automatic detection of the optic disc of the retina: a fast method

localizing the optic disc (od) in retinal fundus images is of critical importance, since it is very similar to hard exudates (found in pathology) in color and brightness. because of the importance of od localization in clinical applications, many techniques have been developed. in this paper, we present the results obtained from two methods, correlation and least square, to approximate the optic cup. these methods are simple and are not complex, while most of the od detection algorithms are. the methods were tested on two groups of data, (a total of 100 color fundus images) and were 98% successful in detection of the optic cup. an algorithm using the vessel mask of fundus images is proposed to be run after correlation to ensure that the localization of od in all images is successful. it was tested on 40 of the test images and had a 100% rate of success.