ARIA is software written in MATLAB for the analysis of blood vessels in retinal images, and based upon an algorithm that has been published in PLoS ONE (title: 'Fast Retinal Vessel Detection and Measurement Using Wavelets and Edge Location Refinement').
In addition to MATLAB source code, the download contains a manual explaining how to use the software. It also contains test code that measures the algorithm performance using publicly available databases of retinal images. These tests can be reused to help with the development of alternative approaches.
