COPY GUARD GENERATOR

摘要

PROBLEM TO BE SOLVED: To attain simple configuration for a receiver side device. SOLUTION: A timing generating circuit 12 at a transmitter side generates a timing signal denoting an additional information transmission period of received image data. Furthermore, a copy guard signal generating circuit 13 generates a digital copy guard signal in a timing of the timing signal. A selector 14 selects the digital copy guard signal for the additional information transmission period and selects image data from an input terminal 11 in other timing and provides an output of the selected data. The additional information transmission period for the input image data includes a vertical blanking period when the copy guard signal is inserted and the transmitter side multiplexes the digital copy guard signal for the additional information transmission period, then the receiver side obtains the image signal on which the copy guard signal is multiplexed. No copy guard signal generating circuit is required for the receiver side and then the hardware scale is reduced.