A new approach toward target representation and localization, the central component in visual tracking of nonrigid objects, is proposed. The feature histogram-based target representations are regularized by spatial masking with an isotropic kernel.

基于matlab的4种梯度算子，Sobel Operator、Laplacian Operator、Prewitt Operator-Matlab based on the four kinds of gradient operator

matlab code is designed for template matching and further extraction of water bodies from satellite images based on gradient density. code also consists of color segmentation and automatic useful cluster selections.