| 摘要 |
The "color stripe" process is well known in the video field for preventing copying of video by analog video tape recorders, and operates by altering the phase of a portion of the video signal color burst. Here, a weakened version of the color stripe process is installed in a video signal by a digital media player which plays or stores conventional digital media, such as an optical disc (e.g., DVD or CD) player, a hard disc drive, a digital tape drive, or solid state memory. Thereby in an analog video signal output by such a digital media player the color burst phase alterations are reduced or attenuated so there is no copy prevention effect on a conventional downstream (receiving) analog video tape recorder. However the weakened color stripe process is still sufficient to be detectable by a suitable detector located in a downstream compliant device such as a video recorder, so the detected presence of the installed color stripe serves as an encoded indication of copy control or other content control for the video signal by the compliant device. |
