Vision and Eye Research Unit, School of Medicine, Anglia Ruskin University, Cambridge, UK.
Sci Rep. 2019 Feb 4;9(1):1339. doi: 10.1038/s41598-018-37925-5.
Despite the significant advantages that smartphones' cameras can provide in teleophthalmology and artificial intelligence applications, their use as black-box systems for clinical data acquisition, without adequate information of the quality of photographs can compromise data accuracy. The aim of this study is to compare the objective and subjective quantification of conjunctival redness in images obtained with calibrated and non-calibrated cameras, in different lighting conditions and optical magnifications. One hundred ninety-two pictures of the eye were taken in 4 subjects using 3 smartphone cameras{Bq, Iphone, Nexus}, 2 lighting levels{high 815 lx, low 122 lx} and 2 magnification levels{high 10x, low 6x}. Images were duplicated: one set was white balanced and color corrected (calibrated) and the other was left as it was. Each image was subjective and objectively evaluated. There were no significant differences in subjective evaluation in any of the conditions whereas many statistically significant main effects and interaction effects were shown for all the objective metrics. The clinician's evaluation was not affected by different cameras, lighting conditions or optical magnifications, demonstrating the effectiveness of the human eye's color constancy properties. However, calibration of a smartphone's camera is essential when extracting objective data from images.
尽管智能手机的摄像头在远程眼科和人工智能应用中具有显著的优势，但如果没有对照片质量的充分了解，将其用作临床数据采集的黑盒系统可能会影响数据的准确性。本研究旨在比较在不同光照条件和光学放大倍数下，使用校准和非校准摄像头获取的结膜充血图像的客观和主观定量评估。使用 3 款智能手机摄像头{Bq、Iphone、Nexus}，在 4 名受试者的眼睛上拍摄了 192 张照片，2 种光照水平{高 815 lx，低 122 lx}和 2 种放大倍数{高 10x，低 6x}。图像被复制：一组进行了白平衡和颜色校正（校准），另一组则保持原样。对每张图像进行了主观和客观评估。在任何条件下，主观评估均无显著差异，而所有客观指标均显示出许多具有统计学意义的主效应和交互效应。临床医生的评估不受不同摄像头、光照条件或光学放大倍数的影响，这证明了人眼颜色恒常性的有效性。然而，当从图像中提取客观数据时，智能手机摄像头的校准是必不可少的。
