zSurf4 is a utility that allows you to import a bitmap and export a surface.
You can find a copy at http://mwt.net/~sjedging/ZSURF4.zip
There is spotty info out there about this program, but its rather nice if you can figure out how to use it. The best tutorial I found is unfortunately not in English, however google translate helps with that.
The tutorial will give you a working knowledge Zsurf, at least enough to get started. I would like to add a method to start with a photograph of an object like a gear and end in a 3D surface. Note that the original is a pretty poor quality black and white image.
Zsurf likes very high contrast images. The image below if processed as is produces a very rough, jagged surface, raising all the dark spots and lowering all the white.
Here is the starting image, its a clock escapement wheel, its a jpeg image, of an actual photograph of a real escapement wheel.
