xref: /aosp_15_r20/external/libopus/silk/float/find_LTP_FLP.c (revision a58d3d2adb790c104798cd88c8a3aff4fa8b82cc)
1*a58d3d2aSXin Li /***********************************************************************
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26*a58d3d2aSXin Li ***********************************************************************/
27*a58d3d2aSXin Li 
28*a58d3d2aSXin Li #ifdef HAVE_CONFIG_H
29*a58d3d2aSXin Li #include "config.h"
30*a58d3d2aSXin Li #endif
31*a58d3d2aSXin Li 
32*a58d3d2aSXin Li #include "main_FLP.h"
33*a58d3d2aSXin Li #include "tuning_parameters.h"
34*a58d3d2aSXin Li 
silk_find_LTP_FLP(silk_float XX[MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER],silk_float xX[MAX_NB_SUBFR * LTP_ORDER],const silk_float r_ptr[],const opus_int lag[MAX_NB_SUBFR],const opus_int subfr_length,const opus_int nb_subfr,int arch)35*a58d3d2aSXin Li void silk_find_LTP_FLP(
36*a58d3d2aSXin Li     silk_float                      XX[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ], /* O    Weight for LTP quantization         */
37*a58d3d2aSXin Li     silk_float                      xX[ MAX_NB_SUBFR * LTP_ORDER ],     /* O    Weight for LTP quantization                 */
38*a58d3d2aSXin Li     const silk_float                r_ptr[],                            /* I    LPC residual                                */
39*a58d3d2aSXin Li     const opus_int                  lag[ MAX_NB_SUBFR ],                /* I    LTP lags                                    */
40*a58d3d2aSXin Li     const opus_int                  subfr_length,                       /* I    Subframe length                             */
41*a58d3d2aSXin Li     const opus_int                  nb_subfr,                           /* I    number of subframes                         */
42*a58d3d2aSXin Li     int                             arch
43*a58d3d2aSXin Li )
44*a58d3d2aSXin Li {
45*a58d3d2aSXin Li     opus_int   k;
46*a58d3d2aSXin Li     silk_float *xX_ptr, *XX_ptr;
47*a58d3d2aSXin Li     const silk_float *lag_ptr;
48*a58d3d2aSXin Li     silk_float xx, temp;
49*a58d3d2aSXin Li 
50*a58d3d2aSXin Li     xX_ptr = xX;
51*a58d3d2aSXin Li     XX_ptr = XX;
52*a58d3d2aSXin Li     for( k = 0; k < nb_subfr; k++ ) {
53*a58d3d2aSXin Li         lag_ptr = r_ptr - ( lag[ k ] + LTP_ORDER / 2 );
54*a58d3d2aSXin Li         silk_corrMatrix_FLP( lag_ptr, subfr_length, LTP_ORDER, XX_ptr, arch );
55*a58d3d2aSXin Li         silk_corrVector_FLP( lag_ptr, r_ptr, subfr_length, LTP_ORDER, xX_ptr, arch );
56*a58d3d2aSXin Li         xx = ( silk_float )silk_energy_FLP( r_ptr, subfr_length + LTP_ORDER );
57*a58d3d2aSXin Li         temp = 1.0f / silk_max( xx, LTP_CORR_INV_MAX * 0.5f * ( XX_ptr[ 0 ] + XX_ptr[ 24 ] ) + 1.0f );
58*a58d3d2aSXin Li         silk_scale_vector_FLP( XX_ptr, temp, LTP_ORDER * LTP_ORDER );
59*a58d3d2aSXin Li         silk_scale_vector_FLP( xX_ptr, temp, LTP_ORDER );
60*a58d3d2aSXin Li 
61*a58d3d2aSXin Li         r_ptr  += subfr_length;
62*a58d3d2aSXin Li         XX_ptr += LTP_ORDER * LTP_ORDER;
63*a58d3d2aSXin Li         xX_ptr += LTP_ORDER;
64*a58d3d2aSXin Li     }
65*a58d3d2aSXin Li }
66