ref: fe5fe9e14b0abcc32178c0c65f98b1a44ef8eb23
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 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 ] = silk_SMLAWW( A_Q24[ n ], Atmp[ k - n - 1 ], rc_Q16[ k ] );
}
A_Q24[ k ] = -silk_LSHIFT( rc_Q16[ k ], 8 );
}
}