Generating polygons/building footprints

[DebHollon]

Someone came to me and said "I saw someone do this; figure out how it works."  So now I am trying to figure it out.......

An aerial image of some sort (don't know the file type) was used as the reference layer.  A polygon footprint was drawn around each of a couple of the buildings.  A button was clicked and the remainder of the building footprints were generated.  It could be that it was just an image classification of a very large-scale image, but I don't know.  Does anyone know of another method that might generate a building footprint like that?

Thanks in advance.

[TimothyHales]

Yes, this sounds like some type of Image Classification.  It may be Feature Analyst which is an automated feature extraction extension  that enables GIS analyst to rapidly and accurately collect vector  feature data from high-resolution satellite and aerial imagery.  And there is also the ENVI Feature Extraction Module.

[DebHollon]

Thanks, Tim.  I'll try Feature Analyst to see how that looks.