Grayscale image segmentation by spatially variant mixture model with student's t-distribution

A spatially variant finite mixture model with Student's t-distribution component function is proposed for grayscale image segmentation. This model employs a new weight function which contains the information along the different spatial directions indicating the relationship of the pixels in the neighborhood. The label probability proportions are explicitly represented as probability vectors in the model. Gradient descend method is used to update the unknown parameters. The proposed model contains fewer parameters and it is easy to be implemented compare with the Markov random field (MRF) models. Comprehensive experiments on synthetic and natural images are carried out to demonstrate that the proposed model outperforms some other related ones.