分焦平面偏振成像系统具有结构紧凑、体积小和实时性高等优点,而且一次成像可以获得多个偏振方向的光强响应,已是目前偏振成像的研究热点之一,但该系统的分焦平面结构会降低图像的空间分辨率。为了重构全分辨率的偏振图像以及减弱瞬时视场误差的影响,偏振图像的插值必不可少。为了保护偏振图像的张量结构,提出一种基于张量非负稀疏分解的偏振图像插值算法。首先根据非负稀疏编码理论对4通道的偏振图像块进行张量分解;然后利用非局部自相似约束求解稀疏表示;最后根据采样矩阵将重构的图像块反向映射以获得全分辨率的偏振图像。实验结果表明,所提算法在定量指标和视觉重构效果方面均优于现有的主流算法。

The division-of-focal-plane polarization imaging system has a compact structure, small size, and high real-time performance, and simultaneously can achieve light intensity response of multiple polarization directions in single imaging. It is one of the research hotspots of polarization imaging. The planar structure reduces the spatial resolution of the image. To reconstruct a polarized image at full resolution and reduce the influence of the instantaneous field of view error, interpolation of polarized images is essential. To protect the tensor structure of polarized images, the algorithm for interpolation of polarized images based on non-negative sparse tensor factorization is proposed. First, according to the non-negative sparse coding theory, the four-channel polarization image block is tensor-decomposed. Second, the sparse representation is solved using nonlocal self-similarity constraints. Finally, the reconstructed image blocks are inverted mapped according to the sampling matrix to obtain a full resolution polarized image. Experimental results show that quantitative indicators and image reconstruction effects of the proposed algorithm are more accurate than that of current mainstream algorithms.