In the field of computer vision, principle component analysis (PCA) is
often used to provide statistical models of shape, deformation or app
earance. This simple statistical model provides a constrained. compact
approach to model based vision. However, as larger problems are consi
dered. high dimensionality and nonlinearity make linear PCA an unsuita
ble and unreliable approach. A nonlinear PCA (NLPCA) technique is prop
osed which uses cluster analysis and dimensional reduction to provide
a fast. robust solution. Simulation results on both 2D contour models
and greyscale images are presented.