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 ***********************************************************************/

 #ifdef HAVE_CONFIG_H

 #include "config.h"

 #endif

 #include "main.h"

 /* Decode side-information parameters from payload */

 void silk_decode_indices(

     silk_decoder_state          *psDec,                         /* I/O  State                                       */

     ec_dec                      *psRangeDec,                    /* I/O  Compressor data structure                   */

     opus_int                    FrameIndex,                     /* I    Frame number                                */

     opus_int                    decode_LBRR,                    /* I    Flag indicating LBRR data is being decoded  */

     opus_int                    condCoding                      /* I    The type of conditional coding to use       */

 )

 {

     opus_int   i, k, Ix;

     opus_int   decode_absolute_lagIndex, delta_lagIndex;

     opus_int16 ec_ix[ MAX_LPC_ORDER ];

     opus_uint8 pred_Q8[ MAX_LPC_ORDER ];

     /*******************************************/

     /* Decode signal type and quantizer offset */

     /*******************************************/

     if( decode_LBRR || psDec->VAD_flags[ FrameIndex ] ) {

         Ix = ec_dec_icdf( psRangeDec, silk_type_offset_VAD_iCDF, 8 ) + 2;

     } else {

         Ix = ec_dec_icdf( psRangeDec, silk_type_offset_no_VAD_iCDF, 8 );

     }

     psDec->indices.signalType      = (opus_int8)silk_RSHIFT( Ix, 1 );

     psDec->indices.quantOffsetType = (opus_int8)( Ix & 1 );

     /****************/

     /* Decode gains */

     /****************/

     /* First subframe */

     if( condCoding == CODE_CONDITIONALLY ) {

         /* Conditional coding */

         psDec->indices.GainsIndices[ 0 ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_delta_gain_iCDF, 8 );

     } else {

         /* Independent coding, in two stages: MSB bits followed by 3 LSBs */

         psDec->indices.GainsIndices[ 0 ]  = (opus_int8)silk_LSHIFT( ec_dec_icdf( psRangeDec, silk_gain_iCDF[ psDec->indices.signalType ], 8 ), 3 );

         psDec->indices.GainsIndices[ 0 ] += (opus_int8)ec_dec_icdf( psRangeDec, silk_uniform8_iCDF, 8 );

     }

     /* Remaining subframes */

     for( i = 1; i < psDec->nb_subfr; i++ ) {

         psDec->indices.GainsIndices[ i ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_delta_gain_iCDF, 8 );

     }

     /**********************/

     /* Decode LSF Indices */

     /**********************/

     psDec->indices.NLSFIndices[ 0 ] = (opus_int8)ec_dec_icdf( psRangeDec, &psDec->psNLSF_CB->CB1_iCDF[ ( psDec->indices.signalType >> 1 ) * psDec->psNLSF_CB->nVectors ], 8 );

     silk_NLSF_unpack( ec_ix, pred_Q8, psDec->psNLSF_CB, psDec->indices.NLSFIndices[ 0 ] );

     silk_assert( psDec->psNLSF_CB->order == psDec->LPC_order );

     for( i = 0; i < psDec->psNLSF_CB->order; i++ ) {

         Ix = ec_dec_icdf( psRangeDec, &psDec->psNLSF_CB->ec_iCDF[ ec_ix[ i ] ], 8 );

         if( Ix == 0 ) {

             Ix -= ec_dec_icdf( psRangeDec, silk_NLSF_EXT_iCDF, 8 );

         } else if( Ix == 2 * NLSF_QUANT_MAX_AMPLITUDE ) {

             Ix += ec_dec_icdf( psRangeDec, silk_NLSF_EXT_iCDF, 8 );

         }

         psDec->indices.NLSFIndices[ i+1 ] = (opus_int8)( Ix - NLSF_QUANT_MAX_AMPLITUDE );

     }

     /* Decode LSF interpolation factor */

     if( psDec->nb_subfr == MAX_NB_SUBFR ) {

         psDec->indices.NLSFInterpCoef_Q2 = (opus_int8)ec_dec_icdf( psRangeDec, silk_NLSF_interpolation_factor_iCDF, 8 );

     } else {

         psDec->indices.NLSFInterpCoef_Q2 = 4;

     }

     if( psDec->indices.signalType == TYPE_VOICED )

     {

         /*********************/

         /* Decode pitch lags */

         /*********************/

         /* Get lag index */

         decode_absolute_lagIndex = 1;

         if( condCoding == CODE_CONDITIONALLY && psDec->ec_prevSignalType == TYPE_VOICED ) {

             /* Decode Delta index */

             delta_lagIndex = (opus_int16)ec_dec_icdf( psRangeDec, silk_pitch_delta_iCDF, 8 );

             if( delta_lagIndex > 0 ) {

                 delta_lagIndex = delta_lagIndex - 9;

                 psDec->indices.lagIndex = (opus_int16)( psDec->ec_prevLagIndex + delta_lagIndex );

                 decode_absolute_lagIndex = 0;

             }

         }

         if( decode_absolute_lagIndex ) {

             /* Absolute decoding */

             psDec->indices.lagIndex  = (opus_int16)ec_dec_icdf( psRangeDec, silk_pitch_lag_iCDF, 8 ) * silk_RSHIFT( psDec->fs_kHz, 1 );

             psDec->indices.lagIndex += (opus_int16)ec_dec_icdf( psRangeDec, psDec->pitch_lag_low_bits_iCDF, 8 );

         }

         psDec->ec_prevLagIndex = psDec->indices.lagIndex;

         /* Get countour index */

         psDec->indices.contourIndex = (opus_int8)ec_dec_icdf( psRangeDec, psDec->pitch_contour_iCDF, 8 );

         /********************/

         /* Decode LTP gains */

         /********************/

         /* Decode PERIndex value */

         psDec->indices.PERIndex = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTP_per_index_iCDF, 8 );

         for( k = 0; k < psDec->nb_subfr; k++ ) {

             psDec->indices.LTPIndex[ k ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTP_gain_iCDF_ptrs[ psDec->indices.PERIndex ], 8 );

         }

         /**********************/

         /* Decode LTP scaling */

         /**********************/

         if( condCoding == CODE_INDEPENDENTLY ) {

             psDec->indices.LTP_scaleIndex = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTPscale_iCDF, 8 );

         } else {

             psDec->indices.LTP_scaleIndex = 0;

         }

     }

     psDec->ec_prevSignalType = psDec->indices.signalType;

     /***************/

     /* Decode seed */

     /***************/

     psDec->indices.Seed = (opus_int8)ec_dec_icdf( psRangeDec, silk_uniform4_iCDF, 8 );

 }