[Joris Corthout] "So if my composition of 30.000 pixels wide has: one white vertical line on pixel nr1 then 9 black lines, 1 white line, 9 black ones,... and then I compress it, I should get a nice white solid in the 3000 pixels wide compo"
It would be much easier to simply create a 3Kx3K white solid and then render that. ;-) haha, just kidding. Sorry I couldn't resist.
Like Kevin says, you need to provide more info. Your ideal solution will probably involve Scripting or Expressions. So more info will be good. Also, do post this in the COW's AE Expression Forum once you have more info.
Cheers
RoRK
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