COMPUTER SYSTEM AND VIDEO REPRODUCING OUTPUT CONTROL METHOD

摘要

PROBLEM TO BE SOLVED: To provide a computer system which outputs copy protected video data on a monitor display by copy protecting without fail. SOLUTION: A decorder 11 decodes video data 10 to output decorded data and performs a decorder authentication whether or not the video data 10 is a piece of data reproduced by a normal reproducing route. A graphic controller 14 performs copy protect authentication whether or not the video data 10 is copy protected using a digital watermark information detected in video data. When both of the decorder authentication and the copy protection authentication work out, the decorded data are output on the monitor display 15 through a video memory 13 after copy protecting. When the decorder authentication fails and the copy protection authentication works out, output of the decorded data on the monitor display 15 is prohibited. COPYRIGHT: (C)2005,JPO&NCIPI