使用等效偏移角稀疏测量的面阵相机序贯图像几何校正

天基光学相机实际在轨对地观测成像的畸变需通过几何校正抑制。目前主流面阵相机对地观测获得的小尺寸、高帧频序贯图像很难满足传统几何校正方法逐帧解算对单帧图像控制点数量与空域分布的要求且计算量巨大。针对这一问题，提出一种使用等效偏移角稀疏测量的面阵相机序贯观测图像几何校正方法，将逐帧校正参数解算问题转化为时域稀疏测量条件下等效偏移角信号恢复问题，利用等效偏移角信号时频信息可有效降低对单帧图像控制点数量和空域分布要求。通过高分四号卫星面阵相机在轨实测图像数据验证了所提方法的可行性且其能大大降低序贯图像几何校正处理的计算量。

Sequential image geometric correction of area array camera using equivalent bias angle sparse measurement

The distortion in the imaging of space-based optical cameras for actual in-orbit earth observations needs to be suppressed by geometric correction. At present, the small size and high frame rate sequential images obtained by mainstream area array cameras for ground observation are difficult to meet the requirements of traditional geometric correction methods for calculating the number of control points and spatial distribution of frame-by-frame solution, and the computational complexity is huge. To address this issue, a geometric correction method by using equivalent bias angle sparse measurement for sequential observation image of area-array sensor was proposed. The problem of parameters solution for each frame converted to the problem of equivalent bias angle recovery under the time-domain sparse measurement. The requirement for the number and spatial distribution of control points in a single frame image were reduced by using the time-frequency information of equivalent bias angle signal. Meanwhile, the real image data from the area-array camera of Gaofen-4 satellite was used to verify the validity and low computation of the proposed method.