Novel pre-processing of colour fundus images

A new pre-processing method for colour fundus images with novel contribution of the red channel is proposed. Based on a condition that is developed in this paper, this method utilises the intensity information from both red and green channels (of the same retinal image). The histogram matching is used to modify the histogram of the green channel image by using the histogram of the red channel image to obtain a new processed image having the advantages of both images. This method can be used to correct non-uniform illuminations in colour fundus images or as a pre-processing step in the automatic analysis of retinal images.