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 #ifdef HAVE_CONFIG_H

 #include "config.h"

 #endif

 #include "main_FIX.h"

 #include "tuning_parameters.h"

 /* Processing of gains */

 void silk_process_gains_FIX(

     silk_encoder_state_FIX          *psEnc,                                 /* I/O  Encoder state                                                               */

     silk_encoder_control_FIX        *psEncCtrl,                             /* I/O  Encoder control                                                             */

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

 )

 {

     silk_shape_state_FIX *psShapeSt = &psEnc->sShape;

     opus_int     k;

     opus_int32   s_Q16, InvMaxSqrVal_Q16, gain, gain_squared, ResNrg, ResNrgPart, quant_offset_Q10;

     /* Gain reduction when LTP coding gain is high */

     if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {

         /*s = -0.5f * silk_sigmoid( 0.25f * ( psEncCtrl->LTPredCodGain - 12.0f ) ); */

         s_Q16 = -silk_sigm_Q15( silk_RSHIFT_ROUND( psEncCtrl->LTPredCodGain_Q7 - SILK_FIX_CONST( 12.0, 7 ), 4 ) );

         for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {

             psEncCtrl->Gains_Q16[ k ] = silk_SMLAWB( psEncCtrl->Gains_Q16[ k ], psEncCtrl->Gains_Q16[ k ], s_Q16 );

         }

     }

     /* Limit the quantized signal */

     /* InvMaxSqrVal = pow( 2.0f, 0.33f * ( 21.0f - SNR_dB ) ) / subfr_length; */

     InvMaxSqrVal_Q16 = silk_DIV32_16( silk_log2lin(

         silk_SMULWB( SILK_FIX_CONST( 21 + 16 / 0.33, 7 ) - psEnc->sCmn.SNR_dB_Q7, SILK_FIX_CONST( 0.33, 16 ) ) ), psEnc->sCmn.subfr_length );

     for( k = 0; k < psEnc->sCmn.nb_subfr; k++ ) {

         /* Soft limit on ratio residual energy and squared gains */

         ResNrg     = psEncCtrl->ResNrg[ k ];

         ResNrgPart = silk_SMULWW( ResNrg, InvMaxSqrVal_Q16 );

         if( psEncCtrl->ResNrgQ[ k ] > 0 ) {

             ResNrgPart = silk_RSHIFT_ROUND( ResNrgPart, psEncCtrl->ResNrgQ[ k ] );

         } else {

             if( ResNrgPart >= silk_RSHIFT( silk_int32_MAX, -psEncCtrl->ResNrgQ[ k ] ) ) {

                 ResNrgPart = silk_int32_MAX;

             } else {

                 ResNrgPart = silk_LSHIFT( ResNrgPart, -psEncCtrl->ResNrgQ[ k ] );

             }

         }

         gain = psEncCtrl->Gains_Q16[ k ];

         gain_squared = silk_ADD_SAT32( ResNrgPart, silk_SMMUL( gain, gain ) );

         if( gain_squared < silk_int16_MAX ) {

             /* recalculate with higher precision */

             gain_squared = silk_SMLAWW( silk_LSHIFT( ResNrgPart, 16 ), gain, gain );

             silk_assert( gain_squared > 0 );

             gain = silk_SQRT_APPROX( gain_squared );                    /* Q8   */

             gain = silk_min( gain, silk_int32_MAX >> 8 );

             psEncCtrl->Gains_Q16[ k ] = silk_LSHIFT_SAT32( gain, 8 );   /* Q16  */

         } else {

             gain = silk_SQRT_APPROX( gain_squared );                    /* Q0   */

             gain = silk_min( gain, silk_int32_MAX >> 16 );

             psEncCtrl->Gains_Q16[ k ] = silk_LSHIFT_SAT32( gain, 16 );  /* Q16  */

         }

     }

     /* Save unquantized gains and gain Index */

     silk_memcpy( psEncCtrl->GainsUnq_Q16, psEncCtrl->Gains_Q16, psEnc->sCmn.nb_subfr * sizeof( opus_int32 ) );

     psEncCtrl->lastGainIndexPrev = psShapeSt->LastGainIndex;

     /* Quantize gains */

     silk_gains_quant( psEnc->sCmn.indices.GainsIndices, psEncCtrl->Gains_Q16,

         &psShapeSt->LastGainIndex, condCoding == CODE_CONDITIONALLY, psEnc->sCmn.nb_subfr );

     /* Set quantizer offset for voiced signals. Larger offset when LTP coding gain is low or tilt is high (ie low-pass) */

     if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {

         if( psEncCtrl->LTPredCodGain_Q7 + silk_RSHIFT( psEnc->sCmn.input_tilt_Q15, 8 ) > SILK_FIX_CONST( 1.0, 7 ) ) {

             psEnc->sCmn.indices.quantOffsetType = 0;

         } else {

             psEnc->sCmn.indices.quantOffsetType = 1;

         }

     }

     /* Quantizer boundary adjustment */

     quant_offset_Q10 = silk_Quantization_Offsets_Q10[ psEnc->sCmn.indices.signalType >> 1 ][ psEnc->sCmn.indices.quantOffsetType ];

     psEncCtrl->Lambda_Q10 = SILK_FIX_CONST( LAMBDA_OFFSET, 10 )

                           + silk_SMULBB( SILK_FIX_CONST( LAMBDA_DELAYED_DECISIONS, 10 ), psEnc->sCmn.nStatesDelayedDecision )

                           + silk_SMULWB( SILK_FIX_CONST( LAMBDA_SPEECH_ACT,        18 ), psEnc->sCmn.speech_activity_Q8     )

                           + silk_SMULWB( SILK_FIX_CONST( LAMBDA_INPUT_QUALITY,     12 ), psEncCtrl->input_quality_Q14       )

                           + silk_SMULWB( SILK_FIX_CONST( LAMBDA_CODING_QUALITY,    12 ), psEncCtrl->coding_quality_Q14      )

                           + silk_SMULWB( SILK_FIX_CONST( LAMBDA_QUANT_OFFSET,      16 ), quant_offset_Q10                   );

     silk_assert( psEncCtrl->Lambda_Q10 > 0 );

     silk_assert( psEncCtrl->Lambda_Q10 < SILK_FIX_CONST( 2, 10 ) );

 }