opus/silk/interpolate.c

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#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "main.h"

/* Interpolate two vectors */
void silk_interpolate(
    opus_int16                  xi[ MAX_LPC_ORDER ],            /* O    interpolated vector                         */
    const opus_int16            x0[ MAX_LPC_ORDER ],            /* I    first vector                                */
    const opus_int16            x1[ MAX_LPC_ORDER ],            /* I    second vector                               */
    const opus_int              ifact_Q2,                       /* I    interp. factor, weight on 2nd vector        */
    const opus_int              d                               /* I    number of parameters                        */
)
{
    opus_int i;

    silk_assert( ifact_Q2 >= 0 );
    silk_assert( ifact_Q2 <= 4 );

    for( i = 0; i < d; i++ ) {
        xi[ i ] = (opus_int16)silk_ADD_RSHIFT( x0[ i ], silk_SMULBB( x1[ i ] - x0[ i ], ifact_Q2 ), 2 );
    }
}