基于偏振信息的海面太阳耀光抑制

Sun glint suppression from sea surface based on polarization information

太阳耀光干扰严重阻碍遥感领域中目标信息的有效提取,为实现复杂海面背景中水下军事目标的全天候全天时监测,针对无人机载平台,提出基于偏振信息的海面太阳耀光抑制方法。利用太阳耀光和目标信息光的偏振特性差异构建光成分解耦分离模型、选择非饱和偏振图像组解算场景全域偏振信息,使用穆勒矩阵形式的太阳耀光归一化反射率求解太阳耀光的偏振态空间分布;提出光源-水下目标-探测器偏振态传输模型以求解目标信息光偏振度,并根据被动水下成像物理模型,利用水体衰减系数对目标信息光偏振度进行修正;最终实现波动水面的反射太阳耀光抑制。实验结果表明:对于户外真实波动水面场景,耀光抑制图像的区域对比度和图像信杂比相较于90°偏振图像分别提升25.3%和78.4%。本文方法可有效增强太阳耀光干扰下的水下目标表征,从而助力我国挺进深蓝、向海而兴。

Sun glint interference seriously hinders the effective acquisition of object information in the re⁃mote sensing field.In this paper,a sun glint suppression method based on polarization information for UAV-borne platform was presented to realize all-weather and all-time detection of underwater military tar⁃gets in a complex marine background.A light component decoupling model was constructed using the po⁃larization characteristic difference between sun glint and object information light and an unsaturated image set was selected to solve the global polarization information of the scene.Then,the spatial distribution of sun glint polarization state was deduced based on the normalized reflectance of sun glint in a Muller matrix.Further,a source-submarine-detector polarization state transmission model was proposed to estimate the polarization degree of object information light;then,the water attenuation coefficient was used to correct the model according to the physics-based model for passive underwater imaging.Finally,a sun glint sup⁃pression method that is applicable to a wavy water surface was realized.The outdoor experimental results show that the region contrast and signal-to-noise ratio of sun glint suppression image are improved by 25.3%and 78.4%,respectively,compared with those of the 90°polarization image.Our method can ef⁃fectively enhance the characteristics of submarine targets under the interference of sun glint,thus helping our country to better explore the sea.