diff options
Diffstat (limited to 'thirdparty/opus/silk/float/find_LTP_FLP.c')
| -rw-r--r-- | thirdparty/opus/silk/float/find_LTP_FLP.c | 108 |
1 files changed, 88 insertions, 20 deletions
diff --git a/thirdparty/opus/silk/float/find_LTP_FLP.c b/thirdparty/opus/silk/float/find_LTP_FLP.c index f97064930e..7229996014 100644 --- a/thirdparty/opus/silk/float/find_LTP_FLP.c +++ b/thirdparty/opus/silk/float/find_LTP_FLP.c @@ -33,32 +33,100 @@ POSSIBILITY OF SUCH DAMAGE. #include "tuning_parameters.h" void silk_find_LTP_FLP( - silk_float XX[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ], /* O Weight for LTP quantization */ - silk_float xX[ MAX_NB_SUBFR * LTP_ORDER ], /* O Weight for LTP quantization */ - const silk_float r_ptr[], /* I LPC residual */ - const opus_int lag[ MAX_NB_SUBFR ], /* I LTP lags */ + 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 nb_subfr, /* I number of subframes */ + const opus_int mem_offset /* I Number of samples in LTP memory */ ) { - opus_int k; - silk_float *xX_ptr, *XX_ptr; - const silk_float *lag_ptr; - silk_float xx, temp; + 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; - xX_ptr = xX; - XX_ptr = XX; + 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, XX_ptr ); - silk_corrVector_FLP( lag_ptr, r_ptr, subfr_length, LTP_ORDER, xX_ptr ); - xx = ( silk_float )silk_energy_FLP( r_ptr, subfr_length + LTP_ORDER ); - temp = 1.0f / silk_max( xx, LTP_CORR_INV_MAX * 0.5f * ( XX_ptr[ 0 ] + XX_ptr[ 24 ] ) + 1.0f ); - silk_scale_vector_FLP( XX_ptr, temp, LTP_ORDER * LTP_ORDER ); - silk_scale_vector_FLP( xX_ptr, temp, LTP_ORDER ); - r_ptr += subfr_length; - XX_ptr += LTP_ORDER * LTP_ORDER; - xX_ptr += LTP_ORDER; + 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; } } |