航天CMOS相机动态画幅成像瞬时影像像旋分析

Instantaneous Image-Rotation Analysis for Dynamic Format Imaging of Space CMOS Camera

为定量分析动态漂移时的像旋对成像质量影响的程度,基于动态环扫成像理论,建立一种静态影像与动态漂移间的融合模型。然后结合面阵CMOS相机成像特点与动态运动特性,提出对像旋矢量进行分解处理再融合的仿真模拟方法,设计了一种动态环扫画幅影像像旋仿真分析方法,获取了不同动态成像参数下的模拟影像。最后利用成像幅宽、地面分辨率、成像系统信噪比、峰值信噪比及结构相似性等指标对模拟影像进行定量评估分析。仿真结果表明,相机曝光时间越长,成像系统信噪比越高,像旋越大,成像质量越差,结构相似性越小。研究结果可为未来多种动态成像模式设计中减小像旋影响、提高相机成像质量提供有效的参考。

To quantitatively analyze the influence of image-rotation on the image quality during dynamic drift,a fusion model comprising a static image and dynamic drift is proposed based on the dynamic circular scanning imaging theory.A simulation method of image-rotation vector decomposition and refusion is designed based on the imaging and dynamic motion characteristics of area array CMOS camera.Further,an image-rotation simulation analysis method of the dynamic circular scanning format image is designed.Thus,all simulated images under different dynamic imaging parameters are obtained.Finally,the parameters of image width,ground resolution,signal-to-noise ratio,peak signal-to-noise ratio,and structural similarity are used to quantitatively evaluate and analyze the simulated images.Simulation results show that a longer exposure time of camera corresponds to a higher signal-to-noise ratio of the imaging system,larger image rotation,worse imaging quality,and smaller structural similarity.The results of this research can provide an effective reference for reducing the influence of image-rotation and improving the image quality of the camera in the future design of multiple dynamic imaging modes.