Lower brighter colors

[scrtagt69]

What filter could i use to lower brighter colors, specifically reds and oranges which are really bright?

[Mug Funky]

with a bit of brain-bending maths you could use masktools' YV12lut.

i'll come up with a nice expression for it in a moment.

[edit]

here it is...

change the "200" to whatever threshold you want, and change the "2" to whatever scale you want. at the moment it'll soft limit the red end of the chroma plane after the threshold.


yv12lut(vexpr="x 200 < x x 200 - 2 / 200 + ?",Y=2,U=2,V=3)


hope this is good enough. i only tested it on colourbars.

[edit edit]

simplified it and made it a little faster...

hmmm... the current settings are a little conservative. you could also try this for a stronger limit:
yv12lut(vexpr="x 192 < x x 192 - 4 / 192 + ?",Y=2,U=2,V=3)

don't ask why i always use mod16 numbers... force of habit i guess.

[scrtagt69]

thanks mug, i will try this later tonight when i get home. :)

[trevlac]

I made a plugin to do just this ...

http://forum.doom9.org/showthread.php?s=&threadid=74334&highlight=tweak+color

You can also use a vectorscope to see the difference/effects of the 2 methods. I'd use a gradation for such a test. I also wrote a vectorscope plugin (vdub actually but you can call if from avs), to test / see how to fix things like this. Search for vectorscope. :)