diff options
Diffstat (limited to 'src/opus-1.1/silk/float/find_LTP_FLP.c')
| -rw-r--r-- | src/opus-1.1/silk/float/find_LTP_FLP.c | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/src/opus-1.1/silk/float/find_LTP_FLP.c b/src/opus-1.1/silk/float/find_LTP_FLP.c new file mode 100644 index 00000000..72299960 --- /dev/null +++ b/src/opus-1.1/silk/float/find_LTP_FLP.c @@ -0,0 +1,132 @@ +/*********************************************************************** +Copyright (c) 2006-2011, Skype Limited. All rights reserved. +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions +are met: +- Redistributions of source code must retain the above copyright notice, +this list of conditions and the following disclaimer. +- Redistributions in binary form must reproduce the above copyright +notice, this list of conditions and the following disclaimer in the +documentation and/or other materials provided with the distribution. +- Neither the name of Internet Society, IETF or IETF Trust, nor the +names of specific contributors, may be used to endorse or promote +products derived from this software without specific prior written +permission. +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" +AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE +LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +POSSIBILITY OF SUCH DAMAGE. +***********************************************************************/ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include "main_FLP.h" +#include "tuning_parameters.h" + +void silk_find_LTP_FLP( + silk_float b[ MAX_NB_SUBFR * LTP_ORDER ], /* O LTP coefs */ + silk_float WLTP[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ], /* O Weight for LTP quantization */ + silk_float *LTPredCodGain, /* O LTP coding gain */ + const silk_float r_lpc[], /* I LPC residual */ + const opus_int lag[ MAX_NB_SUBFR ], /* I LTP lags */ + const silk_float Wght[ MAX_NB_SUBFR ], /* I Weights */ + const opus_int subfr_length, /* I Subframe length */ + const opus_int nb_subfr, /* I number of subframes */ + const opus_int mem_offset /* I Number of samples in LTP memory */ +) +{ + opus_int i, k; + silk_float *b_ptr, temp, *WLTP_ptr; + silk_float LPC_res_nrg, LPC_LTP_res_nrg; + silk_float d[ MAX_NB_SUBFR ], m, g, delta_b[ LTP_ORDER ]; + silk_float w[ MAX_NB_SUBFR ], nrg[ MAX_NB_SUBFR ], regu; + silk_float Rr[ LTP_ORDER ], rr[ MAX_NB_SUBFR ]; + const silk_float *r_ptr, *lag_ptr; + + b_ptr = b; + WLTP_ptr = WLTP; + r_ptr = &r_lpc[ mem_offset ]; + for( k = 0; k < nb_subfr; k++ ) { + lag_ptr = r_ptr - ( lag[ k ] + LTP_ORDER / 2 ); + + silk_corrMatrix_FLP( lag_ptr, subfr_length, LTP_ORDER, WLTP_ptr ); + silk_corrVector_FLP( lag_ptr, r_ptr, subfr_length, LTP_ORDER, Rr ); + + rr[ k ] = ( silk_float )silk_energy_FLP( r_ptr, subfr_length ); + regu = 1.0f + rr[ k ] + + matrix_ptr( WLTP_ptr, 0, 0, LTP_ORDER ) + + matrix_ptr( WLTP_ptr, LTP_ORDER-1, LTP_ORDER-1, LTP_ORDER ); + regu *= LTP_DAMPING / 3; + silk_regularize_correlations_FLP( WLTP_ptr, &rr[ k ], regu, LTP_ORDER ); + silk_solve_LDL_FLP( WLTP_ptr, LTP_ORDER, Rr, b_ptr ); + + /* Calculate residual energy */ + nrg[ k ] = silk_residual_energy_covar_FLP( b_ptr, WLTP_ptr, Rr, rr[ k ], LTP_ORDER ); + + temp = Wght[ k ] / ( nrg[ k ] * Wght[ k ] + 0.01f * subfr_length ); + silk_scale_vector_FLP( WLTP_ptr, temp, LTP_ORDER * LTP_ORDER ); + w[ k ] = matrix_ptr( WLTP_ptr, LTP_ORDER / 2, LTP_ORDER / 2, LTP_ORDER ); + + r_ptr += subfr_length; + b_ptr += LTP_ORDER; + WLTP_ptr += LTP_ORDER * LTP_ORDER; + } + + /* Compute LTP coding gain */ + if( LTPredCodGain != NULL ) { + LPC_LTP_res_nrg = 1e-6f; + LPC_res_nrg = 0.0f; + for( k = 0; k < nb_subfr; k++ ) { + LPC_res_nrg += rr[ k ] * Wght[ k ]; + LPC_LTP_res_nrg += nrg[ k ] * Wght[ k ]; + } + + silk_assert( LPC_LTP_res_nrg > 0 ); + *LTPredCodGain = 3.0f * silk_log2( LPC_res_nrg / LPC_LTP_res_nrg ); + } + + /* Smoothing */ + /* d = sum( B, 1 ); */ + b_ptr = b; + for( k = 0; k < nb_subfr; k++ ) { + d[ k ] = 0; + for( i = 0; i < LTP_ORDER; i++ ) { + d[ k ] += b_ptr[ i ]; + } + b_ptr += LTP_ORDER; + } + /* m = ( w * d' ) / ( sum( w ) + 1e-3 ); */ + temp = 1e-3f; + for( k = 0; k < nb_subfr; k++ ) { + temp += w[ k ]; + } + m = 0; + for( k = 0; k < nb_subfr; k++ ) { + m += d[ k ] * w[ k ]; + } + m = m / temp; + + b_ptr = b; + for( k = 0; k < nb_subfr; k++ ) { + g = LTP_SMOOTHING / ( LTP_SMOOTHING + w[ k ] ) * ( m - d[ k ] ); + temp = 0; + for( i = 0; i < LTP_ORDER; i++ ) { + delta_b[ i ] = silk_max_float( b_ptr[ i ], 0.1f ); + temp += delta_b[ i ]; + } + temp = g / temp; + for( i = 0; i < LTP_ORDER; i++ ) { + b_ptr[ i ] = b_ptr[ i ] + delta_b[ i ] * temp; + } + b_ptr += LTP_ORDER; + } +} |