二维指向镜像旋校正及拼接方法  

Two-Dimensional Pointing Mirror Rotation Correction and Stitching Method

作　　者：李丹丹 马超 柴孟阳[1] 孙德新[1,2] Li Dandan;Ma Chao;Chai Mengyang;Sun Dexin(State Key Laboratory of Infrared Physics,Shanghai Institute of Technical Physics,Chinese Academy of Sciences,Shanghai 200083,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院上海技术物理研究所红外物理国家重点实验室,上海200083 [2]中国科学院大学,北京100049

出　　处：《光学学报》2024年第12期217-224,共8页Acta Optica Sinica

基　　金：国家自然科学基金重大项目(42192582);国家重点研发计划(2022YFB3902000);中国科学院战略性先导科技专项(XDB0580000);中国科学院青年创新促进会(2020242&2023246)。

摘　　要：在卫星探测领域,为了扩大探测器的成像视场,研究人员提出了二维指向镜配合凝视成像的观测模式,二维指向镜具有体积小、质量轻的特点,能够实现全方位探测。由于二维指向镜绕俯仰轴和方位轴旋转,而探测器像面固定不动,这种工作模式会引入像旋误差,如不加以校正将造成探测目标的离轴信息失真,无法得到探测目标的准确方位信息。为此,本文提出了一种二维指向镜像旋校正方法,根据像旋产生的光学机理,构建二维指向镜成像模型,通过对该模型的逆向推导实现像旋校正。此外针对卫星探测领域对大视场成像的需求,本文提出了一种像旋校正图像拼接方法,该方法不受图像之间重叠区域大小的限制,能够得到缝合紧密、自然的大视场图像拼接结果。最后,用探测器采集了一组九宫格像旋数据,并进行了像旋校正和图像拼接,结果表明,所提方法能够成功校正图像的像旋畸变并得到完整的大视场拼接图像。Objective In remote sensing devices,image rotation has become a crucial factor affecting imaging results,but if not corrected,it will lead to off-axis distortion of detected target information,preventing the acquisition of accurate azimuth information.Current image rotation correction methods mainly include optical de-rotation,mechanical de-rotation,and digital de-rotation.However,both optical and mechanical de-rotation methods require the addition of new devices to the original imaging system,imposing high demands on device weight and motion accuracy.Therefore,we propose a digital de-rotation algorithm.Meanwhile,the large field-of-view infrared images are advantageous for obtaining abundant terrain information.Thus,it is necessary to stitch the corrected rotated images after correction.However,there is currently no well-established solution for the challenging task of stitching rotated and corrected images.Existing image stitching methods demand high image quality and a significant number of matching points between images.The overlapped areas between the rotated images acquired by the detector are typically small to expand the field of view.Thus,it is essential to develop a stitching algorithm specifically designed for rotated and corrected images.Methods We propose a two-dimensional pointing mirror rotation correction and stitching method.Firstly,the image rotation correction algorithm is based on the optical imaging principles of the detector.It builds the imaging model of the two-dimensional pointing mirror,as shown in Eq.(5).Subsequently,the image rotation correction method is derived by reverse deduction of this model,as shown in Eq.(10).Then,the stitching algorithm for the image rotation-corrected images is shown.This method relies on a simulated field-of-view model based on information such as the elevation angle,azimuth angle,and detector specifications of the two-dimensional pointing mirror(Fig.4).By employing the model to determine the pixel relationships between models,the positional information betwe

关 键 词：二维指向镜 像旋 图像拼接 大视场 

分 类 号：TP73[自动化与计算机技术—检测技术与自动化装置]