Boundary extraction in thermal images by edge map
Quming Zhou, Zhuojing Li, J.K. Aggarwal · 2004
Extracting object boundaries in thermal images is a challenging task because of the amorphous nature of the images and the lack of sharp boundaries. Classical edge-based segmentation methods have the drawback of not connecting edge segments to form a distinct and meaningful boundary. Many level set approaches, which can deal with changes of topology and the presence of corners, have been developed to extract object boundaries. Previous researchers have used image gradient, edge strength, area minimization and region intensity to define the speed function. Our approach uses edge direction and magnitude, called an edge map, as the main component of the speed function. The edge map points toward the nearest boundary; its magnitude represents the total gradient energy in the half plane. The experimental results are significantly superior to those obtained using edge magnitude alone.