Comparisons of the LBF model and the proposed ERBLS model on segmenting synthetic and two real blood vessel images with intensity inhomogeneity. Column (a): initial contours. The initial contours in row (f) (i) and (l) are obtained by Otsu threshold. Column (b): final segmentation results using the LBF model. Column (c): final segmentation results using our proposed ERBLS model. Size=127×96, 111×110, 103×131.