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 #ifdef HAVE_CONFIG_H

 #include "config.h"

 #endif

 #include "main.h"

 /* Decode parameters from payload */

 void silk_decode_parameters(

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

     silk_decoder_control        *psDecCtrl,                     /* I/O  Decoder control                             */

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

 )

 {

     opus_int   i, k, Ix;

     opus_int16 pNLSF_Q15[ MAX_LPC_ORDER ], pNLSF0_Q15[ MAX_LPC_ORDER ];

     const opus_int8 *cbk_ptr_Q7;

     /* Dequant Gains */

     silk_gains_dequant( psDecCtrl->Gains_Q16, psDec->indices.GainsIndices,

         &psDec->LastGainIndex, condCoding == CODE_CONDITIONALLY, psDec->nb_subfr );

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

     /* Decode NLSFs */

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

     silk_NLSF_decode( pNLSF_Q15, psDec->indices.NLSFIndices, psDec->psNLSF_CB );

     /* Convert NLSF parameters to AR prediction filter coefficients */

     silk_NLSF2A( psDecCtrl->PredCoef_Q12[ 1 ], pNLSF_Q15, psDec->LPC_order );

     /* If just reset, e.g., because internal Fs changed, do not allow interpolation */

     /* improves the case of packet loss in the first frame after a switch           */

     if( psDec->first_frame_after_reset == 1 ) {

         psDec->indices.NLSFInterpCoef_Q2 = 4;

     }

     if( psDec->indices.NLSFInterpCoef_Q2 < 4 ) {

         /* Calculation of the interpolated NLSF0 vector from the interpolation factor, */

         /* the previous NLSF1, and the current NLSF1                                   */

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

             pNLSF0_Q15[ i ] = psDec->prevNLSF_Q15[ i ] + silk_RSHIFT( silk_MUL( psDec->indices.NLSFInterpCoef_Q2,

                 pNLSF_Q15[ i ] - psDec->prevNLSF_Q15[ i ] ), 2 );

         }

         /* Convert NLSF parameters to AR prediction filter coefficients */

         silk_NLSF2A( psDecCtrl->PredCoef_Q12[ 0 ], pNLSF0_Q15, psDec->LPC_order );

     } else {

         /* Copy LPC coefficients for first half from second half */

         silk_memcpy( psDecCtrl->PredCoef_Q12[ 0 ], psDecCtrl->PredCoef_Q12[ 1 ], psDec->LPC_order * sizeof( opus_int16 ) );

     }

     silk_memcpy( psDec->prevNLSF_Q15, pNLSF_Q15, psDec->LPC_order * sizeof( opus_int16 ) );

     /* After a packet loss do BWE of LPC coefs */

     if( psDec->lossCnt ) {

         silk_bwexpander( psDecCtrl->PredCoef_Q12[ 0 ], psDec->LPC_order, BWE_AFTER_LOSS_Q16 );

         silk_bwexpander( psDecCtrl->PredCoef_Q12[ 1 ], psDec->LPC_order, BWE_AFTER_LOSS_Q16 );

     }

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

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

         /* Decode pitch lags */

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

         /* Decode pitch values */

         silk_decode_pitch( psDec->indices.lagIndex, psDec->indices.contourIndex, psDecCtrl->pitchL, psDec->fs_kHz, psDec->nb_subfr );

         /* Decode Codebook Index */

         cbk_ptr_Q7 = silk_LTP_vq_ptrs_Q7[ psDec->indices.PERIndex ]; /* set pointer to start of codebook */

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

             Ix = psDec->indices.LTPIndex[ k ];

             for( i = 0; i < LTP_ORDER; i++ ) {

                 psDecCtrl->LTPCoef_Q14[ k * LTP_ORDER + i ] = silk_LSHIFT( cbk_ptr_Q7[ Ix * LTP_ORDER + i ], 7 );

             }

         }

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

         /* Decode LTP scaling */

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

         Ix = psDec->indices.LTP_scaleIndex;

         psDecCtrl->LTP_scale_Q14 = silk_LTPScales_table_Q14[ Ix ];

     } else {

         silk_memset( psDecCtrl->pitchL,      0,             psDec->nb_subfr * sizeof( opus_int   ) );

         silk_memset( psDecCtrl->LTPCoef_Q14, 0, LTP_ORDER * psDec->nb_subfr * sizeof( opus_int16 ) );

         psDec->indices.PERIndex  = 0;

         psDecCtrl->LTP_scale_Q14 = 0;

     }

 }