Two-dimensional Correlation Based Image Segmentation and Its Fast Recursive Algorithm
Guan Xinping · Journal of the China Railway Society · 2007
A two-dimensional correlation image thresholding algorithm is proposed on the basis of the two-dimensional histogram.First,a smoothed image is obtained using the neighbor smoothing technique.The two-dimensional histogram is constructed using the gray value and average gray value of a pixel.The two-dimensional threshold is obtained according to the maximum correlation criterion.Compared to the one-dimensional case,the two-dimensional correlation thresholding method can get better segmentation results,because it considers not only image-pixel gray information but also spatial neighbor information.To reduce computation complexity,a fast recursive algorithm is presented.In the fast recursive algorithm,the computation of two-dimensional correlation is written in the recursive form.Many repeated calculations are avoided.The computation complexity is reduced from O(L4) to O(L2).The computation time is also reduced dramatically.This facilitates the recursive algorithm application in the real-time image processing system.