Processing high definition video signals

A digital video tape recorder (3), which reproduces from a record medium a digital high definition video signal having copy-prevention data therein, extracts the copy-prevention data from the reproduced signal (5), generates from the extracted digital copy-prevention data an analog copy-inhibit signal that has the same data format as a copy-inhibit signal superimposed on a standard definition video signal (6), converts the reproduced digital high definition video signal to an analog signal, and superimposes the analog copy-inhibit signal onto the analog signal for output (4). To record a high definition video signal, the digital video tape recorder (13) receives an analog high definition video signal that has superimposed thereon a copy-inhibit signal having the same data format as a copy-inhibit signal superimposed on a standard definition video signal, extracts the copy-inhibit signal from the received analog high definition video signal (16), supplies the received analog high definition video signal when that signal is not copy-protected, converts the supplied video signal to a digital signal, generates digital copy-prevention data from the extracted copy-inhibit signal (15), adds the digital copy-prevention data to the digital signal, and records on a record medium the digital signal with the digital copy-prevention data added thereto.