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