ref: 222494f3ea66da5abb218508abf53dc40d13b99e
dir: /silk/silk_k2a.c/
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#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "silk_SigProc_FIX.h"
/* Step up function, converts reflection coefficients to prediction coefficients */
void silk_k2a(
opus_int32 *A_Q24, /* O: Prediction coefficients [order] Q24 */
const opus_int16 *rc_Q15, /* I: Reflection coefficients [order] Q15 */
const opus_int32 order /* I: Prediction order */
)
{
opus_int k, n;
opus_int32 Atmp[ SILK_MAX_ORDER_LPC ];
for( k = 0; k < order; k++ ) {
for( n = 0; n < k; n++ ) {
Atmp[ n ] = A_Q24[ n ];
}
for( n = 0; n < k; n++ ) {
A_Q24[ n ] = SKP_SMLAWB( A_Q24[ n ], SKP_LSHIFT( Atmp[ k - n - 1 ], 1 ), rc_Q15[ k ] );
}
A_Q24[ k ] = -SKP_LSHIFT( (opus_int32)rc_Q15[ k ], 9 );
}
}