The aim of the present work is to automaticaly describe and analyze volume images of aluminium foam obtained using a Tomahawk CT-system implemented on a Phillips HOMX 161 micro focus X-ray systeme. The next image show one 2D slice in the volume image.
In order to analyze the image, we first need to reconstruct the structure of closed cells. During acquisition of the images, some border of cells disapeared due to the finess of the border, or noise in the signal. In order to rebuild the correct cell structure, we use a segmentation algorithm based on the watershed.
First, a distance map is computed showing distance to the border. From that map, we extract local maxima which are used as seeds for the watershed algorithm.
The next images (same images with two differents colormap) show the result of the watershed algorithm applied to the aluminium foam image. Each different color represents a different cell. However, some cells have been oversegmented.
|last update: 06.12.2012|