针对ZY-3多光谱影像各谱段共视场扫描成像特点,提出基于在轨检校内方位元素的虚拟CCD重成像算法,通过虚拟CCD重成像技术实现单谱段CCD影像的无缝拼接及多谱段的高精度谱段配准。采用河南登封区域及天津区域的ZY-3多光谱影像对ZY-3多光谱相机进行在轨几何检校,利用河北安平区域的30个高精度靶标控制点验证了检校结果的正确性;进一步利用检校后的内方位元素对河北安平区域、兰州区域的ZY-3多光谱影像进行虚拟CCD重成像,采用靶标点验证方法以及高精度配准验证方法对虚拟CCD重成像影像的谱段配准精度验证,谱段配准精度均优于0.2像元。
Fully considering the characteristic of the ZY-3 multispectral camera that all CCD chips of four bands scan through the same field, a novel method is proposed to achieve seamless multispectral images and high accuracy band-to-band registration by re-imaging with virtual CCD. In the experiment, the ZY-3 multispectral camera is calibrated with the ZY-3 images over Henan area and Tianjin area, meanwhile the correctness of the calibration results is validated by 30 high accuracy ground control points (GCPs) in the ZY-3 muttispectral image over Hebei. Further, re-imaging method is applied to the ZY-3 images over Hebei area and Lanzhou area with the virtual CCD calculated from the calibrated interior orientation. Finally, the band-to-band registration is estimated by comparing image coordinates of the same points in different bands. The validity of the proposed method is proved by experimental result which indicates the band-to-band registration accuracy is better than O. 2 pixels.