Abstract
Nowadays, due to the developing the hardware of X-ray Computed Tomography (CT) scanner, it is available to visualize pore structure of geomaterials and to evaluate it quantitatively. The important issue is how to threshold CT-value on X-ray CT image. If the spatial distribution of density is unknown, it should be difficult to define the thresholding value of CT data in an objective way. The purpose of this study is to propose the image segmentation technique for X-ray CT image using Expectation Maximization (EM) algorithm. In this paper, the effectiveness of EM algorithm for histogram segmentation was evaluated and the amount of mixel and its spatial distribution were estimated.