Parametric mask for Hue/Lightness/Saturation filter


#1

I would like to change the saturation and lightness of a specific color range (e.g. red tones) in my video. Currently I don’t see a way to do this in ShotCut (if I just don’t get it how to mask for a color range I would really appreciate if someone could point me into the right direction).

In case one cannot realize this feature in ShotCut, I would propose a parametric mask which applies the hue/lightness/saturation change only to a specific tonal range (minimum/maximum hue, saturation and/or luminance) with an optional blur to soften a bit the border line between the modified and the unmodified areas of the video.

Thanks a lot in advance,
Christoph


#2

Are you looking for something similar to the Hue vs Hue filter in Blender or DaVinci Resolve? Shotcut does not have that yet to my knowledge.


#3

Thanks for the answer. Unfortunately, I don’t have any experience with Blender. I’m more from a photographic background. Tools like Darktable have a parametric mask which limits the effect of a filter to only certain parts of an image https://www.darktable.org/usermanual/en/parametric_mask.html. Maybe something like this might also be useful for video processing.


#4

I see what you’re doing now. Hue vs Hue won’t get you there if you’re trying to do something extreme like selective monochrome. But an idea did just come to mind… what if you used a combination of chroma keying and color grading? A first-pass super-beta idea could be:

V2: copy of clip with chroma key on color you want to modify
V1: copy of clip with color grading to the new color you want

The chroma key on V2 would create a hole that can see down to the color-graded version on V1. Kinda hacky, and there’s probably a better way to do it, but it might work if you’re on a time crunch.


#5

Thanks a lot for your response! I’ll give that a try and see how it works.


#6

It is possible to use Chroma Key with the new Mask: Apply filter. Simply start first with a Mask: Simple Shape to initialize the masking process and set its width and height to 0. Then, add the Chroma Key to shape the alpha channel. You can use any filter affecting the alpha channel at this point. Next, add your level and color filters. Lastly, add Mask: Apply.


#7

I just gave it a try and it looks promising.

Thanks a lot for your support!