In general, as people age the functions of their sensory organs deteriorate. For example, in the eye of an elderly person, the visual field becomes dark owing to a decrease in the amount of light reaching the retina. Moreover, objects appear blurred due to a decrease in contrast sensitivity. In particular, the contrast sensitivity decreases remarkably as the spatial frequency increases. In this study, we propose an image enhancement method that considers the visual characteristics of elderly persons. The proposed method combines lightness correction and amplification of high spatial frequency components to obtain images with optimized visibility for elderly persons. In particular, lightness enhancement that guarantees color gamut via tone mapping is conducted. In addition, image sharpening is applied based on the inverse characteristic function of the contrast sensitivity curve. The experiments were performed using several digital color images to confirm the effectiveness of the proposed method.

中文翻译：

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基于老年人视觉特性的亮度校正和图像锐化增强图像

通常，随着人们年龄的增长，其感觉器官的功能也会恶化。例如，在老年人的眼睛中，由于到达视网膜的光量减少，视野变暗。此外，由于对比度灵敏度的降低，物体显得模糊。特别地，对比度灵敏度随着空间频率的增加而显着降低。在这项研究中，我们提出一种考虑老年人视觉特征的图像增强方法。所提出的方法结合了亮度校正和高空间频率分量的放大，以获得对老年人具有最佳可视性的图像。特别地，进行了通过色调映射保证色域的亮度增强。此外，基于对比敏感度曲线的逆特征函数应用图像锐化。使用几个数字彩色图像进行了实验，以确认所提出方法的有效性。