基于残差和高频替换的SONY-RGBW阵列彩色重构方法  

Residual and High-frequency Replacement Based Color Reconstruction Method for SONY-RGBW Array

作　　者：王海琳 韩正昊 李力 裘溯 金伟其 Wang Hailin;Han Zhenghao;Li Li;Qiu Su;Jin Weiqi(MoE Key Lab of Photoelectronic Imaging Technology and System,School of Optics and Photonics,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学光电学院光电成像技术与系统教育部重点实验室,北京100081

出　　处：《激光与光电子学进展》2021年第20期58-70,共13页Laser & Optoelectronics Progress

基　　金：陆装十三五预研基金项目(6140414050327);微光夜视技术重点实验室基金(J20170101)。

摘　　要：RGBW滤光阵列常被用于提升探测器在低照度下的成像质量,但相应的彩色重构方法依然是结合拜尔阵列特点设计的,未充分利用亮度信息的优势,故重构结果较差。针对这一缺陷,首先,使用引导滤波挖掘亮度信息和彩色信息的关联性。然后,根据残差的平滑性,设计了适用于SONY-RGBW滤光阵列空域特点的采样率逐步提升的多步残差插值算法。接着,为改进算法边缘适应性,结合在正交方向上的插值结果,引入迭代过程并改进逐像素的评价因子。最后,利用亮度信息的高频成分增强彩色图像。在Kodak数据集和实际场景采集图像上的实验结果表明,所提方法能够降低颜色混叠,重构出清晰的图像细节,且有/无参考图像的客观评价指标优于现有RGBW滤光阵列彩色重构方法。RGBW filter arrays are often used to improve the imaging quality of detectors at low illuminance,but the corresponding color reconstruction methods are still designed according to the characteristics of Bayer array,and do not make full use of the advantages of luminance information,resulting in poor reconstruction results.To overcome this defect,guided filtering is applied to delve the correlation between luminance information and color information first.Then,multi-step residual-based interpolation algorithm with increasing sampling rate is designed,based on the smoothness of residual,which is applied to the spatial characteristics of the SONY-RGBW color filter array.Moreover,combined with the interpolation results in the orthogonal directions,the iterative process is introduced and the pixel-wise evaluation factor is improved to improve the edge adaptability of the algorithm.Finally,the highfrequency component of the luminance image is used to enhance the color image.Experimental results on the Kodak data set and images in real scenes show that the proposed method can reduce color aliasing,reconstruct clear image detail,and the objective criteria with or without reference images are better than the existing color reconstruction methods for RGBW color filter array.

关 键 词：探测器 SONY-RGBW滤光阵列 残差插值 引导滤波 二维离散小波变换 彩色重构 

分 类 号：TN911.73[电子电信—通信与信息系统] P111.49[电子电信—信息与通信工程]