COPYRIGHT PROTECTION METHOD AND DEVICE FOR HIGHLY PRECISE VIDEO SIGNAL, BROADCAST SYSTEM, RECEIVING DEVICE, RECORDING AND REPRODUCING METHOD AND DEVICE, AND REPRODUCING METHOD AND DEVICE

摘要

PROBLEM TO BE SOLVED: To surely protect the copyright by superimposing the information which is generated from the attendant information added to the highly precise video signals for protection of the copyright on the converted video signals as the electronic watermark information. SOLUTION: At the WM addition parts 106, 110 and 114, the duplication control signals are generated from the CGMS-D information which is decoded at a copy generation management system(CGMS) decoding part 105 and under the control of a control part 120. The PN codes which are used as the diffusion codes are generated in a sufficiently early cycle and multiplied by the duplication control information serving as the additional information to perform the spread spectrum and to convert the duplication control information of a narrow band and a high level into the signals of a wide band and a minute level which never affect the video signals. Then the duplication control information undergone the spread spectrum are superimposed on the video signals and transmitted.