IEEE Trans Image Process. 2018 Feb;27(2):938-948. doi: 10.1109/TIP.2017.2771449. Epub 2017 Nov 9.
Enhancement of non-uniformly illuminated images often suffers from over-enhancement and produces unnatural results. This paper presents a naturalness preserved enhancement method for non-uniformly illuminated images, using multi-layer lightness statistics acquired from high-quality images. Our work makes three important contributions: designing a novel multi-layer image enhancement model; deriving the multi-layer lightness statistics of high-quality outdoor images, which are incorporated into the multi-layer enhancement model; and showing that the overall quality rating of enhanced images is consistent with a combination of contrast enhancement and naturalness preservation. Two separate human observer evaluation studies were conducted on naturalness preservation and overall image quality. The results showed the proposed method outperformed four compared state-of-the-art enhancement methods.
增强非均匀光照图像通常会遭受过增强，并产生不自然的结果。本文提出了一种使用从高质量图像中获取的多层亮度统计信息来增强非均匀光照图像的自然度的方法。我们的工作有三个重要贡献：设计了一种新颖的多层图像增强模型；推导了高质量户外图像的多层亮度统计信息，并将其纳入多层增强模型；并表明增强图像的整体质量评分与对比度增强和自然度保持的组合一致。我们进行了两项关于自然度保持和整体图像质量的独立人类观察者评估研究。结果表明，所提出的方法优于四种比较先进的增强方法。
