Method for Crater Detection From Martian Digital Topography Data Using Gradient Value/Orientation, Morphometry, Vote Analysis, Slip Tuning, and Calibration

Recently, all the craters from the major currently available manually assembled catalogs have been merged into the catalog with 57 633 known Martian impact craters. This paper presents a new crater detection algorithm (CDA) for the search of still uncataloged impact craters. The CDA is based on fuzzy edge detectors and Radon/Hough transform and utilizes digital topography data instead of image data. The critical parts of the method providing increased accuracy are as follows: (1) gradient-value/orientation-based techniques; (2) automated morphometry measurements of depth/diameter ratio, circularity, topographic cross-profile, rim, central peak, and radial range where the crater is preserved; (3) circularity analysis of votes in parameter space; (4) slip tuning of detected craters´ parameters; and (5) calibration which partially compensates differences in morphology between small and large craters. Using the framework for the evaluation of CDAs, in comparison with prior work, the proposed detector shows the following: (1) significantly larger area under the free-response receiver operating characteristics (AUROC) and (2) significantly larger number of correct detections. Using the Mars Orbiter Laser Altimeter data as input, the CDA proposed numerous candidates for GT-57633 catalog extension. After the manual survey of all proposed craters and rejection of false detections, 57 592 impact craters were confirmed as correct detections. The accompanying result to the CDA is a new GT-115225 catalog.