The judgment unit (20) successively decides the horizontal resolution in the signal data memory (10) corresponding to the judged vertical resolution to be a horizontal resolution of the input video signal.

A signal data memory (10) stores a horizontal resolution corresponding to a vertical resolution for each of the vertical resolution of a video signal.

Predetermined samples are diagonally filtered and horizontal resolution information folded into the signal.

A conversion unit (30) converts the input video signal into an output video signal having the horizontal resolution and the vertical resolution decided by the judgment unit (20).

The horizontal resolution is only 30 m and the vertical accuracy is about 10 m.

Television images are broadcast today with different horizontal definitions and played back on equipment whose horizontal definition does not match that of the broadcast images.

An active picture with a 16:9 ratio is transmitted within a 4:3 picture ratio, with consequent reduced visual horizontal definition, by the ''letter-box'' process.