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 #ifdef HAVE_CONFIG_H

 #include "config.h"

 #endif

 #include "main.h"

 #include "stack_alloc.h"

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

 /* NLSF vector encoder */

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

 opus_int32 silk_NLSF_encode(                                    /* O    Returns RD value in Q25                     */

           opus_int8             *NLSFIndices,                   /* I    Codebook path vector [ LPC_ORDER + 1 ]      */

           opus_int16            *pNLSF_Q15,                     /* I/O  Quantized NLSF vector [ LPC_ORDER ]         */

     const silk_NLSF_CB_struct   *psNLSF_CB,                     /* I    Codebook object                             */

     const opus_int16            *pW_QW,                         /* I    NLSF weight vector [ LPC_ORDER ]            */

     const opus_int              NLSF_mu_Q20,                    /* I    Rate weight for the RD optimization         */

     const opus_int              nSurvivors,                     /* I    Max survivors after first stage             */

     const opus_int              signalType                      /* I    Signal type: 0/1/2                          */

 )

 {

     opus_int         i, s, ind1, bestIndex, prob_Q8, bits_q7;

     opus_int32       W_tmp_Q9;

     VARDECL( opus_int32, err_Q26 );

     VARDECL( opus_int32, RD_Q25 );

     VARDECL( opus_int, tempIndices1 );

     VARDECL( opus_int8, tempIndices2 );

     opus_int16       res_Q15[      MAX_LPC_ORDER ];

     opus_int16       res_Q10[      MAX_LPC_ORDER ];

     opus_int16       NLSF_tmp_Q15[ MAX_LPC_ORDER ];

     opus_int16       W_tmp_QW[     MAX_LPC_ORDER ];

     opus_int16       W_adj_Q5[     MAX_LPC_ORDER ];

     opus_uint8       pred_Q8[      MAX_LPC_ORDER ];

     opus_int16       ec_ix[        MAX_LPC_ORDER ];

     const opus_uint8 *pCB_element, *iCDF_ptr;

     SAVE_STACK;

     silk_assert( nSurvivors <= NLSF_VQ_MAX_SURVIVORS );

     silk_assert( signalType >= 0 && signalType <= 2 );

     silk_assert( NLSF_mu_Q20 <= 32767 && NLSF_mu_Q20 >= 0 );

     /* NLSF stabilization */

     silk_NLSF_stabilize( pNLSF_Q15, psNLSF_CB->deltaMin_Q15, psNLSF_CB->order );

     /* First stage: VQ */

     ALLOC( err_Q26, psNLSF_CB->nVectors, opus_int32 );

     silk_NLSF_VQ( err_Q26, pNLSF_Q15, psNLSF_CB->CB1_NLSF_Q8, psNLSF_CB->nVectors, psNLSF_CB->order );

     /* Sort the quantization errors */

     ALLOC( tempIndices1, nSurvivors, opus_int );

     silk_insertion_sort_increasing( err_Q26, tempIndices1, psNLSF_CB->nVectors, nSurvivors );

     ALLOC( RD_Q25, nSurvivors, opus_int32 );

     ALLOC( tempIndices2, nSurvivors * MAX_LPC_ORDER, opus_int8 );

     /* Loop over survivors */

     for( s = 0; s < nSurvivors; s++ ) {

         ind1 = tempIndices1[ s ];

         /* Residual after first stage */

         pCB_element = &psNLSF_CB->CB1_NLSF_Q8[ ind1 * psNLSF_CB->order ];

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

             NLSF_tmp_Q15[ i ] = silk_LSHIFT16( (opus_int16)pCB_element[ i ], 7 );

             res_Q15[ i ] = pNLSF_Q15[ i ] - NLSF_tmp_Q15[ i ];

         }

         /* Weights from codebook vector */

         silk_NLSF_VQ_weights_laroia( W_tmp_QW, NLSF_tmp_Q15, psNLSF_CB->order );

         /* Apply square-rooted weights */

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

             W_tmp_Q9 = silk_SQRT_APPROX( silk_LSHIFT( (opus_int32)W_tmp_QW[ i ], 18 - NLSF_W_Q ) );

             res_Q10[ i ] = (opus_int16)silk_RSHIFT( silk_SMULBB( res_Q15[ i ], W_tmp_Q9 ), 14 );

         }

         /* Modify input weights accordingly */

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

             W_adj_Q5[ i ] = silk_DIV32_16( silk_LSHIFT( (opus_int32)pW_QW[ i ], 5 ), W_tmp_QW[ i ] );

         }

         /* Unpack entropy table indices and predictor for current CB1 index */

         silk_NLSF_unpack( ec_ix, pred_Q8, psNLSF_CB, ind1 );

         /* Trellis quantizer */

         RD_Q25[ s ] = silk_NLSF_del_dec_quant( &tempIndices2[ s * MAX_LPC_ORDER ], res_Q10, W_adj_Q5, pred_Q8, ec_ix,

             psNLSF_CB->ec_Rates_Q5, psNLSF_CB->quantStepSize_Q16, psNLSF_CB->invQuantStepSize_Q6, NLSF_mu_Q20, psNLSF_CB->order );

         /* Add rate for first stage */

         iCDF_ptr = &psNLSF_CB->CB1_iCDF[ ( signalType >> 1 ) * psNLSF_CB->nVectors ];

         if( ind1 == 0 ) {

             prob_Q8 = 256 - iCDF_ptr[ ind1 ];

         } else {

             prob_Q8 = iCDF_ptr[ ind1 - 1 ] - iCDF_ptr[ ind1 ];

         }

         bits_q7 = ( 8 << 7 ) - silk_lin2log( prob_Q8 );

         RD_Q25[ s ] = silk_SMLABB( RD_Q25[ s ], bits_q7, silk_RSHIFT( NLSF_mu_Q20, 2 ) );

     }

     /* Find the lowest rate-distortion error */

     silk_insertion_sort_increasing( RD_Q25, &bestIndex, nSurvivors, 1 );

     NLSFIndices[ 0 ] = (opus_int8)tempIndices1[ bestIndex ];

     silk_memcpy( &NLSFIndices[ 1 ], &tempIndices2[ bestIndex * MAX_LPC_ORDER ], psNLSF_CB->order * sizeof( opus_int8 ) );

     /* Decode */

     silk_NLSF_decode( pNLSF_Q15, NLSFIndices, psNLSF_CB );

     RESTORE_STACK;

     return RD_Q25[ 0 ];

 }