Automatic location of optic disk in retinal images

On the research work leading to automatic analysis of retinal fundus images the knowledge of optic disk location is very essential, and a new method to automatically locate optic disk is proposed in this paper. The candidate regions are first determined by clustering the brightest pixels in intensity image. Principal Component Analysis (PCA) is then applied to these candidate regions. The minimum distance between the original retinal image and its projection onto "disk space" is located as the center of optic disk. The algorithm has been tested and compared with another commonly used method and the results show that the method proposed here can automatically provide more acceptable location of the optic disk.