /* Resample to 12 -> 8 khz */
144        opus_int16 frame_12_FIX[ 12 * PE_MAX_FRAME_LENGTH_MS ];
145        silk_float2short_array( frame_12_FIX, frame, frame_length );
146        silk_memset( filt_state, 0, 6 * sizeof( opus_int32 ) );
147        silk_resampler_down2_3( filt_state, frame_8_FIX, frame_12_FIX, frame_length );
148        silk_short2float_array( frame_8kHz, frame_8_FIX, frame_length_8kHz );
149    } else {
150        silk_assert( Fs_kHz == 8 );
151        silk_float2short_array( frame_8_FIX, frame, frame_length_8kHz );
152    }
153
154    /* Decimate again to 4 kHz */
155    silk_memset( filt_state, 0, 2 * sizeof( opus_int32 ) );
156    silk_resampler_down2( filt_state, frame_4_FIX, frame_8_FIX, frame_length_8kHz );
157    silk_short2float_array( frame_4kHz, frame_4_FIX, frame_length_4kHz );
158
159    /* Low-pass filter */
160    for( i = frame_length_4kHz - 1; i > 0; i-- ) {
161        frame_4kHz[ i ] += frame_4kHz[ i - 1 ];
162    }
163
164    /******************************************************************************
165    * FIRST STAGE, operating in 4 khz
166    ******************************************************************************/
167    target_ptr = &frame_4kHz[ silk_LSHIFT( sf_length_4kHz, 2 ) ];
168    for( k = 0; k < nb_subfr >> 1; k++ ) {
169        /* Check that we are within range of the array */
170        silk_assert( target_ptr >= frame_4kHz );
171        silk_assert( target_ptr + sf_length_8kHz <= frame_4kHz + frame_length_4kHz );
172
173        basis_ptr = target_ptr - min_lag_4kHz;
174
175        /* Check that we are within range of the array */
176        silk_assert( basis_ptr >= frame_4kHz );
177        silk_assert( basis_ptr + sf_length_8kHz <= frame_4kHz + frame_length_4kHz );
178
179        /* Calculate first vector products before loop */
180        cross_corr = silk_inner_product_FLP( target_ptr, basis_ptr, sf_length_8kHz );
181        normalizer = silk_energy_FLP( basis_ptr, sf_length_8kHz ) + sf_length_8kHz * 4000.0f;
182
183        C[ 0 ][ min_lag_4kHz ] += (silk_float)(cross_corr / sqrt(normalizer));
184
185        /* From now on normalizer is computed recursively */
186        for(d = min_lag_4kHz + 1; d <= max_lag_4kHz; d++) {
187            basis_ptr--;
188
189            /* Check that we are within range of the array */
190            silk_assert( basis_ptr >= frame_4kHz );
191            silk_assert( basis_ptr + sf_length_8kHz <= frame_4kHz + frame_length_4kHz );
192
193            cross_corr = silk_inner_product_FLP(target_ptr, basis_ptr, sf_length_8kHz);
194
195            /* Add contribution of new sample and remove contribution from oldest sample */
196            normalizer +=
197                basis_ptr[ 0 ] * (double)basis_ptr[ 0 ] -
198                basis_ptr[ sf_length_8kHz ] * (double)basis_ptr[ sf_length_8kHz ];
199            C[ 0 ][ d ] += (silk_float)(cross_corr / sqrt( normalizer ));
200        }
201        /* Update target pointer */
202        target_ptr += sf_length_8kHz;
203    }
204
205    /* Apply short-lag bias */
206    for( i = max_lag_4kHz; i >= min_lag_4kHz; i-- ) {
207        C[ 0 ][ i ] -= C[ 0 ][ i ] * i / 4096.0f;
208    }
209
210    /* Sort */
211    length_d_srch = 4 + 2 * complexity;
212    silk_assert( 3 * length_d_srch <= PE_D_SRCH_LENGTH );
213    silk_insertion_sort_decreasing_FLP( &C[ 0 ][ min_lag_4kHz ], d_srch, max_lag_4kHz - min_lag_4kHz + 1, length_d_srch );
214
215    /* Escape if correlation is very low already here */
216    Cmax = C[ 0 ][ min_lag_4kHz ];
217    target_ptr = &frame_4kHz[ silk_SMULBB( sf_length_4kHz, nb_subfr ) ];
218    energy = 1000.0f;
219    for( i = 0; i < silk_LSHIFT( sf_length_4kHz, 2 ); i++ ) {
220        energy += target_ptr[i] * (double)target_ptr[i];
221    }
222    threshold = Cmax * Cmax;
223    if( energy / 16.0f > threshold ) {
224        silk_memset( pitch_out, 0, nb_subfr * sizeof( opus_int ) );
225        *LTPCorr      = 0.0f;
226        *lagIndex     = 0;
227        *contourIndex = 0;
228        return 1;
229    }
230
231    threshold = search_thres1 * Cmax;
232    for( i = 0; i < length_d_srch; i++ ) {
233        /* Convert to 8 kHz indices for the sorted correlation that exceeds the threshold */
234        if( C[ 0 ][ min_lag_4kHz + i ] > threshold ) {
235            d_srch[ i ] = silk_LSHIFT( d_srch[ i ] + min_lag_4kHz, 1 );
236        } else {
237            length_d_srch = i;
238            break;
239        }
240    }
241    silk_assert( length_d_srch > 0 );
242
243    for( i = min_lag_8kHz - 5; i < max_lag_8kHz + 5; i++ ) {
244        d_comp[ i ] = 0;
245    }
246    for( i = 0; i < length_d_srch; i++ ) {
247        d_comp[ d_srch[ i ] ] = 1;
248    }
249
250    /* Convolution */
251    for( i = max_lag_8kHz + 3; i >= min_lag_8kHz; i-- ) {
252        d_comp[ i ] += d_comp[ i - 1 ] + d_comp[ i - 2 ];
253    }
254
255    length_d_srch = 0;
256    for( i = min_lag_8kHz; i < max_lag_8kHz + 1; i++ ) {
257        if( d_comp[ i + 1 ] > 0 ) {
258            d_srch[ length_d_srch ] = i;
259            length_d_srch++;
260        }
261    }
262
263    /* Convolution */
264    for( i = max_lag_8kHz + 3; i >= min_lag_8kHz; i-- ) {
265        d_comp[ i ] += d_comp[ i - 1 ] + d_comp[ i - 2 ] + d_comp[ i - 3 ];
266    }
267
268    length_d_comp = 0;
269    for( i = min_lag_8kHz; i < max_lag_8kHz + 4; i++ ) {
270        if( d_comp[ i ] > 0 ) {
271            d_comp[ length_d_comp ] = (opus_int16)( i - 2 );
272            length_d_comp++;
273        }
274    }
275
276    /**********************************************************************************
277    ** SECOND STAGE, operating at 8 kHz, on lag sections with high correlation
278    *************************************************************************************/
279    /*********************************************************************************
280    * Find energy of each subframe projected onto its history, for a range of delays
281    *********************************************************************************/
282    silk_memset( C, 0, PE_MAX_NB_SUBFR*((PE_MAX_LAG >> 1) + 5) * sizeof(silk_float));
283
284    if( Fs_kHz == 8 ) {
285        target_ptr = &frame[ PE_LTP_MEM_LENGTH_MS * 8 ];
286    } else {
287        target_ptr = &frame_8kHz[ PE_LTP_MEM_LENGTH_MS * 8 ];
288    }
289    for( k = 0; k < nb_subfr; k++ ) {
290        energy_tmp = silk_energy_FLP( target_ptr, sf_length_8kHz );
291        for( j = 0; j < length_d_comp; j++ ) {
292            d = d_comp[ j ];
293            basis_ptr = target_ptr - d;
294            cross_corr = silk_inner_product_FLP( basis_ptr, target_ptr, sf_length_8kHz );
295            energy     = silk_energy_FLP( basis_ptr, sf_length_8kHz );
296            if( cross_corr > 0.0f ) {
297                C[ k ][ d ] = (silk_float)(cross_corr * cross_corr / (energy * energy_tmp + eps));
298            } else {
299                C[ k ][ d ] = 0.0f;
300            }
301        }
302        target_ptr += sf_length_8kHz;
303    }
304
305    /* search over lag range and lags codebook */
306    /* scale factor for lag codebook, as a function of center lag */
307
308    CCmax   = 0.0f; /* This value doesn't matter */
309    CCmax_b = -1000.0f;
310
311    CBimax = 0; /* To avoid returning undefined lag values */
312    lag = -1;   /* To check if lag with strong enough correlation has been found */
313
314    if( prevLag > 0 ) {
315        if( Fs_kHz == 12 ) {
316            prevLag = silk_LSHIFT( prevLag, 1 ) / 3;
317        } else if( Fs_kHz == 16 ) {
318            prevLag = silk_RSHIFT( prevLag, 1 );
319        }
320        prevLag_log2 = silk_log2((silk_float)prevLag);
321    } else {
322        prevLag_log2 = 0;
323    }
324
325    /* Set up stage 2 codebook based on number of subframes */
326    if( nb_subfr == PE_MAX_NB_SUBFR ) {
327        cbk_size   = PE_NB_CBKS_STAGE2_EXT;
328        Lag_CB_ptr = &silk_CB_lags_stage2[ 0 ][ 0 ];
329        if( Fs_kHz == 8 && complexity > SILK_PE_MIN_COMPLEX ) {
330            /* If input is 8 khz use a larger codebook here because it is last stage */
331            nb_cbk_search = PE_NB_CBKS_STAGE2_EXT;
332        } else {
333            nb_cbk_search = PE_NB_CBKS_STAGE2;
334        }
335    } else {
336        cbk_size       = PE_NB_CBKS_STAGE2_10MS;
337        Lag_CB_ptr     = &silk_CB_lags_stage2_10_ms[ 0 ][ 0 ];
338        nb_cbk_search  = PE_NB_CBKS_STAGE2_10MS;
339    }
340
341    for( k = 0; k < length_d_srch; k++ ) {
342        d = d_srch[ k ];
343        for( j = 0; j < nb_cbk_search; j++ ) {
344            CC[j] = 0.0f;
345            for( i = 0; i < nb_subfr; i++ ) {
346                /* Try all codebooks */
347                CC[ j ] += C[ i ][ d + matrix_ptr( Lag_CB_ptr, i, j, cbk_size )];
348            }
349        }
350        /* Find best codebook */
351        CCmax_new  = -1000.0f;
352        CBimax_new = 0;
353        for( i = 0; i < nb_cbk_search; i++ ) {
354            if( CC[ i ] > CCmax_new ) {
355                CCmax_new = CC[ i ];
356                CBimax_new = i;
357            }
358        }
359        CCmax_new = silk_max_float(CCmax_new, 0.0f); /* To avoid taking square root of negative number later */
360        CCmax_new_b = CCmax_new;
361
362        /* Bias towards shorter lags */
363        lag_log2 = silk_log2((silk_float)d);
364        CCmax_new_b -= PE_SHORTLAG_BIAS * nb_subfr * lag_log2;
365
366        /* Bias towards previous lag */
367        if( prevLag > 0 ) {
368            delta_lag_log2_sqr = lag_log2 - prevLag_log2;
369            delta_lag_log2_sqr *= delta_lag_log2_sqr;
370            CCmax_new_b -= PE_PREVLAG_BIAS * nb_subfr * (*LTPCorr) * delta_lag_log2_sqr / (delta_lag_log2_sqr + 0.5f);
371        }
372
373        if( CCmax_new_b > CCmax_b                                   &&  /* Find maximum biased correlation                  */
374            CCmax_new > nb_subfr * search_thres2 * search_thres2    &&  /* Correlation needs to be high enough to be voiced */
375            silk_CB_lags_stage2[ 0 ][ CBimax_new ] <= min_lag_8kHz      /* Lag must be in range                             */
376        ) {
377            CCmax_b = CCmax_new_b;
378            CCmax   = CCmax_new;
379            lag     = d;
380            CBimax  = CBimax_new;
381        }
382    }
383
384    if( lag == -1 ) {
385        /* No suitable candidate found */
386        silk_memset( pitch_out, 0, PE_MAX_NB_SUBFR * sizeof(opus_int) );
387        *LTPCorr      = 0.0f;
388        *lagIndex     = 0;
389        *contourIndex = 0;
390        return 1;
391    }
392
393    if( Fs_kHz > 8 ) {
394        /* Search in original signal */
395
396        /* Compensate for decimation */
397        silk_assert( lag == silk_SAT16( lag ) );
398        if( Fs_kHz == 12 ) {
399            lag = silk_RSHIFT_ROUND( silk_SMULBB( lag, 3 ), 1 );
400        } else { /* Fs_kHz == 16 */
401            lag = silk_LSHIFT( lag, 1 );
402        }
403
404        lag = silk_LIMIT_int( lag, min_lag, max_lag );
405        start_lag = silk_max_int( lag - 2, min_lag );
406        end_lag   = silk_min_int( lag + 2, max_lag );
407        lag_new   = lag;                                    /* to avoid undefined lag */
408        CBimax    = 0;                                      /* to avoid undefined lag */
409        silk_assert( CCmax >= 0.0f );
410        *LTPCorr = (silk_float)sqrt( CCmax / nb_subfr );    /* Output normalized correlation */
411
412        CCmax = -1000.0f;
413
414        /* Calculate the correlations and energies needed in stage 3 */
415        silk_P_Ana_calc_corr_st3( cross_corr_st3, frame, start_lag, sf_length, nb_subfr, complexity );
416        silk_P_Ana_calc_energy_st3( energies_st3, frame, start_lag, sf_length, nb_subfr, complexity );
417
418        lag_counter = 0;
419        silk_assert( lag == silk_SAT16( lag ) );
420        contour_bias = PE_FLATCONTOUR_BIAS / lag;
421
422        /* Set up cbk parameters according to complexity setting and frame length */
423        if( nb_subfr == PE_MAX_NB_SUBFR ) {
424            nb_cbk_search = (opus_int)silk_nb_cbk_searchs_stage3[ complexity ];
425            cbk_size      = PE_NB_CBKS_STAGE3_MAX;
426            Lag_CB_ptr    = &silk_CB_lags_stage3[ 0 ][ 0 ];
427        } else {
428            nb_cbk_search = PE_NB_CBKS_STAGE3_10MS;
429            cbk_size      = PE_NB_CBKS_STAGE3_10MS;
430            Lag_CB_ptr    = &silk_CB_lags_stage3_10_ms[ 0 ][ 0 ];
431        }
432
433        for( d = start_lag; d <= end_lag; d++ ) {
434            for( j = 0; j < nb_cbk_search; j++ ) {
435                cross_corr = 0.0;
436                energy = eps;
437                for( k = 0; k < nb_subfr; k++ ) {
438                    energy     +=   energies_st3[ k ][ j ][ lag_counter ];
439                    cross_corr += cross_corr_st3[ k ][ j ][ lag_counter ];
440                }
441                if( cross_corr > 0.0 ) {
442                    CCmax_new = (silk_float)(cross_corr * cross_corr / energy);
443                    /* Reduce depending on flatness of contour */
444                    CCmax_new *= 1.0f - contour_bias * j;
445                } else {
446                    CCmax_new = 0.0f;
447                }
448
449                if( CCmax_new > CCmax &&
450                   ( d + (opus_int)silk_CB_lags_stage3[ 0 ][ j ] ) <= max_lag
451                   ) {
452                    CCmax   = CCmax_new;
453                    lag_new = d;
454                    CBimax  = j;
455                }
456            }
457            lag_counter++;
458        }
459
460        for( k = 0; k < nb_subfr; k++ ) {
461            pitch_out[ k ] = lag_new + matrix_ptr( Lag_CB_ptr, k, CBimax, cbk_size );
462            pitch_out[ k ] = silk_LIMIT( pitch_out[ k ], min_lag, PE_MAX_LAG_MS * Fs_kHz );
463        }
464        *lagIndex = (opus_int16)( lag_new - min_lag );
465        *contourIndex = (opus_int8)CBimax;
466    } else {        /* Fs_kHz == 8 */
467        /* Save Lags and correlation */
468        silk_assert( CCmax >= 0.0f );
469        *LTPCorr = (silk_float)sqrt( CCmax / nb_subfr ); /* Output normalized correlation */
470        for( k = 0; k < nb_subfr; k++ ) {
471            pitch_out[ k ] = lag + matrix_ptr( Lag_CB_ptr, k, CBimax, cbk_size );
472            pitch_out[ k ] = silk_LIMIT( pitch_out[ k ], min_lag_8kHz, PE_MAX_LAG_MS * Fs_kHz );
473        }
474        *lagIndex = (opus_int16)( lag - min_lag_8kHz );
475        *contourIndex = (opus_int8)CBimax;
476    }
477    silk_assert( *lagIndex >= 0 );
478    /* return as voiced */
479    return 0;
480}
481
482static void silk_P_Ana_calc_corr_st3(
483    silk_float cross_corr_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ], /* O 3 DIM correlation array */
484    const silk_float    frame[],            /* I vector to correlate                                            */
485    opus_int            start_lag,          /* I start lag                                                      */
486    opus_int            sf_length,          /* I sub frame length                                               */
487    opus_int            nb_subfr,           /* I number of subframes                                            */
488    opus_int            complexity          /* I Complexity setting                                             */
489)
490    /***********************************************************************
491     Calculates the correlations used in stage 3 search. In order to cover
492     the whole lag codebook for all the searched offset lags (lag +- 2),
493     the following correlations are needed in each sub frame:
494
495     sf1: lag range [-8,...,7] total 16 correlations
496     sf2: lag range [-4,...,4] total 9 correlations
497     sf3: lag range [-3,....4] total 8 correltions
498     sf4: lag range [-6,....8] total 15 correlations
499
500     In total 48 correlations. The direct implementation computed in worst case
501     4*12*5 = 240 correlations, but more likely around 120.
502     **********************************************************************/
503{
504    const silk_float *target_ptr, *basis_ptr;
505    opus_int   i, j, k, lag_counter, lag_low, lag_high;
506    opus_int   nb_cbk_search, delta, idx, cbk_size;
507    silk_float scratch_mem[ SCRATCH_SIZE ];
508    const opus_int8 *Lag_range_ptr, *Lag_CB_ptr;
509
510    silk_assert( complexity >= SILK_PE_MIN_COMPLEX );
511    silk_assert( complexity <= SILK_PE_MAX_COMPLEX );
512
513    if( nb_subfr == PE_MAX_NB_SUBFR ) {
514        Lag_range_ptr = &silk_Lag_range_stage3[ complexity ][ 0 ][ 0 ];
515        Lag_CB_ptr    = &silk_CB_lags_stage3[ 0 ][ 0 ];
516        nb_cbk_search = silk_nb_cbk_searchs_stage3[ complexity ];
517        cbk_size      = PE_NB_CBKS_STAGE3_MAX;
518    } else {
519        silk_assert( nb_subfr == PE_MAX_NB_SUBFR >> 1);
520        Lag_range_ptr = &silk_Lag_range_stage3_10_ms[ 0 ][ 0 ];
521        Lag_CB_ptr    = &silk_CB_lags_stage3_10_ms[ 0 ][ 0 ];
522        nb_cbk_search = PE_NB_CBKS_STAGE3_10MS;
523        cbk_size      = PE_NB_CBKS_STAGE3_10MS;
524    }
525
526    target_ptr = &frame[ silk_LSHIFT( sf_length, 2 ) ]; /* Pointer to middle of frame */
527    for( k = 0; k < nb_subfr; k++ ) {
528        lag_counter = 0;
529
530        /* Calculate the correlations for each subframe */
531        lag_low  = matrix_ptr( Lag_range_ptr, k, 0, 2 );
532        lag_high = matrix_ptr( Lag_range_ptr, k, 1, 2 );
533        for( j = lag_low; j <= lag_high; j++ ) {
534            basis_ptr = target_ptr - ( start_lag + j );
535            silk_assert( lag_counter < SCRATCH_SIZE );
536            scratch_mem[ lag_counter ] = (silk_float)silk_inner_product_FLP( target_ptr, basis_ptr, sf_length );
537            lag_counter++;
538        }
539
540        delta = matrix_ptr( Lag_range_ptr, k, 0, 2 );
541        for( i = 0; i < nb_cbk_search; i++ ) {
542            /* Fill out the 3 dim array that stores the correlations for */
543            /* each code_book vector for each start lag */
544            idx = matrix_ptr( Lag_CB_ptr, k, i, cbk_size ) - delta;
545            for( j = 0; j < PE_NB_STAGE3_LAGS; j++ ) {
546                silk_assert( idx + j < SCRATCH_SIZE );
547                silk_assert( idx + j < lag_counter );
548                cross_corr_st3[ k ][ i ][ j ] = scratch_mem[ idx + j ];
549            }
550        }
551        target_ptr += sf_length;
552    }
553}
554
555static void silk_P_Ana_calc_energy_st3(
556    silk_float energies_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ], /* O 3 DIM correlation array */
557    const silk_float    frame[],            /* I vector to correlate                                            */
558    opus_int            start_lag,          /* I start lag                                                      */
559    opus_int            sf_length,          /* I sub frame length                                               */
560    opus_int            nb_subfr,           /* I number of subframes                                            */
561    opus_int            complexity          /* I Complexity setting                                             */
562)
563/****************************************************************
564Calculate the energies for first two subframes. The energies are
565calculated recursively.
566****************************************************************/
567{
568    const silk_float *target_ptr, *basis_ptr;
569    double    energy;
570    opus_int   k, i, j, lag_counter;
571    opus_int   nb_cbk_search, delta, idx, cbk_size, lag_diff;
572    silk_float scratch_mem[ SCRATCH_SIZE ];
573    const opus_int8 *Lag_range_ptr, *Lag_CB_ptr;
574
575    silk_assert( complexity >= SILK_PE_MIN_COMPLEX );
576    silk_assert( complexity <= SILK_PE_MAX_COMPLEX );
577
578    if( nb_subfr == PE_MAX_NB_SUBFR ) {
579        Lag_range_ptr = &silk_Lag_range_stage3[ complexity ][ 0 ][ 0 ];
580        Lag_CB_ptr    = &silk_CB_lags_stage3[ 0 ][ 0 ];
581        nb_cbk_search = silk_nb_cbk_searchs_stage3[ complexity ];
582        cbk_size      = PE_NB_CBKS_STAGE3_MAX;
583    } else {
584        silk_assert( nb_subfr == PE_MAX_NB_SUBFR >> 1);
585        Lag_range_ptr = &silk_Lag_range_stage3_10_ms[ 0 ][ 0 ];
586        Lag_CB_ptr    = &silk_CB_lags_stage3_10_ms[ 0 ][ 0 ];
587        nb_cbk_search = PE_NB_CBKS_STAGE3_10MS;
588        cbk_size      = PE_NB_CBKS_STAGE3_10MS;
589    }
590
591    target_ptr = &frame[ silk_LSHIFT( sf_length, 2 ) ];
592    for( k = 0; k < nb_subfr; k++ ) {
593        lag_counter = 0;
594
595        /* Calculate the energy for first lag */
596        basis_ptr = target_ptr - ( start_lag + matrix_ptr( Lag_range_ptr, k, 0, 2 ) );
597        energy = silk_energy_FLP( basis_ptr, sf_length ) + 1e-3;
598        silk_assert( energy >= 0.0 );
599        scratch_mem[lag_counter] = (silk_float)energy;
600        lag_counter++;
601
602        lag_diff = ( matrix_ptr( Lag_range_ptr, k, 1, 2 ) -  matrix_ptr( Lag_range_ptr, k, 0, 2 ) + 1 );
603        for( i = 1; i < lag_diff; i++ ) {
604            /* remove part outside new window */
605            energy -= basis_ptr[sf_length - i] * (double)basis_ptr[sf_length - i];
606            silk_assert( energy >= 0.0 );
607
608            /* add part that comes into window */
609            energy += basis_ptr[ -i ] * (double)basis_ptr[ -i ];
610            silk_assert( energy >= 0.0 );
611            silk_assert( lag_counter < SCRATCH_SIZE );
612            scratch_mem[lag_counter] = (silk_float)energy;
613            lag_counter++;
614        }
615
616        delta = matrix_ptr( Lag_range_ptr, k, 0, 2 );
617        for( i = 0; i < nb_cbk_search; i++ ) {
618            /* Fill out the 3 dim array that stores the correlations for    */
619            /* each code_book vector for each start lag                     */
620            idx = matrix_ptr( Lag_CB_ptr, k, i, cbk_size ) - delta;
621            for( j = 0; j < PE_NB_STAGE3_LAGS; j++ ) {
622                silk_assert( idx + j < SCRATCH_SIZE );
623                silk_assert( idx + j < lag_counter );
624                energies_st3[ k ][ i ][ j ] = scratch_mem[ idx + j ];
625                silk_assert( energies_st3[ k ][ i ][ j ] >= 0.0f );
626            }
627        }
628        target_ptr += sf_length;
629    }
630}
631