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View Full Version : Courseware DVD:the 4:1:1 issue

ramiro
11-03-2004, 04:22 PM
There is an excellent chapter in the courseware dvd about keying dv footage. the example uses bluescreen footage and works well, but my problem is that i have footage shot on greenscreen with severe edge problems. since i dont understand exactly how channel booleans work, i dont know what needs to be changed so its applicable in greenscreen.
thanks
Jayk2k
11-03-2004, 08:25 PM
Use the exact same process... what hapens is the footage is converted from RGB (film and computer color space) to YUV (tv color space) and interpolated, and then converted back to RGB...

It should help your DV issues whether shot on red, green, or blue screen.
ramiro
11-04-2004, 12:57 PM
somehow it didnt work for me, ill check whether i did something wrong and get back to you.

by the way, i understand the colour space tool, what its for etc, but not the channel booleans, what you can do with it in general. would you mind explaining a few things?
thanks
Jayk2k
11-04-2004, 06:59 PM
Channnel Booleans is just that. It will let you apply all kinds of boolean or mathmatical operations between channels on 1 or 2 inputs. So if for example you had a horrible bluescreen, it is possible to subtract the red or green from it to yeild a better key.

You can also multiply, divide, min/max, etc. Quite powerfull once you experiment.
ramiro
11-05-2004, 11:45 AM
jason thanks for the replies on both messages, ill play around with channel booleans, it looks quite powerful.
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