| 摘要 |
PURPOSE: To provide a copy-preventing constitution which does not visually degrade the quality of video software by inserting leading and trailing code sequences to encode a signal before recording on a video tape. CONSTITUTION: Leading and trailing code sequences are inserted to a luminance part of a video signal. Leading and trailing code sequences are inserted to a part of a corresponding line of video information and are accurately separated by one field. When first and second field decoders 72 and 74 include information corresponding to each other, an encoded video signal EVS is interpreted as a signal indicating a copyrighted video software, and the recording function is inhibited for a certain time. When decoders 72 and 74 include different information, the video signal has not been encoded, and consequently, it is interpreted as a signal indicating video software free of copyright. |
