ref: 8fe210f14b040880829682a9f3f90b02993b4a64
dir: /silk/fixed/k2a_Q16_FIX.c/
/***********************************************************************
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***********************************************************************/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "SigProc_FIX.h"
/* Step up function, converts reflection coefficients to prediction coefficients */
void silk_k2a_Q16(
opus_int32 *A_Q24, /* O Prediction coefficients [order] Q24 */
const opus_int32 *rc_Q16, /* I Reflection coefficients [order] Q16 */
const opus_int32 order /* I Prediction order */
)
{
opus_int k, n;
opus_int32 rc, tmp1, tmp2;
for( k = 0; k < order; k++ ) {
rc = rc_Q16[ k ];
for( n = 0; n < (k + 1) >> 1; n++ ) {
tmp1 = A_Q24[ n ];
tmp2 = A_Q24[ k - n - 1 ];
A_Q24[ n ] = silk_SMLAWW( tmp1, tmp2, rc );
A_Q24[ k - n - 1 ] = silk_SMLAWW( tmp2, tmp1, rc );
}
A_Q24[ k ] = -silk_LSHIFT( rc, 8 );
}
}