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mt_lutxy
Hi,
I can't get started with this function...
mt_lutxy
mt_lutxy : clip clip1, clip clip2, string expr("x"), string yexpr("x"), string uexpr("x"), string vexpr("x")
It applies a two-parameters function defined by expr to all the pixels. The function is written is reverse polish notation.
If yexpr, uexpr or vexpr isn't defined, expr is used instead.
1) How pixels of the clip 2 are used for calculation ?
- expr("x")
I guess the other expressions applies to Y, U, V ?
mt_lutxy(o,g,"x x y - abs "+string(z)+" / 1 "+string(pow)+" / ^ "+string(z)+" * "+string(str)+
\ " * x y - 2 ^ x y - 2 ^ "+string(ldmp)+" + / * x y - x y - abs 0.001 + / * +",U=2,V=2)
Ok, i know what reverse polish notation is, but i'm unable to understand this. It would be nice to have at least 1 example somewhere, to start with, explaining how the function is working on a simple task....
x y looks like Cartesian coordinates...
what does x x y ?
* x y - 2 ^ x y - 2 where comes clip2 in calculation ... ?
reverse notation, why is the * before the x, y :
* x y - x y ?
TIA, L
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