Gopalakrishnan, A.Almazroa, A.Raahemifar, K.Lakshminarayanan, V.2026-02-0620152015 2nd International Conference on Opto-Electronics and Applied Optics: Advances in Optical Sciences and Engineering II, IEM OPTRONIX 2015, 2015, Vol., , p. -https://doi.org/10.1109/OPTRONIX.2015.7345530https://idr.nitk.ac.in/handle/123456789/32276We present a technique to segment the optic disc (OD) boundary from a color retinal fundus image. The technique used involves the extraction and removal of blood vessels using a top hat transform and an inpainting process. Then, a circular Hough transform is applied to the detected edges to obtain a coarse boundary of the OD and following which probable points of the optic disc are fed to a curve fitting algorithm which uses a higher order polynomial to draw the final boundary of the optic disc. The optic disc segmentation is a crucial part in estimating the CDR (Cup-to-disc ratio) which can be used as an early indicator of glaucoma and for following the progression/remission of the disease. © 2015 IEEE.Curve fittingEdge DetectionGlaucomaImage SegmentationOptic DiscTop-Hat TransformOptic disc segmentation using circular hough transform and curve fitting