GIMP Plugin Registry

Shape from shading algorithms have been around for a while. Dr. Mark J. Carlotto describes a simplified version using basic trigonometry (Sculptor's Photoclinometry page in the Pacific-Sierra Research Image Shape from Shading section). In that section, Dr. Carlotto describes the Berthold Klaus Paul Horn algorithm for generating shape from shading, first described by Horn in 1989.

This plug-in generates a 3D image or movie from a greyscale source image based on the shading of the image, the sun azimuth, the camera angle (called phase angle), and the pixel size. Originally designed to be used with Mars Orbiter Camera (MOC) images, the user should be familiar with Mars Orbiter Camera ancillary parameters. The plug-in should work with any planetary data system or terrestrial image provided that the above parameters are available.

The results of this plug-in have been somewhat ground-truthed using an ISS image of the Giza pyramids. However, due to the inability to ascertain or enter albedo values for the surface in question, the results should be accepted with CAUTION.

The plug-in is very resource intensive, and requires maximal memory to function effectively on large (1000x1000) images. The author recommends a minimum of 512MB of system memory.