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26***********************************************************************/
27
28#ifdef HAVE_CONFIG_H
29#include "config.h"
30#endif
31
32#include "main_FLP.h"
33
34/* Find LPC and LTP coefficients */
35void silk_find_pred_coefs_FLP(
36    silk_encoder_state_FLP          *psEnc,                             /* I/O  Encoder state FLP                           */
37    silk_encoder_control_FLP        *psEncCtrl,                         /* I/O  Encoder control FLP                         */
38    const silk_float                res_pitch[],                        /* I    Residual from pitch analysis                */
39    const silk_float                x[],                                /* I    Speech signal                               */
40    opus_int                        condCoding                          /* I    The type of conditional coding to use       */
41)
42{
43    opus_int         i;
44    silk_float       WLTP[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ];
45    silk_float       invGains[ MAX_NB_SUBFR ], Wght[ MAX_NB_SUBFR ];
46    opus_int16       NLSF_Q15[ MAX_LPC_ORDER ];
47    const silk_float *x_ptr;
48    silk_float       *x_pre_ptr, LPC_in_pre[ MAX_NB_SUBFR * MAX_LPC_ORDER + MAX_FRAME_LENGTH ];
49    silk_float       minInvGain;
50
51    /* Weighting for weighted least squares */
52    for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {
53        silk_assert( psEncCtrl->Gains[ i ] > 0.0f );
54        invGains[ i ] = 1.0f / psEncCtrl->Gains[ i ];
55        Wght[ i ]     = invGains[ i ] * invGains[ i ];
56    }
57
58    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
59        /**********/
60        /* VOICED */
61        /**********/
62        silk_assert( psEnc->sCmn.ltp_mem_length - psEnc->sCmn.predictLPCOrder >= psEncCtrl->pitchL[ 0 ] + LTP_ORDER / 2 );
63
64        /* LTP analysis */
65        silk_find_LTP_FLP( psEncCtrl->LTPCoef, WLTP, &psEncCtrl->LTPredCodGain, res_pitch,
66            psEncCtrl->pitchL, Wght, psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.ltp_mem_length );
67
68        /* Quantize LTP gain parameters */
69        silk_quant_LTP_gains_FLP( psEncCtrl->LTPCoef, psEnc->sCmn.indices.LTPIndex, &psEnc->sCmn.indices.PERIndex,
70            &psEnc->sCmn.sum_log_gain_Q7, WLTP, psEnc->sCmn.mu_LTP_Q9, psEnc->sCmn.LTPQuantLowComplexity, psEnc->sCmn.nb_subfr );
71
72        /* Control LTP scaling */
73        silk_LTP_scale_ctrl_FLP( psEnc, psEncCtrl, condCoding );
74
75        /* Create LTP residual */
76        silk_LTP_analysis_filter_FLP( LPC_in_pre, x - psEnc->sCmn.predictLPCOrder, psEncCtrl->LTPCoef,
77            psEncCtrl->pitchL, invGains, psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.predictLPCOrder );
78    } else {
79        /************/
80        /* UNVOICED */
81        /************/
82        /* Create signal with prepended subframes, scaled by inverse gains */
83        x_ptr     = x - psEnc->sCmn.predictLPCOrder;
84        x_pre_ptr = LPC_in_pre;
85        for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {
86            silk_scale_copy_vector_FLP( x_pre_ptr, x_ptr, invGains[ i ],
87                psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder );
88            x_pre_ptr += psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder;
89            x_ptr     += psEnc->sCmn.subfr_length;
90        }
91        silk_memset( psEncCtrl->LTPCoef, 0, psEnc->sCmn.nb_subfr * LTP_ORDER * sizeof( silk_float ) );
92        psEncCtrl->LTPredCodGain = 0.0f;
93		psEnc->sCmn.sum_log_gain_Q7 = 0;
94    }
95
96    /* Limit on total predictive coding gain */
97    if( psEnc->sCmn.first_frame_after_reset ) {
98        minInvGain = 1.0f / MAX_PREDICTION_POWER_GAIN_AFTER_RESET;
99    } else {
100        minInvGain = (silk_float)pow( 2, psEncCtrl->LTPredCodGain / 3 ) /  MAX_PREDICTION_POWER_GAIN;
101        minInvGain /= 0.25f + 0.75f * psEncCtrl->coding_quality;
102    }
103
104    /* LPC_in_pre contains the LTP-filtered input for voiced, and the unfiltered input for unvoiced */
105    silk_find_LPC_FLP( &psEnc->sCmn, NLSF_Q15, LPC_in_pre, minInvGain );
106
107    /* Quantize LSFs */
108    silk_process_NLSFs_FLP( &psEnc->sCmn, psEncCtrl->PredCoef, NLSF_Q15, psEnc->sCmn.prev_NLSFq_Q15 );
109
110    /* Calculate residual energy using quantized LPC coefficients */
111    silk_residual_energy_FLP( psEncCtrl->ResNrg, LPC_in_pre, psEncCtrl->PredCoef, psEncCtrl->Gains,
112        psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.predictLPCOrder );
113
114    /* Copy to prediction struct for use in next frame for interpolation */
115    silk_memcpy( psEnc->sCmn.prev_NLSFq_Q15, NLSF_Q15, sizeof( psEnc->sCmn.prev_NLSFq_Q15 ) );
116}
117
118