This paper presents a novel approach to the fast localization and extraction of optic disc from fundus images of the human retina. Optic disc continues to be a major landmark for fundus image registration and is indispensible for the understanding of retinal fundus images. For the detection of optic disc, we first decompose the image into its bit planes. The lower order bit planes are found to carry important information of the location of optic disc. Then we find the exact location by means of mathematical morphology. The algorithm has been tested on a subset of MESSIDOR1 image database with various visual qualities. Robustness with respect to the changes of the parameters of the algorithm has been evaluated.

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Image processing Optic disc localization Bit plane decomposition Mathematical morphology