Simply change them to monochrom with a tool like Paintshop Pro, then you've got your map.

Every color value from (0,0,0) to (255,255,255) is one height, so you have got the 2d-positions and the height and then simply render.

CU

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Skullpture Entertainment
#40842461

Does anyone know an algorithm for converting 2d pictures or photos to an array of height values. For example, converting an aerial photo to a voxel heightmap.

--Lee Mazurek--

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http://mazurek.dhs.org/3d/

That doesn't work at all for aerial photos. Now, the algorithm I'd use if I had to do something like that would be something like this:
It helps if you know where and how high the sun is. You'll need to find out where there are shadows (I don't know how) and then find the objects creating the shadows somehow, meanwhile working back the Lamberth formula for lighting and hoping that it works somewhat. Of course, even this way you'll only get relative heights. In other words, if you can get something with real height data, get it :P