Divide a raster map by maeans of a polygon

Discussion created by guillem84 on Jan 25, 2011
Dear collegues,

I would like to know if it is possible to individualize a raster map by means of a polygon (feature). Like I show in the figure below, I have this raster map with diferent colours and I would like to separate according to the diferent polygons I have on it (black lines). My objective is to be able to work with each part of the raster individually. I have been thinking of vectorizing the raster map and then apply a "clip", "union" or intersect with the polygons but i would like to keep the raster format.

Best wishes,