1. In a computer system having as input a spatial dataset of n dimensions, where n is greater than or equal to 1, said dataset being descriptive of topographically descriptive regions, a method for extracting features from said spatial dataset comprising: providing feature specific indices; partitioning the dataset into topographically-contiguous regions using said feature specific indices; thereafter on each region, calculating a set of features wherein the features are considered sufficiently descriptive of the region; thereupon grouping together in a group at least two regions sharing said set of features, said at least two regions being topographically contiguous; and thereafter assembling the associated features of the group in a structure for input to a classifier.