DIGITAL INFORMATION INPUT OUTPUT DEVICE, RECEIVING DEVICE, RECORDING DEVICE, AND REPRODUCING DEVICE

摘要

PROBLEM TO BE SOLVED: To prevent wiretap and falsification of a program and to protect the copyright on a digital bus interface, when a digital broadcasting receiver and a digital VTR are connected and exchange of compressed video and a voice signal of a program or the like is performed through a digital interface. SOLUTION: An inputted digital signal is supplied to a ciphering circuit 303 and a changeover switch 305. The copy-limiting information of a digital signal inputted from an input terminal 301 is inputted to an input terminal 302. A copy-limiting information discriminating circuit 304 performs discrimination processing based on copy-limiting information inputted from the input terminal 302, operates the ciphering circuit 303, and switches the changeover switch 305. That is, since the inputted digital signal is ciphered by copy-limiting information and outputted, wiretap and falsification can be prevented and the copyright of a program can be protected.