Inner FOV stitching algorithm of spaceborne optical sensor based on the virtual CCD line
虚拟CCD线阵星载光学传感器内视场拼接

To obtain bigger swath width,most high-resolution linear push-broom imaging systems use a many CCD chip configuration instead of a single chip configuration.The CCD chips cannot be fixed linear in the focal plane.The question "how to stitch the images obtained by the CCD chips to a seamless single image?" becomes important in the processing of high-resolution satellite images(HRSI).In this paper,an algorithm of inner filed-of-view(FOV) stitching based on the virtual CCD line is shown.With the derivation of the infection to stitching precision caused by height precision,we found that if the virtual CCD is installed near the real CCD,the average height could be used for the stitching algorithm without a loss of precision;otherwise,precise DEM data will be needed.Data from the ALOS/PRISM sensor has been used as test data to verify the algorithm.Through the stitched forward,nadir,and backward images,no position mistakes can be found.A rigorous geometry model of the stitching images also has been made.Comparing the forward intersection results and the original images rigorous sensor model and the stitching images rigorous geometry model,the stitching images has the same orientation accuracy.The ALOS/PRISM images can be stitched without DEM by this method,and the precision of stereoscopic mapping is not being reduced.This method also can be used for combining images from digital aerial cameras.