I try to refine orthorectification of a World-View 2 image with a set of GCP (17 in total). First i read .geom file in initial image with otbcli_ReadImageInfo and try to refine with otbcli_RefineSensorModel using my GCP. However, resulting orthoimage using refine .geom are more shifted (relative to those GCP) than original images.
Investigating this problem i found that height (z) estimate from otbcli_RefineSensorModel for each GCP are not the same that SRTM data. I use DownloadSRTMTiles application to download srtm data and the geoid link found on the OTB website. Here the result : 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=4222, y=32918, z=215.755, lon=-5.22294, lat=7.16053 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=7818, y=29136, z=215.046, lon=-5.20676, lat=7.17769 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=3015, y=30395, z=224.989, lon=-5.22845, lat=7.17191 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=2146, y=34611, z=227.753, lon=-5.2323, lat=7.15284 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=8825, y=28531, z=207.521, lon=-5.20222, lat=7.18045 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=12964, y=24821, z=252.431, lon=-5.18351, lat=7.19734 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=20593, y=20334, z=263.199, lon=-5.14906, lat=7.2178 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=19766, y=15039, z=259.089, lon=-5.1529, lat=7.24173 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=7572, y=24160, z=221.765, lon=-5.20796, lat=7.20017 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=14997, y=19624, z=238.779, lon=-5.17444, lat=7.22084 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=19236, y=23380, z=237.795, lon=-5.15517, lat=7.20398 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=20686, y=7548, z=259.145, lon=-5.1489, lat=7.27559 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=16714, y=15626, z=244.571, lon=-5.16673, lat=7.23899 2016 Oct 17 16:29:25 : Application.logger (INFO) Adding tie point x=16824, y=22630, z=253.821, lon=-5.16608, lat=7.20731 However, comparing my GCP with the SRTM data at the same location give me those results. otb elevation estimate coord_z from SRTM 215.755027023967 188 215.045595474306 187 224.989075573357 195 227.752914068815 199 207.520907906166 178 252.431061319575 224 263.198903942292 234 259.089167755502 231 221.765367774753 193 238.779180367023 211 237.794649632177 209 259.145216934172 231 244.570667331594 216 253.821387341010 225 I noticed that their is a relative common 28 m offset between those 2 elevation Unfortunately, it seems that OTB cannot support GCP Z coordinate as has been reported in https://groups.google.com/forum/#!searchin/otb-users/gcp$20to$20sensor%7Csort:relevance/otb-users/1Qd1mwk9m7g/QHHO-jUCFAAJ My question remains to know if difference between elevation from my GCP and those estimate by OTB are the source of the shift of the orthorectification. Thanks,¸ Félix -- -- Check the OTB FAQ at http://www.orfeo-toolbox.org/FAQ.html You received this message because you are subscribed to the Google Groups "otb-users" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/otb-users?hl=en --- You received this message because you are subscribed to the Google Groups "otb-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
