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After segmenting candidate exudates regions in colour retinal images we present and compare two methods for their classification. The Neural Network based approach performs marginally better than the Support Vector Machine based approach, but we show that the latter are more flexible given criteria such as control of sensitivity and specificity rates. We(More)
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 morphology in colour space. We(More)
Many image-database retr-ieual systems rely heavily on the success oj one-shot queries, using optimised jemkre sets to obtain the best possible results. What is ojten missing jt-om this appToach is acceptance oj the fact that the user knows considerably more about the query being made than cm. be conveyed in szch Relatively simple terms. Ij the query jails(More)
Image segmentation is the first stage of processing in many practical computer vision systems. While development of particular segmentation algorithms has attracted considerable research interest, relatively little work has been published on the subject of their evaluation. In this paper we propose a framework for quantitative evaluation of segmentation(More)
This paper describes recent work on a neural network approach to outdoor scene interpretation. The results of evaluating a range of automatic region-based segmentation techniques based on a new segmentation quality metric are presented. The optimal technique is used to segment images of natural outdoor scenes. A powerful set of features designed for outdoor(More)
The problem of navigating a robot along a road is approached by means of creating and updating a simple representation of the road from a sequence of images. The representation chosen is a 4-parameter model that describes the width, direction and simple curvature of the road in a vehicle centred (X,Y,Z) world coordinate system. The model is created from(More)
This paper describes how the generation of 3-D models may b e a c hieved from a small number of images. It uses an automatic segmentation and a two stage iterative camera calibration and volumetric intersection algorithm to produce a set of 3D points in the form of a cloud of voxels. From this a polygonal or B-spline based surface representation of an(More)
Retinal exudates are typically manifested as spatially random yellow/white patches of varying sizes and shapes. They are a characteristic feature of retinal diseases such as diabetic maculopathy. An automatic method for the detection of exudate regions is introduced comprising image colour normalisation, enhancing the contrast between the objects and(More)