tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

find_pred_coefs_FLP.c (6078B)


      1 /***********************************************************************
      2 Copyright (c) 2006-2011, Skype Limited. All rights reserved.
      3 Redistribution and use in source and binary forms, with or without
      4 modification, are permitted provided that the following conditions
      5 are met:
      6 - Redistributions of source code must retain the above copyright notice,
      7 this list of conditions and the following disclaimer.
      8 - Redistributions in binary form must reproduce the above copyright
      9 notice, this list of conditions and the following disclaimer in the
     10 documentation and/or other materials provided with the distribution.
     11 - Neither the name of Internet Society, IETF or IETF Trust, nor the
     12 names of specific contributors, may be used to endorse or promote
     13 products derived from this software without specific prior written
     14 permission.
     15 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
     16 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     17 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     18 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
     19 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     20 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     21 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     22 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     23 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     24 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     25 POSSIBILITY OF SUCH DAMAGE.
     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 */
     35 void 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       XXLTP[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ];
     45    silk_float       xXLTP[ MAX_NB_SUBFR * LTP_ORDER ];
     46    silk_float       invGains[ MAX_NB_SUBFR ];
     47    /* Set to NLSF_Q15 to zero so we don't copy junk to the state. */
     48    opus_int16       NLSF_Q15[ MAX_LPC_ORDER ]={0};
     49    const silk_float *x_ptr;
     50    silk_float       *x_pre_ptr, LPC_in_pre[ MAX_NB_SUBFR * MAX_LPC_ORDER + MAX_FRAME_LENGTH ];
     51    silk_float       minInvGain;
     52 
     53    /* Weighting for weighted least squares */
     54    for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {
     55        silk_assert( psEncCtrl->Gains[ i ] > 0.0f );
     56        invGains[ i ] = 1.0f / psEncCtrl->Gains[ i ];
     57    }
     58 
     59    if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
     60        /**********/
     61        /* VOICED */
     62        /**********/
     63        celt_assert( psEnc->sCmn.ltp_mem_length - psEnc->sCmn.predictLPCOrder >= psEncCtrl->pitchL[ 0 ] + LTP_ORDER / 2 );
     64 
     65        /* LTP analysis */
     66        silk_find_LTP_FLP( XXLTP, xXLTP, res_pitch, psEncCtrl->pitchL, psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.arch );
     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, &psEncCtrl->LTPredCodGain, XXLTP, xXLTP, psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.arch );
     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, psEnc->sCmn.arch );
    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 }