ref: f8ed894b1fb681109abc73ba75b3d6237a751d72
dir: /silk/float/k2a_FLP.c/
/***********************************************************************
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "SigProc_FLP.h"
/* step up function, converts reflection coefficients to prediction coefficients */
void silk_k2a_FLP(
silk_float *A, /* O prediction coefficients [order] */
const silk_float *rc, /* I reflection coefficients [order] */
opus_int32 order /* I prediction order */
)
{
opus_int k, n;
silk_float rck, tmp1, tmp2;
for( k = 0; k < order; k++ ) {
rck = rc[ k ];
for( n = 0; n < (k + 1) >> 1; n++ ) {
tmp1 = A[ n ];
tmp2 = A[ k - n - 1 ];
A[ n ] = tmp1 + tmp2 * rck;
A[ k - n - 1 ] = tmp2 + tmp1 * rck;
}
A[ k ] = -rck;
}
}