GIMP Plugin Registry

Easily map colours from a source colour to a target colour. Very effective for matching skin tones across images or between people.

Relatively quick (but not earth shattering). It doesn't work with grayscale or indexed images. Has preview, works with selections and layers, etc. Very, easy to use, and quite useful for portraits or recolouring graphics.

A demonstration: Lenna's face is mapped to the colour of the feather on her hat. This was done by selecting a colour from her face, then selecting a colour from the feather.  read more »

It generates a ruler to embed into geographical maps. It allows to customize scale, colors and other things.

The main options are: Step(px) and Step(unit). They define the scale of the rule. Each "px" a step is drawn, representing "unit" kilometers, miles or meters, etc.

See the Screenshots

This plug-in changes colors in an image based on the HSV difference between two colors. This is particularly useful for applying color themes to existing images.
It avoids burning out high saturation and value at the expense of compression them somewhat when the difference goes towards higher saturation and value.
Current bugs/missing features include:
Undo does not work.
It can't be used on indexed images, even though it would frequently have enough colors.  read more »

Create large and natural textures from a small sample. Based on a 2003 research article. Can also create tileable textures. See homepage :
http://gimp-texturize.sourceforge.net/
Sometimes remembered as "texturizer", but the original name is Texturize.
Writtent by Manu Cornet (http://manucornet.net/) and Jean-Baptiste Rouquier (http://www.rouquier.org/jb).

Applies Gaussian blurs using different radii for different parts of the image, according to a map.  read more »