RGB Adjustment¶

Description

This filter is for simple manual color adjustment by RGB channel, either through adding constants, or changing the channel gammas or gains.

Parameters

Parameter	Value	Description
Action	Selection	Set the action to be performed[1]
Keep luma	Switch	Set to keep the luma value and the R/G/B sliders only affect the respective color channel
Alpha controlled	Switch	Check this if only areas with non-zero alpha are to be affected
Luma formula	Selection	Set the color space to operate in
R / G / B	Integer	Determines the change in each of the three color channels

The following selection items are available:

Action

Add constant	Adds a fixed value between -150 and +150 (this is sometimes called “black level” or “setup”).
	Simply shifts the RGB “cube” color space. This means, that on one end we are left with empty space, which is filled with zeros, and on the other end, values can “fall outside”, and in this case they will be truncated to max (255).
Change gamma	Changes channel gamma between 0.3333 and 3.0.
	Keeps the whole cube in the same place, just stretches and squeezes its interior, so no zero filling or truncation is necessary.
Multiply	Multiplies channel with a value between 0.3333 and 3.0 (sometimes called “gain” or “contrast”)
	Changes the size of the cube, keeping the “black” corner fixed, affecting predominately highlights, but the other end can still “fall out” and get 255 truncated.

Luma formula

Rec. 709	Default
Rec. 601