This is a normal map generator from a single image, originally created by omaremad. Load a single layer picture, then choose filters/map/insanebump..., tweak the details, then hit OK. The normal/height/ambiend/specular maps for the picture will be created within the folder where the original picture resides.
The script produces different files within the original image's directory:
the _n is the normal map,
the _s is the specular,
the _d is the diffusion (just the color)
the _a is the ambiend occlusion
the _h is the displacement (or height map)