GIMP Plugins

Python compositing plugins for GIMP v01

I have written a number of GIMP plugins for personal use that might be useful to other people as well. These are basic implementations of several common compositing techniques. The package contains the following scripts:

  • Chroma Key - A basic chroma keyer that generates a layer mask based on the input color. It features two operating modes (RGB & HSI), an exponent setting for edge sharpness and support for a garbage mask.
  • Color Difference - A straightforward color difference keyer. It generates a layer mask based on the difference between the color channels. It supports all three RGB channels.
  • Despill - To remove color spill after keying. It generates two additional layers; one to subtract the spill color and one to control the brightness of the despilled areas.
  • Edge Wrap - Generates a layer that wraps the background over the edges of the foreground. It has settings for the blur sizes of the inner edge mask and the background.
  • Premultiply - Multiplies the RGB values with the alpha value creating a premultiplied image.
  • Split Contrast - Increases the contrast while minimizing the amount of banding and clipping. It generates two layers; one to control the brighter areas and one to control the darker areas. Settings are available to minimize clipping in very bright or very dark images and to prevent increasing the color saturation.

To install the plugins simply extract the contents of the package to the GIMP plugins directory. The plugins will be available from the Custom>Comp menu. If you are unsure about the location of the plugins directory you can find it in the Preferences dialog under Folders>Plug-Ins.


Rotoscoping for Blender 2.59

With the Blender 2.6 release this addon has become obsolete and is no longer under active development. It may still provide some useful information on Python scripting for Blender, vector rasterization, etc. which is why I will keep it available for the time being.

For several years I felt an important part was missing from the compositing side of Blender, namely, rotoscoping. So, a while back I decided to try and add it myself. The result is Roto2D. It allows the user to create and animate Bezier masks in the Image Editor of Blender and makes them instantly available in the Node Editor. If you are not familiar with rotoscoping, have a look at the video on the right to get an idea.

The current version, 0.48a, is a combination of a Python script and a custom Blender build containing a number of functions written in C. In future versions the Python script will be replaced by a new rotoscoping compositing node to increase both speed and usability.

Downloads for both Windows and Linux are available for testing. For more information, please visit the Roto2D development blog.