diff options
Diffstat (limited to 'media/libopus/silk/float/find_LTP_FLP.c')
| -rw-r--r-- | media/libopus/silk/float/find_LTP_FLP.c | 108 |
1 files changed, 20 insertions, 88 deletions
diff --git a/media/libopus/silk/float/find_LTP_FLP.c b/media/libopus/silk/float/find_LTP_FLP.c index 7229996014..f97064930e 100644 --- a/media/libopus/silk/float/find_LTP_FLP.c +++ b/media/libopus/silk/float/find_LTP_FLP.c @@ -33,100 +33,32 @@ POSSIBILITY OF SUCH DAMAGE. #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 */ + 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 */ 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 */ + const opus_int nb_subfr /* I number of subframes */ ) { - 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; + opus_int k; + silk_float *xX_ptr, *XX_ptr; + const silk_float *lag_ptr; + silk_float xx, temp; - b_ptr = b; - WLTP_ptr = WLTP; - r_ptr = &r_lpc[ mem_offset ]; + xX_ptr = xX; + XX_ptr = XX; 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 ); - 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; + r_ptr += subfr_length; + XX_ptr += LTP_ORDER * LTP_ORDER; + xX_ptr += LTP_ORDER; } } |