VIDEO DUPLICATION CONTROL SYSTEM, VIDEO PLAYBACK DEVICE, VIDEO RECORDING DEVICE, INFORMATION SUPERIMPOSING AND EXTRACTING DEVICE, AND VIDEO RECORDING MEDIUM

摘要

A PLAYBACK DEVICE (10) GENERATES A PN CODE (15) WITH A START TIMING BASED ON A VIDEO SYNC SIGNAL (14), AND GENERATES A PN INVERSE CODE (16) WHICH HAS A REVERSE POLARITY TO THAT OF THE PN CODE WITH A TIMING BASED ON THE VIDEO SYNC SIGNAL (14). AN ANTI-DUPLICATION CONTROL SIGNAL (13) IS SPECTRALLY SPREAD (17) USING THIS PN CODE, SUPERIMPOSED ON THE VIDEO SIGNAL (18) AND SUPPLIED TO A RECORDING DEVICE. A PN INVERSE CODE WHICH IS THE SAME AS THE PN INVERSE CODE USED IN THE PLAYBACK DEVICE IS ALSO GENERATED IN THE RECORDING DEVICE BASED ON THE VIDEO SYNC SIGNAL, AND REVERSE SPECTRAL SPREAD IS PERFORMED USING THIS PN INVERSE CODE. FIGURE 1