ref: 5413ef784941652448e703688fbe3b96ef6d7e86
dir: /silk/float/bwexpander_FLP.c/
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#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "SigProc_FLP.h"
/* Chirp (bw expand) LP AR filter */
void silk_bwexpander_FLP(
silk_float *ar, /* I/O AR filter to be expanded (without leading 1) */
const opus_int d, /* I length of ar */
const silk_float chirp /* I chirp factor (typically in range (0..1) ) */
)
{
opus_int i;
silk_float cfac = chirp;
for( i = 0; i < d - 1; i++ ) {
ar[ i ] *= cfac;
cfac *= chirp;
}
ar[ d - 1 ] *= cfac;
}