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      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.h"
     33 
     34 /* Decode side-information parameters from payload */
     35 void 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