When digital image signals inputted through an inputting terminal are recorded on a disc, a medium-related information (a serial number in an TOC) of the disc, read from the disc, with a medium-related information reading section is spectrum-spread in an SS additional information generating section and then digital image signals S2 on which the spectrum-spread medium-related information is superimposed in an SS additional information superimposing section are recorded on the disc. When the signals attempt to be reproduced, the reproduction can be performed in the case wherein the medium-related information superimposed on the image signals recorded on the disc is consistent with the medium-related information of the disc on which the image signals are recorded. Thus, copying of the information signals can be limited to the copying for private use.