Extraction and Visualization of A Class of Crack Defect

For crack defect,images are preprocessed using the method of morphological denoising.As crack always connects background in micro-computed tomography images,after region growing,edge extraction,elimination of speckle noise,morphological dilation and erosion,the exterior outline is closed,boundary is founded between region of crack and region of background.Operation of image subtraction is used to extract two dimensional feature of crack,and two dimensional cracks are visualized.