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 #define MAX_ITERATIONS_RESIDUAL_NRG 10 35 #define REGULARIZATION_FACTOR 1e-8f 36 37 /* Residual energy: nrg = wxx - 2 * wXx * c + c' * wXX * c */ 38 silk_float silk_residual_energy_covar_FLP( /* O Weighted residual energy */ 39 const silk_float *c, /* I Filter coefficients */ 40 silk_float *wXX, /* I/O Weighted correlation matrix, reg. out */ 41 const silk_float *wXx, /* I Weighted correlation vector */ 42 const silk_float wxx, /* I Weighted correlation value */ 43 const opus_int D /* I Dimension */ 44 ) 45 { 46 opus_int i, j, k; 47 silk_float tmp, nrg = 0.0f, regularization; 48 49 /* Safety checks */ 50 silk_assert( D >= 0 ); 51 52 regularization = REGULARIZATION_FACTOR * ( wXX[ 0 ] + wXX[ D * D - 1 ] ); 53 for( k = 0; k < MAX_ITERATIONS_RESIDUAL_NRG; k++ ) { 54 nrg = wxx; 55 56 tmp = 0.0f; 57 for( i = 0; i < D; i++ ) { 58 tmp += wXx[ i ] * c[ i ]; 59 } 60 nrg -= 2.0f * tmp; 61 62 /* compute c' * wXX * c, assuming wXX is symmetric */ 63 for( i = 0; i < D; i++ ) { 64 tmp = 0.0f; 65 for( j = i + 1; j < D; j++ ) { 66 tmp += matrix_c_ptr( wXX, i, j, D ) * c[ j ]; 67 } 68 nrg += c[ i ] * ( 2.0f * tmp + matrix_c_ptr( wXX, i, i, D ) * c[ i ] ); 69 } 70 if( nrg > 0 ) { 71 break; 72 } else { 73 /* Add white noise */ 74 for( i = 0; i < D; i++ ) { 75 matrix_c_ptr( wXX, i, i, D ) += regularization; 76 } 77 /* Increase noise for next run */ 78 regularization *= 2.0f; 79 } 80 } 81 if( k == MAX_ITERATIONS_RESIDUAL_NRG ) { 82 silk_assert( nrg == 0 ); 83 nrg = 1.0f; 84 } 85 86 return nrg; 87 } 88 89 /* Calculates residual energies of input subframes where all subframes have LPC_order */ 90 /* of preceding samples */ 91 void silk_residual_energy_FLP( 92 silk_float nrgs[ MAX_NB_SUBFR ], /* O Residual energy per subframe */ 93 const silk_float x[], /* I Input signal */ 94 silk_float a[ 2 ][ MAX_LPC_ORDER ], /* I AR coefs for each frame half */ 95 const silk_float gains[], /* I Quantization gains */ 96 const opus_int subfr_length, /* I Subframe length */ 97 const opus_int nb_subfr, /* I number of subframes */ 98 const opus_int LPC_order /* I LPC order */ 99 ) 100 { 101 opus_int shift; 102 silk_float *LPC_res_ptr, LPC_res[ ( MAX_FRAME_LENGTH + MAX_NB_SUBFR * MAX_LPC_ORDER ) / 2 ]; 103 104 LPC_res_ptr = LPC_res + LPC_order; 105 shift = LPC_order + subfr_length; 106 107 /* Filter input to create the LPC residual for each frame half, and measure subframe energies */ 108 silk_LPC_analysis_filter_FLP( LPC_res, a[ 0 ], x + 0 * shift, 2 * shift, LPC_order ); 109 nrgs[ 0 ] = ( silk_float )( gains[ 0 ] * gains[ 0 ] * silk_energy_FLP( LPC_res_ptr + 0 * shift, subfr_length ) ); 110 nrgs[ 1 ] = ( silk_float )( gains[ 1 ] * gains[ 1 ] * silk_energy_FLP( LPC_res_ptr + 1 * shift, subfr_length ) ); 111 112 if( nb_subfr == MAX_NB_SUBFR ) { 113 silk_LPC_analysis_filter_FLP( LPC_res, a[ 1 ], x + 2 * shift, 2 * shift, LPC_order ); 114 nrgs[ 2 ] = ( silk_float )( gains[ 2 ] * gains[ 2 ] * silk_energy_FLP( LPC_res_ptr + 0 * shift, subfr_length ) ); 115 nrgs[ 3 ] = ( silk_float )( gains[ 3 ] * gains[ 3 ] * silk_energy_FLP( LPC_res_ptr + 1 * shift, subfr_length ) ); 116 } 117 } 118
