Fig. 1.

Typical images and the corresponding manual labels from the DRIVE, INSPIRE, and REVEAL database. (a) and (f) are typical image and manual segmentation from the DRIVE data set. (b) and (g) are typical image and manual segmentation from the INSPIRE data set. It should be noted that the original manual segmentation only contains vessel centerlines of 1-pixel width, which is dilated for the sake of better visualization. (c)-(e) and (h)-(j) are typical images and manual segmentations from the REVEAL database. From left to right are images from REVEAL 1, 2, and 3, respectively.