星载光学多器件多谱段遥感影像高精度几何配准技术研究

Panchromatic and multi-spectral image registration is the basis of remote sensing image applications.After performing ortho-rectification respectively to high resolution camera and multi-spectral camera which share common platform or field of view, the following problems arise: accuracy is low in further registration and fusion process, data acquisition and process of ground control points turn to be complicated, and distortion between multi-spectral becomes inconsistent. In this project, theory, method and implementation of high accuracy geometric registration between panchromatic and multispectral images which share common platform or optical system are supposed to be researched, based on the geometry mechanism of multi-devices and multispectral imaging. According to the study with respect to the geometry relationship of spaceborne optical system, also the precise 3D geometric relationship between multi-devices and multi-spectral, using geometry models of on-orbit optical system which is estimated dynamically based on the technologies of image simulation, images matching of simulation images and real images, furthermore, with combination of ground data and reliable ground control points that is based on edge and object geometry model, relationship of rigorous geometry models for each CCD will be precisely calibrated. High precision geometric registration of multi-devices and multi-spectral images in image space will be achieved through using the unified processing model of multi-device and multi-spectral images by virtual scan lines.

全色和多光谱影像配准是遥感影像应用的基础。针对共平台、共视场的高分辨率相机和多光谱相机，分别做正射校正后，再做配准融合处理的配准精度低，控制数据获取和处理流程复杂，多光谱谱段间畸变不一致等问题。本项目从多器件多谱段成像的几何机理出发，研究共平台、共光学系统情况下的全色、多光谱影像间高精度几何配准的理论、方法和实现。通过研究星载光学系统成像几何关系、多器件多谱段精确三维几何关系，采用基于影像模拟、模拟影像与真实影像的匹配等技术手段动态估计在轨光学系统的几何模型，结合基于刃边和物方几何模型的高精度高可靠控制点和地面数据，精确标定各CCD严密成像几何模型关系，利用虚拟扫描线形成多器件多谱段影像的统一处理模型，实现像方的多器件多谱段影像的高精度几何配准。

项目通过分析星载光学的多器件多谱段的成像几何关系，开展了高精度高可靠控制点获取方法、多器件多谱段影像成像几何关系建模方法、在轨几何关系标定方法的研究，实现多器件多谱段影像一体化几何处理，解决了共平台共视场多谱段影像的高精度几何配准问题。采用资源三号、SJ9A等数据开展了验证试验。项目研究结果有：.1）设计了人工靶标的几何形状，研究了人工靶标的提取方法，靶标像方坐标提取精度0.05-0.1像素，为星载光学多器件多谱段多器件几何关系的解算提供高精度控制数据。（2）研究了光学系统畸变表达的简化模型、物理模型的构建方法。针对小畸变光线系统，实现了资源三号卫星多光谱相机各谱段检校精度优于0.25像元。针对大畸变光学系统，实现了SJ9A的光学相机检校精度优于0.3像元。（3）基于高精度几何关系，采用虚拟CCD重成像算法，实现共平台、共视场的多器件多谱段影像配准，构建高精度通用成像几何模型，能降低后续处理难度。.本项目的研究成果对于国产卫星的多光谱影像质量的进一步提升具有重要的意义，同时也将促进后续卫星的设计和处理的发展。