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Image Segmentation based on multicue fusion. XiaoweiGeng 2007.09.24. Content. Introduction about image segmentation image segmentation priciples Main Process Related Results. Main Principles. Conditional Random Fields Model Mean Shift For color likelihood estimation
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Image Segmentation based on multicue fusion XiaoweiGeng 2007.09.24
Content • Introduction about image segmentation • image segmentation priciples • Main Process • Related Results
Main Principles • Conditional Random Fields Model • Mean Shift For color likelihood estimation • Gabor Filters For texture likelihood estimation • Energy Optimized by Graph Cuts
Conditional Random Fields • Definition (1) G=(V,E) is a graph (2) Y is indexed by the vertices of G . (3) the random variables obey the Markov property with respect to the graph, when conditioned on X : (X,Y) is a conditional random field. where means that w and v are neighbors in G.
Conditional Random Fields • Characteristics where x is data information,y is label information,and y|s is the set of components of y associated with the vertices in subgraph S.
Kernel Density Estimation (1) Kernel density estimator (2) two methods of H chosen in practice
Mean Shift • A method to find modes of function
Gabor Filters • Biological enlightenment • The Gabor Filters characteristics
Image Segmentation based on CRF • Construct Energy Function
Energy Function • Our Energy Function As the similar presentation of MRF,we still use the classification to explain every term.
Color Likelihood Term • Similar to Bayesian explanation,we define Here ,xi is the mean value of background or foreground sample
Texture Likelihood Term • First , get the feature image by Gabor filters • second, use mean shift to filter the interesting regions to get the mean feature vector • Third ,use kernel density estimation to get the texture likelihood term
Smooth Term • Smooth Term in order to make the results more smooth,we define the color smooth and texture smooth Terms as:
Energy Optimize • Graph Cuts