期刊名称:ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN:2194-9042
电子版ISSN:2194-9050
出版年度:2004
卷号:XXXV Part B1
页码:453-459
出版社:Copernicus Publications
摘要:As part of CNES-ISPRS HRS Study Team investigation, SPOT-5 HRS along-track stereo data over Montmirail (France) and Melbourne (Australia) test sites were evaluated using the modified IRS-1C/1D stereo photogrammetric software Saphire and PCI Geomatica Orthoengine (version 9) software. Both the stereo pairs were processed using the four corners and one center pixel planimetric coordinates for each individual image as control points. The linearly interpolated satellite state vectors were used in the space resection module of the modified Saphire software to compute the updated attitude angles based on the control point coordinates, separately for each image. Conjugate points were automatically identified using interest points based hierarchical image matching. Using the space intersection module, (planimetric coordinates and) heights were computed at each conjugate point. These were interpolated to generate a uniform DEM grid of required spacing. For Montmirail, the DEM generated was compared with the two reference DEMs provided in Lambert II projection with NTF datum in Clarke 1866 ellipsoid, which are accurate to about 1 m. For Melbourne, the DEM could not be generated using the PCI Geomatica possibly due to large cloud patches. It is observed that without using any control points, the modified Saphire software could achieve an accuracy of 20 m at 89% (10 m at 75% and 5 m at 58%) of the DEM points in the case of Montmirail. The results could be improved if manual interaction for interactively increasing the density of conjugate points and identifying break-lines are introduced in Saphire. Availability of a near-nadir image would also help reduce the occlusions that occur in high slope areas
关键词:SPOT5; stereo imaging; digital elevation model; DEM evaluation; IRS-1C/1D stereo software