Make something white turn black

Hi, I have something to fix that should be pretty simple and I want to know what's the easiest and best way to do it. There's a shot with a character in darkness, wearing black, so everything is black besides her face. We see the tip of her white sleeve peaking through her black costume and it catches the eye and is distracting. She moves a bit in the shot. I think what I'm looking for is something that would turn white things black in a specific area, without turning the blacks white. Is there a tool for that? Or is there another way to do what I want to do? Thanks for your help!

You will have to mask out the white and then do a local color correction on it. In its most basic form that would be a brightness/contrast tool with the gain pulled back all the way to zero. But then you'll probably see black blobs, since hardly anything is black black. But apart from that: a luma key is probably the way to go, but you still have to do some additional masking to exclude the character's face.

Hey

You may :
1/ track the white tip (depending on the moves) or manually adjust a polygon on it
2/ add a timestretcher with a polygon spotted on a near black part of her sleeve. This polygon is supposed to cover the white part
3/ merge the black part on the white part and make it follow the moves (with a matchmove mode if you tracked it in step 1)

In other words, you extend the costume over the white sleeve, sort of mimicking what the patch replacer would do in Resolve.
BTW note that you may do more or less the same with a Paint node

Another option, depending on how big the offending sleeve is, is to use an ErodeDilate to erode away the white. It'll pull surrounding darker colors, removing the white. Then you do it again in the opposite direction to partially restore the original shapes. Usually you'll need to then regrain and maybe sharpen so the treated spot isn't obvious. This is the same process as a blemish removal; it only works for very small areas.

Thanks everyone!

[off-topic, sorry]

Hey Bryan, what's up ? Still torturing Houdini ?

[off-topic, thank you]

I think I would do it as I'm used to in Photoshop. Make a whole image adjustment and than mask out the area using either polyline, B-Spline or PaintMask tools + tracking of course.

I would either use Color Correct tool - Histogram - Equalize to equalize the brightness values in a relatively pleasing way. Make sure you are in Linear - 16 or 32 bit float mode for this. And than use say, Range or Bitmap mask tool to limit the effect to specific luminance values.

[off-topic, sorry]

Hey Bryan, what's up ? Still torturing Houdini ?

[off-topic, thank you]

Ayup. I'm paying some extra attention to Fusion this week 'cause NAB and very pleased to see continuing advancements in the USD implementation. I need to find some time soon to play with the Solaris -> Fusion pipeline again, see how our new MtlX catalog materials look.