Extending Active Shape Models to Incorporate a-priori Knowledge about Structural Variability

A new deformable shape model is defined with the following properties: (1) A-priori knowledge describes shapes not only by statistical variation of a fixed structure like active shape/appearance model but also by variability of structure using a production system. (2) Multi-resolution description of shape structures enable more constrained statistical variation of shape as the model evolves in fitting the data. (3) It enables comparison between different shapes as well as characterizing and reconstructing instances of the same shape. Experiments on simulated 2D shapes demonstrate the ability of the algorithm to find structures of different shapes and also to characterize the statistical variability between instances of the same shape.