I was assuming it was semi transparent (they generally are here in aust) if it wasnt then some sort of PIC based "Blacker" would be achievablle ----- Original Message ----- From: "Picdude" To: Sent: Friday, June 20, 2003 6:54 PM Subject: Re: [OT]: TV question > On Friday 20 June 2003 03:20, Jake Anderson scribbled: > > ... > > would be hella difficult. > > ... > > Oh boy. Someone's watching a bit too much South Park. :-) > > > > ... Basically you would have to somehow reccord their > > logo against a black (0,0,0) and white (255,255,255) picture at the full TV > > scan speed. (difficult thing 1) then intercept the tv signal (presumabally > > after the tuner) and then subtract that image (with presumabally some > > brightness modifier) from the image passing through (difficult thing 2). > > the > > requirements for that in terms of AD and DA circutry are well fairly insane > > unless you happen to be phillips or something. > > Though I know if there were some sort of "black box" that could do it > > cheaply I would buy one ;-> > > As little as I know about TV signals, I would think it's a bit easier. I > don't see why record against black and white backgrounds. Capturing the logo > data should not be a problem -- snapshot the screen, import into graphics > app, outline the logo and fill with a certain color. Send it back to the > controller to capture as the mask. > > Assuming that they have totally blocked out the original image behind their > logo (ie: their logo is not semi-transparent), then you're not getting the > original picture back, so you're aiming for a black or grey replacement for > their logo, which will appear as a silhouette of their logo. But it will > serve the original purpose of not burning out that part of the screen. As an > alternative, consider boxing out that area, or if you've got more time on > your hands then consider fading the surrounding image into that logo spot. > If the logo is in a fixed spot, then it's in a fixed position within each > frame and that means at a certain time after the start of each frame. All > the controller would need to do is count time from the start of each frame > and at the appropriate moments, pass the signal for a black "pixel" instead > of the original frame. > > Cheers, > -Neil. > > -- > http://www.piclist.com hint: To leave the PICList > mailto:piclist-unsubscribe-request@mitvma.mit.edu -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu