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.h"
33
34/* Decode side-information parameters from payload */
35void silk_decode_indices(
36    silk_decoder_state          *psDec,                         /* I/O  State                                       */
37    ec_dec                      *psRangeDec,                    /* I/O  Compressor data structure                   */
38    opus_int                    FrameIndex,                     /* I    Frame number                                */
39    opus_int                    decode_LBRR,                    /* I    Flag indicating LBRR data is being decoded  */
40    opus_int                    condCoding                      /* I    The type of conditional coding to use       */
41)
42{
43    opus_int   i, k, Ix;
44    opus_int   decode_absolute_lagIndex, delta_lagIndex;
45    opus_int16 ec_ix[ MAX_LPC_ORDER ];
46    opus_uint8 pred_Q8[ MAX_LPC_ORDER ];
47
48    /*******************************************/
49    /* Decode signal type and quantizer offset */
50    /*******************************************/
51    if( decode_LBRR || psDec->VAD_flags[ FrameIndex ] ) {
52        Ix = ec_dec_icdf( psRangeDec, silk_type_offset_VAD_iCDF, 8 ) + 2;
53    } else {
54        Ix = ec_dec_icdf( psRangeDec, silk_type_offset_no_VAD_iCDF, 8 );
55    }
56    psDec->indices.signalType      = (opus_int8)silk_RSHIFT( Ix, 1 );
57    psDec->indices.quantOffsetType = (opus_int8)( Ix & 1 );
58
59    /****************/
60    /* Decode gains */
61    /****************/
62    /* First subframe */
63    if( condCoding == CODE_CONDITIONALLY ) {
64        /* Conditional coding */
65        psDec->indices.GainsIndices[ 0 ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_delta_gain_iCDF, 8 );
66    } else {
67        /* Independent coding, in two stages: MSB bits followed by 3 LSBs */
68        psDec->indices.GainsIndices[ 0 ]  = (opus_int8)silk_LSHIFT( ec_dec_icdf( psRangeDec, silk_gain_iCDF[ psDec->indices.signalType ], 8 ), 3 );
69        psDec->indices.GainsIndices[ 0 ] += (opus_int8)ec_dec_icdf( psRangeDec, silk_uniform8_iCDF, 8 );
70    }
71
72    /* Remaining subframes */
73    for( i = 1; i < psDec->nb_subfr; i++ ) {
74        psDec->indices.GainsIndices[ i ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_delta_gain_iCDF, 8 );
75    }
76
77    /**********************/
78    /* Decode LSF Indices */
79    /**********************/
80    psDec->indices.NLSFIndices[ 0 ] = (opus_int8)ec_dec_icdf( psRangeDec, &psDec->psNLSF_CB->CB1_iCDF[ ( psDec->indices.signalType >> 1 ) * psDec->psNLSF_CB->nVectors ], 8 );
81    silk_NLSF_unpack( ec_ix, pred_Q8, psDec->psNLSF_CB, psDec->indices.NLSFIndices[ 0 ] );
82    silk_assert( psDec->psNLSF_CB->order == psDec->LPC_order );
83    for( i = 0; i < psDec->psNLSF_CB->order; i++ ) {
84        Ix = ec_dec_icdf( psRangeDec, &psDec->psNLSF_CB->ec_iCDF[ ec_ix[ i ] ], 8 );
85        if( Ix == 0 ) {
86            Ix -= ec_dec_icdf( psRangeDec, silk_NLSF_EXT_iCDF, 8 );
87        } else if( Ix == 2 * NLSF_QUANT_MAX_AMPLITUDE ) {
88            Ix += ec_dec_icdf( psRangeDec, silk_NLSF_EXT_iCDF, 8 );
89        }
90        psDec->indices.NLSFIndices[ i+1 ] = (opus_int8)( Ix - NLSF_QUANT_MAX_AMPLITUDE );
91    }
92
93    /* Decode LSF interpolation factor */
94    if( psDec->nb_subfr == MAX_NB_SUBFR ) {
95        psDec->indices.NLSFInterpCoef_Q2 = (opus_int8)ec_dec_icdf( psRangeDec, silk_NLSF_interpolation_factor_iCDF, 8 );
96    } else {
97        psDec->indices.NLSFInterpCoef_Q2 = 4;
98    }
99
100    if( psDec->indices.signalType == TYPE_VOICED )
101    {
102        /*********************/
103        /* Decode pitch lags */
104        /*********************/
105        /* Get lag index */
106        decode_absolute_lagIndex = 1;
107        if( condCoding == CODE_CONDITIONALLY && psDec->ec_prevSignalType == TYPE_VOICED ) {
108            /* Decode Delta index */
109            delta_lagIndex = (opus_int16)ec_dec_icdf( psRangeDec, silk_pitch_delta_iCDF, 8 );
110            if( delta_lagIndex > 0 ) {
111                delta_lagIndex = delta_lagIndex - 9;
112                psDec->indices.lagIndex = (opus_int16)( psDec->ec_prevLagIndex + delta_lagIndex );
113                decode_absolute_lagIndex = 0;
114            }
115        }
116        if( decode_absolute_lagIndex ) {
117            /* Absolute decoding */
118            psDec->indices.lagIndex  = (opus_int16)ec_dec_icdf( psRangeDec, silk_pitch_lag_iCDF, 8 ) * silk_RSHIFT( psDec->fs_kHz, 1 );
119            psDec->indices.lagIndex += (opus_int16)ec_dec_icdf( psRangeDec, psDec->pitch_lag_low_bits_iCDF, 8 );
120        }
121        psDec->ec_prevLagIndex = psDec->indices.lagIndex;
122
123        /* Get countour index */
124        psDec->indices.contourIndex = (opus_int8)ec_dec_icdf( psRangeDec, psDec->pitch_contour_iCDF, 8 );
125
126        /********************/
127        /* Decode LTP gains */
128        /********************/
129        /* Decode PERIndex value */
130        psDec->indices.PERIndex = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTP_per_index_iCDF, 8 );
131
132        for( k = 0; k < psDec->nb_subfr; k++ ) {
133            psDec->indices.LTPIndex[ k ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTP_gain_iCDF_ptrs[ psDec->indices.PERIndex ], 8 );
134        }
135
136        /**********************/
137        /* Decode LTP scaling */
138        /**********************/
139        if( condCoding == CODE_INDEPENDENTLY ) {
140            psDec->indices.LTP_scaleIndex = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTPscale_iCDF, 8 );
141        } else {
142            psDec->indices.LTP_scaleIndex = 0;
143        }
144    }
145    psDec->ec_prevSignalType = psDec->indices.signalType;
146
147    /***************/
148    /* Decode seed */
149    /***************/
150    psDec->indices.Seed = (opus_int8)ec_dec_icdf( psRangeDec, silk_uniform4_iCDF, 8 );
151}
152