Contour to Hightmap - or RAW for Unity3D

Hi

Is it possible to convert terrain to a  height map with greyscale-encoded height values? Or RAW file?

My goal is to convert a Openroads terrain to RAW and import ti into Unity3D. If it is possible to export a heightmap, i could take it through L3DT and to a RAW and import into Unity3D

regards

Sigfús