基于引导图像滤波器的水下图像清晰化算法  

Enhancing algorithm based on underwater optical imaging model and guided image filters

作　　者：陆慧敏[1,2,3] 胡学龙[4] 李玉洁[3] 李建如[1] 中岛翔太 芹川聖一 

机构地区：[1]同济大学海洋地质国家重点实验室,上海200092 [2]上海交通大学海洋工程国家实验室,上海200240 [3]九州工业大学工学研究院,福冈北九州8048550 [4]扬州大学信息工程学院,江苏扬州225127 [5]山口大学工学研究院,山口宇部7558611

出　　处：《扬州大学学报（自然科学版）》2015年第3期60-63,69,共5页Journal of Yangzhou University：Natural Science Edition

基　　金：日本学术振兴会特别研究基金资助项目(25J10713,15F15077);同济大学海洋地质国家重点实验室开放课题(MGK1407);上海交通大学海洋工程国家实验室开放课题(SKL1301);中国科学院海洋研究所开放课题(MGE2015KG02)

摘　　要：水下图像降质主要受水体中光的前后向散射、光波衰减、水中浮游生物以及水下光照不均匀等的影响.针对传统的水下图像采集器所获取的水下图像存在光照不均匀、纹理细节模糊及对比度低等问题,建立了一种新的水下图像光学成像模型,并提出一种基于引导图像滤波器的水下图像增强算法.根据水下光线的传播特性,充分利用双边图像滤波器的平滑保边特性以估计散射光和图像局域对比度,同时考虑不同波长在水下传输的特性,得到更加准确的水下图像增强模型,然后依据此模型复原清晰图像,并对复原图像进行校正处理.结果表明,该算法能克服光照不均匀等困难,对水下图像进行实时处理,有效地提高了图像的清晰度,且该方法已成功应用于深海观测系统.This paper describes a novel method to enhance underwater images by enhancing.Scattering and color change are two major problems of distortion for underwater imaging.Scattering is caused by large suspended particles,like fog or turbid water.Color change corresponds to the varying degrees of attenuation encountered by light traveling in the water with different wavelengths,rendering ambient underwater environments dominated by a bluish tone.Our key contribution is to compensate the attenuation discrepancy along the propagation path,and to take the influence of the possible presence of an artificial lighting source into consideration.Next,the water depth in the image scene is estimated.A simple colorization method is also utilized for restoring color balance.The enhanced images are characterized by reduced noised level,better exposedness of the dark regions,improved global contrast while the finest details and edges are enhance significantly.

关 键 词：水下图像 引导图像滤波器 图像复原 图像增强 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术]