基于非均匀圆偏振光照射的水下偏振图像处理方法

Underwater Polarimetric Image Processing Method Based on Non-uniform Circularly Polarized Light Illumination

摘要:

针对浑浊水下成像环境,提出了基于非均匀圆偏振光照射的浑浊水下偏振图像处理方法。首先对非均匀圆偏振光照明条件下目标成像和处理遇到的困难进行了分析,并对圆偏振光作为光源的特点进行阐述；其次设计成像环境对水下目标物的偏振图像和可见光图像进行采集。采用基于CLAHE和MSRCR的方法对可见光图像进行预处理,大幅度消除非均匀光照对图像清晰度的影响；依据水下成像的物理模型,考虑到水下目标物反射光的偏振特性,提出了一种基于偏振信息图像融合的图像去雾方法,实验证明该方法能够对偏振信息图像进行优势融合并增强其边缘轮廓；考虑到人眼视觉特性,将偏振信息融合图像与优化后的可见光图像进行融合,最终实现对水下模糊偏振图像的复原。结果表明,该方法实现了偏振图像边缘轮廓及纹理的增强,显著提高了水下图像的质量。

Abstract:

Presented is a method for processing polarised images based on non-uniform circularly polarised light irradiation for turbid underwater imaging environments. First, the difficulties encountered in imaging and processing targets under non-uniform circularly polarised light illumination conditions are analyzed and the characteristics of circularly polarised light as a light source are described. Secondly, an imaging environment is designed to acquire polarised and visible images of underwater targets. A method based on CLAHE and MSRCR is proposed for pre-processing visible light images to substantially eliminate the effect of non-uniform illumination on image sharpness. The method is shown to be able to fuse the polarisation information image and enhance its edge contours, and finally to fuse the polarisation information fused image with the optimised visible light image, taking into account the visual characteristics of human eyes. The results show that the method achieves the enhancement of the edge contours and textures of the polarised images, and significantly improves the quality of the underwater images.