Patent ID: 6058191
Filing Date: 2000-05-02
Classification: H04N

Abstract:
A method of removing in an RF domain the effects of copy protection signals added in blanking intervals of selected video lines of a video signal to prevent a recording of an acceptable copy of the video signal while allowing the copy protected video signal to be viewed, comprising the steps of:providing from the viewable video signal a sole RF carrier signal which contains the copy protection signals embedded therein in said selected video lines thereof;producing from the sole RF carrier signal a timing control signal indicative of the location of the copy protection signals; andmodifying in the RF domain, in response to the timing control signal, a quantity of the copy protection signals in the viewable video signal during their occurrence in the RF carrier signal such that the copy protection signals are sufficiently disabled when subsequently demodulated to allow the recording of an acceptable copy of the previously only viewable video signal.