A SIFT-based DEM extraction approach using GEOEYE-1 satellite stereo pairsA SIFT-based DEM extraction approach using GEOEYE-1 satellite stereo pairs Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2020-07-202019enA module for Very High Resolution (VHR) satellite stereo-pair imagery processing and Digital Elevation Model (DEM) extraction is presented. A large file size of VHR satellite imagery is handled using the parallel processing of cascading image tiles. The Scale-Invariant Feature Transform (SIFT) algorithm detects potentially tentative feature matches, and the resulting feature pairs are filtered using a variable distance threshold RANdom SAmple Consensus (RANSAC) algorithm. Finally, point cloud ground coordinates for DEM generation are extracted from the homologous pairs. The criteria of average point spacing irregularity is introduced to assess the effective resolution of the produced DEMs. The module is tested with a 0.5 m × 0.5 m Geoeye-1 stereo pair over the island of Crete, Greece. Sensitivity analysis determines the optimum module parameterization. The resulting 1.5-m DEM has superior detail over reference DEMs, and results in a Root Mean Square Error (RMSE) of about 1 m compared to ground truth measurements.http://creativecommons.org/licenses/by/4.0/Sensors (Switzerland)195Daliakopoulos_et_al_Sensors_19(5)_2019.pdfChania [Greece]Library of TUC2020-07-17application/pdf6.8 MBfree Daliakopoulos Ioannis Δαλιακοπουλος Ιωαννης Tsanis Ioannis Τσανης Ιωαννης MDPI Algorithm Digital elevation model RANSAC Satellite stereo pair SIFT