Image signal transmitting method, superimposed signal extracting method, image signal output and receiving apparatus, and image signal recording medium

Abstract

The PN code generation controlling means 15 produces a PN code generation clock signal PNCLK to generate the PN code of one chip to one vertical section and supplies this clock signal to an SS duplication preventing control signal generating means 16. The SS duplication preventing control signal generating means 16 generates the PN code of one chip to one vertical section depending on the PN code generation clock signal PNCLK and executes the spectrum spread to the duplication preventing control signal S3 using this PN code to form the SS duplication preventing control signal S5. The SS duplication preventing control signal S5 is superimposed to the image signal and is then output. Thereby, elimination and deterioration of the additional information which has been spectrum spread and is then superimposed into the image signal can be prevented to surely provide the additional information superimposed to the image signal.

Description

technical field [0001] The present invention relates to a method and device for reversely duplicating information according to extracted additional information, by outputting an image signal superimposed with additional information and then receiving the image signal to extract the superimposed additional information, the present invention also relates to a An image signal recording medium, for example, is a case where an image signal recorded on the recording medium is reproduced and then transmitted together with an anti-duplication signal, and the transmitted image signal is received to restrict or prohibit or other recording media. Background technique [0002] VTRs (Video Tape Recorders) have been widely used in daily life, and various software capable of playback on the VTRs are widely provided. Digital VTR or DVD (Digital Video Disc) playback devices are also now available, providing extremely high picture and sound quality. [0003] On the other hand, however, the ...

AI Technical Summary

Problems solved by technology

[0037] As described above, when the spectrum spread duplication prevention control signal is damaged due to the following reasons, that is, the image formed by the image signal superimposed with the spectrum spread duplication prevention control signal is enlarged, or compressed, or the system conversion of the image signal is performed , or playback at various speeds, or cut editing, since the original copy prevention control signal cannot be extracted, copy prevention control in accordance with the copy prevention control signal cannot be performed

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