ioef/code/opus-1.1/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;
}