Desaturate the color of an object or Group of objects. This sets the values of R, G, and B to the average of the maximum of R, G, and B; and the minimum of R, G, and B. For example, R would be set to (max( R, G, B ) + min( R, G, B ))/2.

Left: Original colors. Right: Colors after applying the Color Desaturate effect.

Brighten the color of an object or Group of objects. This effect has the property of making dark colors more intense but washing out light colors.

Left: Original colors. Right: Colors after applying the Color Brighter effect.

This effect allows color custom transformation functions to be defined. Standard math operations are allowed such as +, −, ×, and /. If a a resulting value is outside the allowed limits, it is set at the minimum or maximum allowed value.

Custom Color Effect dialog set to reduce R (red) to one half.

Left: Original colors. Right: Colors after applying the Color Custom effect with the specification that R should be divided by 2.

Darken the color of an object or Group of objects. Each R, G, and B component of a color is set to 90% of its previous value.

Left: Original colors. Right: Colors after applying the Color Darker effect.

Change the color to a gray using the formula for Luminance used by the NTSC and PAL television standards. This sets the color to a lightness (Y) defined by: Y = 0.229 × R + 0.587; × G + 0.114 × B. See the Wikipedia entry for YUV for further information.

Left: Original colors. Right: Colors after applying the Color Grayscale effect.

Decrease the hue (see the section called “HSL”) of a color. The hue is decreased by 5% (of the full hue range) or equivalently, a rotation of 18° around the color circle. This, for example, means that a pure red picks up a touch of blue in the RGB color space.

Left: Original colors. Right: Colors after applying the Color Less Hue effect.

Decrease the lightness (see the section called “HSL”) of a color. The lightness is decreased by 5% (of the full lightness range). If the lightness is already less than 5%, it is set to 0%.

Left: Original colors. Right: Colors after applying the Color Less Light effect.

Decrease the saturation (see the section called “HSL”) of a color. The saturation is decreased by 5% (of the full saturation range). If the saturation is already less than 5%, it is set to 0%.

Left: Original colors. Right: Colors after applying the Color Less Saturation effect.

Increase the hue (see the section called “HSL”) of a color. The hue is increased by 5% (of the full hue range) or equivalently, a rotation of 18 degrees, around the color circle. This, for example, means that a pure red picks up a touch of green in the RGB color space.

Left: Original colors. Right: Colors after applying the Color More Hue effect.

Increase the lightness (see the section called “HSL”) of a color. The lightness is increased by 5% (of the full lightness range). If the lightness is already more than 95%, it is set to 100%.

Left: Original colors. Right: Colors after applying the Color More Light effect.

Increase the saturation (see the section called “HSL”) of a color. The saturation is increased by 5% (of the full saturation range). If the saturation is already more than 95%, it is set to 100%.

Left: Original colors. Right: Colors after applying the Color More Saturation effect.

Invert the color. For example, an R value of 64 (25%) becomes an R value of 191 (255−64, or 75%).

Left: Original colors. Right: Colors after applying the Color Negative effect.

New in v0.46

Randomize the color of selected objects or all objects if no object is selected. One can choose which of the HSL color parameters to randomize (hue, saturation, and/or lightness).

A grid of gray squares after randomizing their colors. Left: Randomizing hue, saturation, and lightness. Right: Randomizing only lightness.

Set the B value in RGB to 0.

Left: Original colors. Right: Colors after applying the Color Remove Blue effect.

Set the R value in RGB to 0.

Left: Original colors. Right: Colors after applying the Color Remove Red effect.

Set the G value in RGB to 0.

Left: Original colors. Right: Colors after applying the Color Remove Green effect.

New in v0.46

Replace a color among selected objects or all objects if no object is selected. Color are specified in RRGGBB hexadecimal form. Color to be replaced must match exactly.