>1) Use the sync detector to detect starts of frames and lines.
>2) Use a analog switch that will pass either the regular video or
>   pure white.
>3) Program the PIC to switch the switch at appropriate times.
>
>I've never done this, as I'm not a video guy, but I think the basic
>concept is sound.

I've done this.  One more point:

4)  Run the PIC synchronous to the horizontal clock rate.

Andy
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Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865 USA
              Electronics for Industry & R/C Hobbyists
         "Go fast, turn right, and keep the wet side down!"
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