METHOD AND SYSTEM FOR SUPERIMPOSING AND TRANSMITTING ADDITIONAL INFORMATION, DEVICE FOR SUPERIMPOSING AND DETECTING ADDITIONAL INFORMATION AND STORAGE MEDIUM

摘要

PROBLEM TO BE SOLVED: To exactly and speedily detect additional information by detecting the N-fold unit block of one field in a video signal of the additional information with the synchronizing signal of the video signal as a reference and detecting the prescribed inverted unit block based on the detected result. SOLUTION: An analog signal S3 is supplied from a D/A converter 13 to a synchronizing separator part 18 and vertical and horizontal synchronizing signals are separated from the video signal, extracted and supplied to a timing signal generating part 19. While defining the N (N>=1) blocks of one field as a unit block, the inversion timing signal generating part of the timing signal generating part 19 generates an inversion timing signal HT for inverting the phase of a spreading code stream in the prescribed unit block for the unit of this unit block. The generated signal such as HT is supplied to an SS signal generating part 16. A spread spectrum signal S5 provided from the SS signal generating part 16 is supplied to a D/A converter 17, converted into an analog SS signal S6 and supplied to a superimposing part 14 and an analog video signal S7 is outputted.