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 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 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 } 94 95 /* Limit on total predictive coding gain */ 96 if( psEnc->sCmn.first_frame_after_reset ) { 97 minInvGain = 1.0f / MAX_PREDICTION_POWER_GAIN_AFTER_RESET; 98 } else { 99 minInvGain = (silk_float)pow( 2, psEncCtrl->LTPredCodGain / 3 ) / MAX_PREDICTION_POWER_GAIN; 100 minInvGain /= 0.25f + 0.75f * psEncCtrl->coding_quality; 101 } 102 103 /* LPC_in_pre contains the LTP-filtered input for voiced, and the unfiltered input for unvoiced */ 104 silk_find_LPC_FLP( &psEnc->sCmn, NLSF_Q15, LPC_in_pre, minInvGain ); 105 106 /* Quantize LSFs */ 107 silk_process_NLSFs_FLP( &psEnc->sCmn, psEncCtrl->PredCoef, NLSF_Q15, psEnc->sCmn.prev_NLSFq_Q15 ); 108 109 /* Calculate residual energy using quantized LPC coefficients */ 110 silk_residual_energy_FLP( psEncCtrl->ResNrg, LPC_in_pre, psEncCtrl->PredCoef, psEncCtrl->Gains, 111 psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.predictLPCOrder ); 112 113 /* Copy to prediction struct for use in next frame for interpolation */ 114 silk_memcpy( psEnc->sCmn.prev_NLSFq_Q15, NLSF_Q15, sizeof( psEnc->sCmn.prev_NLSFq_Q15 ) ); 115 } 116 117
