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 "SigProc_FLP.h"
33*a58d3d2aSXin Li
34*a58d3d2aSXin Li /* Chirp (bw expand) LP AR filter */
silk_bwexpander_FLP(silk_float * ar,const opus_int d,const silk_float chirp)35*a58d3d2aSXin Li void silk_bwexpander_FLP(
36*a58d3d2aSXin Li silk_float *ar, /* I/O AR filter to be expanded (without leading 1) */
37*a58d3d2aSXin Li const opus_int d, /* I length of ar */
38*a58d3d2aSXin Li const silk_float chirp /* I chirp factor (typically in range (0..1) ) */
39*a58d3d2aSXin Li )
40*a58d3d2aSXin Li {
41*a58d3d2aSXin Li opus_int i;
42*a58d3d2aSXin Li silk_float cfac = chirp;
43*a58d3d2aSXin Li
44*a58d3d2aSXin Li for( i = 0; i < d - 1; i++ ) {
45*a58d3d2aSXin Li ar[ i ] *= cfac;
46*a58d3d2aSXin Li cfac *= chirp;
47*a58d3d2aSXin Li }
48*a58d3d2aSXin Li ar[ d - 1 ] *= cfac;
49*a58d3d2aSXin Li }
50