The present invention provides a digital copying method for preventing
complete copying by the use of digital copying. A data generating portion
includes a storage device which generates a plurality of digital copies
having mutually different amounts of effective information from original
digital data, and stores the set of digital content having the digital
copies encrypted different numbers of times in a memory. A digital output
portion decrypts the set of digital content retrieved from the memory a
prescribed number of times, making usable and outputting one of the
digital copies in the set of digital content. An analog output portion
extracts the digital copy that has been encrypted zero times from the set
of digital content, converts that copy to analog data, and outputs that
data.