Fig. 4.

Vessel extraction with the two-scale Gabor filter algorithm. The results of the vessel extraction using the two-scale Gabor filter algorithm is shown here for the corresponding fundus images in Fig. 3. Green pixel highlight correctly segmented pixels (true positives), red pixels show those vessel pixels falsely segmented as background (false negatives), and in blue are the oversegmented, or false positive, pixels shown (when compared to the manually segmented vasculature, the ground truth). The scale bars (short white bar in the bottom left corner of each panel) correspond to 300 pixels.