True ortho

An orthophotomap is a raster image of the terrain surface created as a result of processing aerial or satellite imagery in order to obtain an image in an orthogonal projection, i.e. in a projection in which a standard map is presented. So far, orthophotomaps created in Poland correctly presented objects only at the ground level. The taller buildings were clearly tilted, obscuring some of the terrain content.

A true ortho, unlike "standard" ortho, solves this problem utilising the lack of radial shifts in the form of tilted buildings or "dead fields" understood as areas obscured by, for example, tall buildings.

The data set is available as Open Data.