Expert
Get flash to fully experience Pearltrees
Image Pipes
GIMP 1.2 introduced a lot of new features that have been further improved in version 2.0, including the ability to use full color "pixmap brushes".
Image Pipes 2
A pixmap brush is an image, with both shape and color, that gets drawn with one of the paint tools. The pencil draws the pixmap with a single click.
Sketch Effect
High pass filtering means that we filter away the low frequencies of something, and let the high frequency bands pass.
So, we want to create a nice paintbrush image with GIMP. This tutorial can be a bit complex and I think it is better for a bit more advanced GIMPer. If you want to learn the basics, a good way to do so is to get one of the many GIMP books written.
Draw A Paint Brush
Photo to sketch
Straightforward Sobel edge detect ( Filters -> Edge-Detect -> Sobel ) of original (don't forget to save a copy of the original) The Sobel edge detect should be done on the background image (without an alpha channel) rather than a copy of the background (which has an alpha channel). Bring out detail with an auto-equalise ( Layer -> Colors -> Auto -> Auto-Equalize ) of the sobel edge detect, and convert it to greys using desaturate ( Layer -> Colors -> Desaturate ). We only want the strong edges, otherwise it'll look crap.
Almost every desktop enviroment I've seen has a special application for creating icons, usually a very limited drawing application. In this short tutorial, we'll show you how GIMP (GNU Image Manipulation Program) can help you create icons for your desktop. GIMP enables you to save compressed files and work with them transparently, using the .xcf format. However, since we're working with very small files, compression simply doesn't save enough space to justify the effort. Especially since filemanagers like Nautilus have problems with creating thumbnails for compressed images, it's best to accompany any .xcf files you produce with a .png version. (See Image above)
Creating Icons
GAP is an advanced tool to be able to create animations, this guide should give you some sort of view of how GAP works and what you can do with it.
Using GAP
