For a more up to date description, see http://jake.askeland.ws/ .

TASPA began as a demonstration of a transitional vertex thinning algorithm based on convex polygon fitting.

TASPA is limited to monochromatic pixel weights (either a pixel is 'passable' or 'impassible' and 'passable' pixels have a weight of 1) and undirected graphs (A to B is equivalent to B to A).