IMAGE REGISTRATION USING TERRAIN RELIEF CORRECTION BASED ON THE RIGOROUS SENSOR MODELS
Multiple CCDs are used in space-borne camera system to have multiple bands and/or to have wider swath even in one band. Due to design constraints, the multiple CCDs may be placed at different position on the effective focal plane. In such case, each band or each CCD in a band has different look angle, and hence suffers so-called "parallax effect" when registration between images from different CCD is required. Since the parallax effect is a function of height of the target when the baseline is fixed, the displacement of each target for the registration differs from target to target depending on the height of each target in the images. Hence, the registration between images from different CCDs cannot be achieved using simple affine transform, and rather requires higher order matching methods, such as local warping. In this paper, we suggest the band registration method which includes the compensation of terrain relief by sensor model with DEM data. Since the parallax effect is compensated in this approach, the simpler matching strategy can be adopted for the robustness of algorithm. In the proposed approach, the slave image is resampled to virtual CCD geometry, which has same geometry with master image. In order to realize such approach, accurate camera model for each band and DEM data were used. The difference of proposed approach with conventional ortho-rectification is that the geometry of master image is kept. The experiment results demonstrated that proposed method can effectively correct the displacement caused by parallax effect.