Anglia Ruskin Research Online (ARRO)
Browse

Automatic Detection of Hard Exudates in Color Retinal Images Using Dynamic Threshold and SVM Classification: Algorithm Development and Evaluation

Download (6.29 MB)
journal contribution
posted on 2023-07-26, 14:33 authored by Shengchun Long, Xiaoxiao Huang, Zhiqing Chen, Shahina Pardhan, Dingchang Zheng
Diabetic retinopathy (DR) is one of the most common causes of visual impairment. Automatic detection of hard exudates (HE) from retinal photographs is an important step for detection of DR. However, most of existing algorithms for HE detection are complex and inefficient. We have developed and evaluated an automatic retinal image processing algorithm for HE detection using dynamic threshold and fuzzy C-means clustering (FCM) followed by support vector machine (SVM) for classification. The proposed algorithm consisted of four main stages: (i) imaging preprocessing; (ii) localization of optic disc (OD); (iii) determination of candidate HE using dynamic threshold in combination with global threshold based on FCM; and (iv) extraction of eight texture features from the candidate HE region, which were then fed into an SVM classifier for automatic HE classification. The proposed algorithm was trained and cross-validated (10 fold) on a publicly available e-ophtha EX database (47 images) on pixel-level, achieving the overall average sensitivity, PPV, and F-score of 76.5%, 82.7%, and 76.7%. It was tested on another independent DIARETDB1 database (89 images) with the overall average sensitivity, specificity, and accuracy of 97.5%, 97.8%, and 97.7%, respectively. In summary, the satisfactory evaluation results on both retinal imaging databases demonstrated the effectiveness of our proposed algorithm for automatic HE detection, by using dynamic threshold and FCM followed by an SVM for classification.

History

Refereed

  • Yes

Volume

2019

Page range

3926930

Publication title

BioMed Research International

ISSN

2314-6141

Publisher

Hindawi

File version

  • Published version

Language

  • eng

Legacy posted date

2019-01-25

Legacy creation date

2019-01-25

Legacy Faculty/School/Department

Faculty of Health, Education, Medicine & Social Care

Usage metrics

    ARU Outputs

    Categories

    No categories selected

    Keywords

    Licence

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC