基于距离加权色偏估计的低质图像增强  

Low-Quality Image Enhancement Based on Distance Weighted Color Cast Estimation

作　　者：曹思颖 张弦[1] 蒲恬 彭真明 CAO Siying;ZHANG Xuan;PU Tian;PENG Zhenming(School of Information and Communication Engineering,University of Electronic Science and Technology of China,Chengdu 611731,China;Laboratory of Image Detection and Intelligent Perception,School of Information and Communication Engineering,University of Electronic Science and Technology of China,Chengdu 610054,China)

机构地区：[1]电子科技大学信息与通信工程学院,成都611731 [2]电子科技大学成像探测与智能感知实验室,成都610054

出　　处：《数据采集与处理》2023年第1期141-149,共9页Journal of Data Acquisition and Processing

基　　金：四川省自然科学基金(2022NSFSC0574);四川省科技计划(2022YFG0178);国家自然科学基金(61775030)。

摘　　要：有色雾、烟、尘等恶劣大气条件下的低质图像具有低可见度和颜色偏移的特点,给人类观察和计算机视觉应用带来困难。当前针对此类图像的增强算法通常忽略了景物与相机的距离对色偏的影响,为了在增强可见度时更好地恢复图像颜色,本文提出低质图像成像可见度下降及色偏与景物距离的关系模型和求解方法。该方法首先通过图像的局部亮度估算距离,然后通过距离估算图像的色偏矩阵,再求解退化模型得到可见度与颜色得到恢复的图像,最后将恢复的图像与限制对比度自适应直方图均衡(Contrast limited adaptive histogram equalization,CLAHE)增强图像进行距离加权融合,得到进一步细节增强的图像。实验表明,本文提出的方法与同类方法相比,在达到高图像质量评价指标的同时,明显具有更好的颜色恢复结果。Low-quality images under harsh atmospheric conditions such as colored fog,smoke and dust are characterized by low visibility and color cast,which bring difficulties to human observation and computer vision applications.Current enhancement algorithms for such images usually ignore the influence of the distance from the scene to the camera on the color cast.In order to better restore color while enhancing visibility,a relationship model between visibility reduction,color cast and distance and its solution method are proposed.First,the distance is estimated by the local brightness of the image,and the color cast matrix of the image is estimated by the distance.Then,the visibility and color restored image is obtained by solving the degradation model.Finally,the restored image is fused with a contrast limited adaptive histogram equalization(CLAHE)enhanced image by distance weighting for further detail enhancement.Experiments show that,compared with similar methods,the proposed method achieves high image quality evaluation indexes and has significantly better color recovery results.

关 键 词：图像复原 色偏校正 距离估计 色偏模型 低质图像 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置]