| 摘要 |
A spread code generation section (15) outputs selectively one of a plurality of different spectral spread codes (S6) corresponding to an anti-duplication control signal (S5) for indicating the content of the duplication prevention control such as duplication permission, duplication inhibition, and duplication of generation restriction of a video signal in a recording medium. The plurality of spectral spread codes is different in phase or series, or generated by multiplying a specified spread code by the plurality of different orthogonal codes. An additional information signal is spectrally spread using the selected spread code, and superimposed (13) on the video signal to output a combined information signal. The spectral spread code in the combined information signal is detected (23), duplication control of the video signal in the recording medium is performed (24) correspondingly to the detected spectral spread code, and the additional information is extracted by performing inversion spectral spread on the combined information signal using the detected spectral spread code. <IMAGE> |
