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#include "main_FIX.h"
33#include "stack_alloc.h"
34#include "tuning_parameters.h"
35
36/* Find pitch lags */
37void silk_find_pitch_lags_FIX(
38    silk_encoder_state_FIX          *psEnc,                                 /* I/O  encoder state                                                               */
39    silk_encoder_control_FIX        *psEncCtrl,                             /* I/O  encoder control                                                             */
40    opus_int16                      res[],                                  /* O    residual                                                                    */
41    const opus_int16                x[],                                    /* I    Speech signal                                                               */
42    int                             arch                                    /* I    Run-time architecture                                                       */
43)
44{
45    opus_int   buf_len, i, scale;
46    opus_int32 thrhld_Q13, res_nrg;
47    const opus_int16 *x_buf, *x_buf_ptr;
48    VARDECL( opus_int16, Wsig );
49    opus_int16 *Wsig_ptr;
50    opus_int32 auto_corr[ MAX_FIND_PITCH_LPC_ORDER + 1 ];
51    opus_int16 rc_Q15[    MAX_FIND_PITCH_LPC_ORDER ];
52    opus_int32 A_Q24[     MAX_FIND_PITCH_LPC_ORDER ];
53    opus_int16 A_Q12[     MAX_FIND_PITCH_LPC_ORDER ];
54    SAVE_STACK;
55
56    /******************************************/
57    /* Set up buffer lengths etc based on Fs  */
58    /******************************************/
59    buf_len = psEnc->sCmn.la_pitch + psEnc->sCmn.frame_length + psEnc->sCmn.ltp_mem_length;
60
61    /* Safety check */
62    silk_assert( buf_len >= psEnc->sCmn.pitch_LPC_win_length );
63
64    x_buf = x - psEnc->sCmn.ltp_mem_length;
65
66    /*************************************/
67    /* Estimate LPC AR coefficients      */
68    /*************************************/
69
70    /* Calculate windowed signal */
71
72    ALLOC( Wsig, psEnc->sCmn.pitch_LPC_win_length, opus_int16 );
73
74    /* First LA_LTP samples */
75    x_buf_ptr = x_buf + buf_len - psEnc->sCmn.pitch_LPC_win_length;
76    Wsig_ptr  = Wsig;
77    silk_apply_sine_window( Wsig_ptr, x_buf_ptr, 1, psEnc->sCmn.la_pitch );
78
79    /* Middle un - windowed samples */
80    Wsig_ptr  += psEnc->sCmn.la_pitch;
81    x_buf_ptr += psEnc->sCmn.la_pitch;
82    silk_memcpy( Wsig_ptr, x_buf_ptr, ( psEnc->sCmn.pitch_LPC_win_length - silk_LSHIFT( psEnc->sCmn.la_pitch, 1 ) ) * sizeof( opus_int16 ) );
83
84    /* Last LA_LTP samples */
85    Wsig_ptr  += psEnc->sCmn.pitch_LPC_win_length - silk_LSHIFT( psEnc->sCmn.la_pitch, 1 );
86    x_buf_ptr += psEnc->sCmn.pitch_LPC_win_length - silk_LSHIFT( psEnc->sCmn.la_pitch, 1 );
87    silk_apply_sine_window( Wsig_ptr, x_buf_ptr, 2, psEnc->sCmn.la_pitch );
88
89    /* Calculate autocorrelation sequence */
90    silk_autocorr( auto_corr, &scale, Wsig, psEnc->sCmn.pitch_LPC_win_length, psEnc->sCmn.pitchEstimationLPCOrder + 1, arch );
91
92    /* Add white noise, as fraction of energy */
93    auto_corr[ 0 ] = silk_SMLAWB( auto_corr[ 0 ], auto_corr[ 0 ], SILK_FIX_CONST( FIND_PITCH_WHITE_NOISE_FRACTION, 16 ) ) + 1;
94
95    /* Calculate the reflection coefficients using schur */
96    res_nrg = silk_schur( rc_Q15, auto_corr, psEnc->sCmn.pitchEstimationLPCOrder );
97
98    /* Prediction gain */
99    psEncCtrl->predGain_Q16 = silk_DIV32_varQ( auto_corr[ 0 ], silk_max_int( res_nrg, 1 ), 16 );
100
101    /* Convert reflection coefficients to prediction coefficients */
102    silk_k2a( A_Q24, rc_Q15, psEnc->sCmn.pitchEstimationLPCOrder );
103
104    /* Convert From 32 bit Q24 to 16 bit Q12 coefs */
105    for( i = 0; i < psEnc->sCmn.pitchEstimationLPCOrder; i++ ) {
106        A_Q12[ i ] = (opus_int16)silk_SAT16( silk_RSHIFT( A_Q24[ i ], 12 ) );
107    }
108
109    /* Do BWE */
110    silk_bwexpander( A_Q12, psEnc->sCmn.pitchEstimationLPCOrder, SILK_FIX_CONST( FIND_PITCH_BANDWIDTH_EXPANSION, 16 ) );
111
112    /*****************************************/
113    /* LPC analysis filtering                */
114    /*****************************************/
115    silk_LPC_analysis_filter( res, x_buf, A_Q12, buf_len, psEnc->sCmn.pitchEstimationLPCOrder );
116
117    if( psEnc->sCmn.indices.signalType != TYPE_NO_VOICE_ACTIVITY && psEnc->sCmn.first_frame_after_reset == 0 ) {
118        /* Threshold for pitch estimator */
119        thrhld_Q13 = SILK_FIX_CONST( 0.6, 13 );
120        thrhld_Q13 = silk_SMLABB( thrhld_Q13, SILK_FIX_CONST( -0.004, 13 ), psEnc->sCmn.pitchEstimationLPCOrder );
121        thrhld_Q13 = silk_SMLAWB( thrhld_Q13, SILK_FIX_CONST( -0.1,   21  ), psEnc->sCmn.speech_activity_Q8 );
122        thrhld_Q13 = silk_SMLABB( thrhld_Q13, SILK_FIX_CONST( -0.15,  13 ), silk_RSHIFT( psEnc->sCmn.prevSignalType, 1 ) );
123        thrhld_Q13 = silk_SMLAWB( thrhld_Q13, SILK_FIX_CONST( -0.1,   14 ), psEnc->sCmn.input_tilt_Q15 );
124        thrhld_Q13 = silk_SAT16(  thrhld_Q13 );
125
126        /*****************************************/
127        /* Call pitch estimator                  */
128        /*****************************************/
129        if( silk_pitch_analysis_core( res, psEncCtrl->pitchL, &psEnc->sCmn.indices.lagIndex, &psEnc->sCmn.indices.contourIndex,
130                &psEnc->LTPCorr_Q15, psEnc->sCmn.prevLag, psEnc->sCmn.pitchEstimationThreshold_Q16,
131                (opus_int)thrhld_Q13, psEnc->sCmn.fs_kHz, psEnc->sCmn.pitchEstimationComplexity, psEnc->sCmn.nb_subfr,
132                psEnc->sCmn.arch) == 0 )
133        {
134            psEnc->sCmn.indices.signalType = TYPE_VOICED;
135        } else {
136            psEnc->sCmn.indices.signalType = TYPE_UNVOICED;
137        }
138    } else {
139        silk_memset( psEncCtrl->pitchL, 0, sizeof( psEncCtrl->pitchL ) );
140        psEnc->sCmn.indices.lagIndex = 0;
141        psEnc->sCmn.indices.contourIndex = 0;
142        psEnc->LTPCorr_Q15 = 0;
143    }
144    RESTORE_STACK;
145}
146