'''Active shape models''' ('''ASMs)''') are [[statistical model]]s of the [[shape]] of objects which iteratively deform to fit to an example of the object in a new image, developed by Tim Cootes and Chris Taylor in 1995.<ref name=Cootes>{{cite journal| author=T.F. Cootes and C.J. Taylor and D.H. Cooper and J. Graham| title=Active shape models - their training and application| journal=Computer Vision and Image Understanding| pages=38–59| year=1995| issue=61}} [http://www.cs.ualberta.ca/~nray1/CMPUT615/Snake/cootes_cviu95.pdf]</ref> The shapes are constrained by the PDM ([[point distribution model]]) [[Statistical Shape Model]] to vary only in ways seen in a training set of labelled examples.
The shape of an object is represented by a set of points (controlled by the shape model). The ASM algorithm aims to match the model to a new image.
Line 10:
The technique has been widely used to analyse images of faces, mechanical assemblies and medical images (in 2D and 3D).
It is closely related to the [[active appearance model]]. It is also known as a “Smart"Smart Snakes”Snakes"<ref name=Cootes/> method, since it is an analog to an [[active contour model]] which would respect explicit shape constraints.
