xref: /external/chromium_org/third_party/opus/src/silk/float/k2a_FLP.c

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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 Atmp[ SILK_MAX_ORDER_LPC ];

    for( k = 0; k < order; k++ ) {
        for( n = 0; n < k; n++ ) {
            Atmp[ n ] = A[ n ];
        }
        for( n = 0; n < k; n++ ) {
            A[ n ] += Atmp[ k - n - 1 ] * rc[ k ];
        }
        A[ k ] = -rc[ k ];
    }
}