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 );
    }
}