Optic disc detection by earth mover's distance template matching

• Author(s): Monteiro, Fernando C. ; Cadavez, Vasco
• Date: 2011
• Persistent ID: http://hdl.handle.net/10198/7113
• Origin: Biblioteca Digital do IPB
• Subject(s): Diabetic retinopathy; Earth Mover’s distance; Gabor wavelets; Optic disc detection; Retinal images
• Document Type: Article
• Language: English

Description

This paper presents a method for the detection of OD in the retina which takes advantage of the powerful preprocessing techniques such as the contrast enhancement, Gabor wavelet transform for vessel segmentation, mathematical morphology and Earth Mover’s distance (EMD) as the matching process. The OD detection algorithm is based on matching the expected directional pattern of the retinal blood vessels. Vessel segmentation method produces segmentations by classifying each image pixel as vessel or nonvessel, based on the pixel’s feature vector. Feature vectors are composed of the pixel’s intensity and 2D Gabor wavelet transform responses taken at multiple scales. A simple matched filter is proposed to roughly match the direction of the vessels at the OD vicinity using the EMD. The minimum distance provides an estimate of the OD center coordinates. The method’s performance is evaluated on publicly available DRIVE and STARE databases. On the DRIVE database the OD center was detected correctly in all of the 40 images (100%) and on the STARE database the OD was detected correctly in 76 out of the 81 images, even in rather difficult pathological situations.