An efficient estimation method for intensity factor of illumination changes
For intensity correction under illumination changes in video sequence, one of the main problems lies in the lack of adaptive technique for the classification of stationary and non-stationary pixels in the images. In this paper, we propose an efficient estimation approach for intensity factor of illumination changes in order to perform intensity correction for dynamic sequence images. Firstly, the ratio image is obtained, where the probability density function computed on pixel values can be considered as a mixture Gaussian model. Then the process of the parameter estimations is performed based on Expectationmaximization (EM) algorithm. Under the assumption of Gaussian distribution for the values of stationary pixels, the intensity factor can be estimated by using pixels adjacent to the mean value of Gaussian distribution related to the stationary class. Finally, two experiments are carried out to verify the proposed method.
intensity correction parameter estimation illumination variations em algorithm