Height Maps

I remember reading somewhere about height maps for WC3 and how to put them in maps, but I don't remember where. Basically I'm looking for how to do so.

EDIT: While searching through the tools at hive workshop I've found the solution, so no need to answer my question anymore. The tool is called Terrain 1.0 and it converts TGA to wc3 height map(w3e) so it can be imported into maps.