搜索

x
中国物理学会期刊

基于稀疏低秩特性的水下非均匀光场偏振成像技术研究

CSTR: 32037.14.aps.70.20210314

Clear underwater vision in non-uniform scattering field by low-rank-and-sparse-decomposition-based olarization imaging

CSTR: 32037.14.aps.70.20210314
PDF
HTML
导出引用
  • 针对浑浊水体偏振成像时由于强散射作用导致的背景散射光分布不均匀且目标信息被淹没, 无法有效解译, 难以实现清晰化成像的问题, 提出基于稀疏低秩特性的水下非均匀光场偏振成像技术. 该技术利用散射光场中偏振信息的共模抑制特性消除非均匀性, 结合水下散射光场中背景信息纹理单一、信息相关性高以及目标信息空间占比小的特点, 建立偏振域的稀疏-低秩信息分析处理模型, 有效分离目标和背景信息, 重建高对比度清晰目标图像. 实验结果表明, 基于稀疏低秩特性的水下非均匀光场偏振成像技术不仅能够有效地提升浑浊水下图像的对比度, 复原细节信息, 而且能够有效地抑制非均匀强散射, 在水下偏振成像领域具有良好的应用前景.

     

    Underwater imaging plays a critical role in marine rescue, seabed resource exploration, underwater archaeology, etc. by providing human-vision-system-friendly information. A variety of approaches have been exploited to realize clear underwater imaging. Noticeably, underwater polarization imaging has attracted attention due to its simple imaging system and clear vision. It can remove the backscattered light from degraded image and recover abundant high-fidelity information of target. Descattering is conducted by using the difference in polarization characteristics between the target and background. A classical underwater polarization imaging method is presented by Schechner Tali T, Schechner Y Y 2009 IEEE Trans. Pattern Anal. Mach. Intell. 31 385, in which the differential polarization characteristics of backscattered light and target light are used to recover clear image. More researches were conducted including Huang et al.’s research Huang B J, Liu T G, Hu H F, et al. 2016 Optics Express 24 9826, Liu et al.’s study Liu F, Han P L, Wei Y, et al. 2018 Opt. Lett. 43 4903, etc.
    However, in the polarization imaging methods, the uniform underwater backscattered light and polarization parameters over the whole image are usually assumed. In most practical applications, these assumptions cannot hold true. Therefore, the inaccurate estimation of backscattered light makes it difficult to completely descatter an image, leading many methods to fail to detect the target in non-uniform turbid water.
    In this study, we propose a low-rank-and-sparse-decomposition-based polarization imaging combined with common mode rejection feature of polarization information in scattered light field to eliminate non-uniformity and scattering caused by severe scattering during active polarization imaging of turbid water. The backscattered light is highly reduced and the information contained in background is single and highly correlated. It conforms to the low-rank characteristics of the image. What is more, the target in underwater scene occupies a relatively small proportion, which conforms to the sparsity characteristics of the image. Therefore, combining the low-rank characteristics of backscattered light with the sparse characteristics of target information light, we separate them through low-rank and sparse matrix decomposition to recover clear underwater image. Both experimental and objective image quality evaluation results demonstrate the validity of the proposed method.
    The proposed method works well in improving polarization vision in non-uniform turbid water, which is due to its ability to make the underwater scene uniform and the target and background information separated through their distribution difference of polarization characteristics. It possesses potential applications in turbid water imaging.

     

    目录

    /

    返回文章
    返回