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
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22INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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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.h"
33
34/* Decode parameters from payload */
35void silk_decode_parameters(
36    silk_decoder_state          *psDec,                         /* I/O  State                                       */
37    silk_decoder_control        *psDecCtrl,                     /* I/O  Decoder control                             */
38    opus_int                    condCoding                      /* I    The type of conditional coding to use       */
39)
40{
41    opus_int   i, k, Ix;
42    opus_int16 pNLSF_Q15[ MAX_LPC_ORDER ], pNLSF0_Q15[ MAX_LPC_ORDER ];
43    const opus_int8 *cbk_ptr_Q7;
44
45    /* Dequant Gains */
46    silk_gains_dequant( psDecCtrl->Gains_Q16, psDec->indices.GainsIndices,
47        &psDec->LastGainIndex, condCoding == CODE_CONDITIONALLY, psDec->nb_subfr );
48
49    /****************/
50    /* Decode NLSFs */
51    /****************/
52    silk_NLSF_decode( pNLSF_Q15, psDec->indices.NLSFIndices, psDec->psNLSF_CB );
53
54    /* Convert NLSF parameters to AR prediction filter coefficients */
55    silk_NLSF2A( psDecCtrl->PredCoef_Q12[ 1 ], pNLSF_Q15, psDec->LPC_order );
56
57    /* If just reset, e.g., because internal Fs changed, do not allow interpolation */
58    /* improves the case of packet loss in the first frame after a switch           */
59    if( psDec->first_frame_after_reset == 1 ) {
60        psDec->indices.NLSFInterpCoef_Q2 = 4;
61    }
62
63    if( psDec->indices.NLSFInterpCoef_Q2 < 4 ) {
64        /* Calculation of the interpolated NLSF0 vector from the interpolation factor, */
65        /* the previous NLSF1, and the current NLSF1                                   */
66        for( i = 0; i < psDec->LPC_order; i++ ) {
67            pNLSF0_Q15[ i ] = psDec->prevNLSF_Q15[ i ] + silk_RSHIFT( silk_MUL( psDec->indices.NLSFInterpCoef_Q2,
68                pNLSF_Q15[ i ] - psDec->prevNLSF_Q15[ i ] ), 2 );
69        }
70
71        /* Convert NLSF parameters to AR prediction filter coefficients */
72        silk_NLSF2A( psDecCtrl->PredCoef_Q12[ 0 ], pNLSF0_Q15, psDec->LPC_order );
73    } else {
74        /* Copy LPC coefficients for first half from second half */
75        silk_memcpy( psDecCtrl->PredCoef_Q12[ 0 ], psDecCtrl->PredCoef_Q12[ 1 ], psDec->LPC_order * sizeof( opus_int16 ) );
76    }
77
78    silk_memcpy( psDec->prevNLSF_Q15, pNLSF_Q15, psDec->LPC_order * sizeof( opus_int16 ) );
79
80    /* After a packet loss do BWE of LPC coefs */
81    if( psDec->lossCnt ) {
82        silk_bwexpander( psDecCtrl->PredCoef_Q12[ 0 ], psDec->LPC_order, BWE_AFTER_LOSS_Q16 );
83        silk_bwexpander( psDecCtrl->PredCoef_Q12[ 1 ], psDec->LPC_order, BWE_AFTER_LOSS_Q16 );
84    }
85
86    if( psDec->indices.signalType == TYPE_VOICED ) {
87        /*********************/
88        /* Decode pitch lags */
89        /*********************/
90
91        /* Decode pitch values */
92        silk_decode_pitch( psDec->indices.lagIndex, psDec->indices.contourIndex, psDecCtrl->pitchL, psDec->fs_kHz, psDec->nb_subfr );
93
94        /* Decode Codebook Index */
95        cbk_ptr_Q7 = silk_LTP_vq_ptrs_Q7[ psDec->indices.PERIndex ]; /* set pointer to start of codebook */
96
97        for( k = 0; k < psDec->nb_subfr; k++ ) {
98            Ix = psDec->indices.LTPIndex[ k ];
99            for( i = 0; i < LTP_ORDER; i++ ) {
100                psDecCtrl->LTPCoef_Q14[ k * LTP_ORDER + i ] = silk_LSHIFT( cbk_ptr_Q7[ Ix * LTP_ORDER + i ], 7 );
101            }
102        }
103
104        /**********************/
105        /* Decode LTP scaling */
106        /**********************/
107        Ix = psDec->indices.LTP_scaleIndex;
108        psDecCtrl->LTP_scale_Q14 = silk_LTPScales_table_Q14[ Ix ];
109    } else {
110        silk_memset( psDecCtrl->pitchL,      0,             psDec->nb_subfr * sizeof( opus_int   ) );
111        silk_memset( psDecCtrl->LTPCoef_Q14, 0, LTP_ORDER * psDec->nb_subfr * sizeof( opus_int16 ) );
112        psDec->indices.PERIndex  = 0;
113        psDecCtrl->LTP_scale_Q14 = 0;
114    }
115}
116