No-reference quality index for color retinal images
Abdel-Hamid L, El-Rafei A, Michelson G (2017)
Publication Type: Journal article
Publication year: 2017
Journal
Book Volume: 90
Pages Range: 68-75
DOI: 10.1016/j.compbiomed.2017.09.012
Abstract
Retinal image quality assessment (RIQA) is essential to assure that the images investigated by ophthalmologists or automatic systems are suitable for reliable medical diagnosis. Measure-based RIQA techniques have several advantages over the more commonly used binary classification-based RIQA methods. Numeric quality measures can aid ophthalmologists in associating a degree of confidence to the diagnosis performed through the investigation of a certain retinal image. Moreover, a numeric quality index can provide a mean for identifying the degree of enhancement required as well as to evaluate and compare the improvement achieved by enhancement techniques. In this work, a no-reference retinal image sharpness numeric quality index is introduced that is computed from the wavelet decomposition of the images. In order to account for the obscured retinal structures in unevenly illuminated image regions, the quality index is modified by a homogeneity parameter calculated from the previously introduced retinal image saturation channel. The proposed quality index was validated and tested on two datasets having different resolutions and quality grades. A strong (Spearman's coefficient > 0.8) and statistically highly significant (p-value < 0.001) correlation was found between the introduced quality index and the subjective human scores for the two different datasets. Moreover, multiclass classification using solely the devised retinal image quality index as a feature resulted in a micro average F-measure of 0.84 and 0.95 using the high and low resolution datasets, respectively. Several comparisons with other retinal image quality measures demonstrated superiority of the proposed quality index in both performance and speed.
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Egypt (EG)How to cite
APA:
Abdel-Hamid, L., El-Rafei, A., & Michelson, G. (2017). No-reference quality index for color retinal images. Computers in Biology and Medicine, 90, 68-75. https://doi.org/10.1016/j.compbiomed.2017.09.012
MLA:
Abdel-Hamid, Lamiaa, Ahmed El-Rafei, and Georg Michelson. "No-reference quality index for color retinal images." Computers in Biology and Medicine 90 (2017): 68-75.
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