Multimode interpolation filter as for a TV receiver

This invention relates to an interpolator for scan converting decompressed video signal occurring in a plurality of alternative formats. A multimode scan converter includes a delay element () for delaying one horizontal line of video signal and selectively re-displaying that line. A multiplexer () is arranged to selectively provide either luminance signal or chrominance signal to the delay element. Output signal from the delay element and output signal from the multiplexer are coupled to a proportioning circuit () which sums the two signals in complementary proportions (e.g. K and 1-K). A second multiplexer (), which provides up-converted output luminance signal, is arranged to selectively pass the luminance signal or signal from the proportioning circuit. A third multiplexer (), which provides up-converted output chrominance signal, is arranged to selectively pass the chrominance signal or signal from the proportioning circuit.