基于场景偏振冗余估计的非均匀校正

Polarization redundancy estimation scene-based non-uniformity correction algorithm

由于红外偏振焦平面的异构特性,在非均匀校正过程中需要考虑不同检偏通道的响应差异对整体校正效果的影响,其非均匀校正问题相较同构的普通红外焦平面更为复杂。针对红外偏振焦平面的非均匀校正问题,提出了一种基于场景偏振冗余估计的非均匀校正算法,通过对场景图像和由场景图像计算得到的偏振冗余估计图像进行统计,得到整个焦平面上所有像元响应在统计特性上的差异,然后分通道从两个方向对这些差异进行比较分析,得到更新后的增益校正系数,再通过辐射重定标抑制由于静止场景所造成的鬼影,得到当前状态下相机的增益校正系数。在这个过程中,通过偏振冗余估计评价之前的校正系数,自适应地实现增益校正系数的更新。最后使用真实场景数据进行测试,结果表明本文所提出的非均匀校正算法有效提高了所获取偏振图像的准确性。

Due to the heterogeneous characteristics of the infrared polarization focal plane,it is necessary to take into consideration the impact of the response differences in different bias channels on the overall correction effect in the process of non-uniform correction.The non-uniform correction problem of the infrared polarization focal plane is more complex than that of the ordinary homogeneous infrared focal plane.For non-uniformity correction of polarization focal plane,an algorithm based on scene-based polarization redundancy estimation is proposed.The statistical information between acquired images and estimated images from polarization redundancy is acquired,then the differences in the response of all pixels in the whole focal plane are obtained.By comparing and analyzing the differences from two directions in each polarization channel,we can obtain the updated gain correction coefficients.Then radiometric recalibration is used to suppress the ghost image caused by the static scene,and the gain correction coefficients in the current state are obtained.In this process,the gain correction coefficients are updated adaptively by evaluating the previous correction coefficients through polarization redundancy estimation.Finally,experiments on the real scene data demonstrate the effectiveness of the proposed non-uniformity correction algorithm for polarization images.