GSC Sentinel-2 PDGS STBD - emits - ESA

3.3.2.2.8 Tie Points Collection: Outer Parallelisation by Along-Track FragmentGSC Sentinel-2 PDGS STBDIssue 1 Revision 2 (draft) - 25.07.2010GMES-GSEG-EOPG-TN-09-0031page 29 of 60The final correction model produced by the Correlation Processing Step is the result of aniterative processing composed of two sub-steps: the image matching and the Filtering.Image matching can be parallelised by along-track fragment.ImageRefImageImageMatchingCorrelationGridTie pointsSelectionCurrentCorrectionmodelCorrelationTie pointsfilteringCorrection ModelAdjustmentTie pointListConvergenceCriteriaFinalCorrectionModel3.3.2.2.9 Tie Points Filtering: no parallelizationAs indicated in § 4.2.3.8 and showed in the figure above, Filtering is one sub-step of thecorrelation; correlation is performed within the GPP algorithm by Phases 9 to 10 of theGeo_S2 IAS.There are no possibilities of parallelising the Filtering.3.3.2.2.10 Spatiotriangulation: no parallelizationSpatiotriangulation is performed within the GPP algorithm by Phase 11 of the Geo_S2 IAS.There are no possibilities of parallelising this processing step but its processing time can beassumed negligible.3.3.2.2.11 Level-1B Compression: Parallelisation by Detector and Along-Track FragmentSee § 4.2.2.8. In addition there’s also the possibility of parallelising by detector.3.3.2.2.12 Level-1C Tiles Association: No parallelizationLevel-1C Tile Association is performed within the GPP algorithm by the Tiling_S2 module ofthe Resample_S2.The image footprint is intersected with the UTM tiles footprints in order to identify the UTMtiles composing the target image. Only the metadata are used for this processing step thathas a processing time negligible with respect to the other processing step of Resample_S2.ESA UNCLASSIFIED – For Official Use© ESAThe copyright of this document is the property of ESA. It is supplied in confidence and shall not be reproduced, copied orcommunicated to any third party without written permission from ESA.