Extraction of Blood Vessels in Retinal Images Using Four Different Techniques

Figure 18

Application of Continuation Algorithm to a typical poor quality retinal image, (a) image obtained from the image in Figure 17(a) in the first pass of continuation algorithm, (b) image obtained in the second pass of continuation algorithm applied on the vertically flipped version of the image shown in (a), (c) image obtained in the third pass of continuation algorithm applied on the horizontally flipped version of the image shown in (b), (d) image obtained in the fourth pass of continuation algorithm applied on the vertically flipped image in (c) and shown after horizontal flip.