Comparison of Colour Spaces for Optic Disc Localisation in Retinal Images

The location of the optic disc is of critical importance in retinal image analysis. In this work we improve on an approach introduced in [3] who localised an optic disc region through greylevel morphology followed by snake fitting. We propose and implement both the automatic initialisation of the snake and the application of morphol-ogy in colour space. We examine various methods of per-forming the morphology step (to remove the interference of blood vessels) and compare them against each other. We demonstrate that our proposed simple Lab colour morphology method is particularly suitable for the charac-teristics of our optic disc images. Results indicate 90.32% average accuracy in localising the optic disc boundary.