ACTIVE REGION DETECTION AND VERIFICATION WITH THE SOLAR FEATURE CATALOGUE

摘要: We describe the automated extraction of active regions (ARs) or plages from European Grid Solar Observations (EGSO) Feature Catalogue using a region-growing technique. In this work, Hα and Ca ii K3 solar images Meudon Observatory EUV SOHO/EIT instrument were used. For better detection accuracy, statistical properties each quarter full disk image are used to define local intensity thresholds for an initial segmentation that helps AR seeds. Median filtering morphological operations applied resulting binary in order remove noise merge broken regions. The centroids labelled region as seeds, which procedure starts. Statistics-based thresholding is also compute upper- lower- threshold values defining spatial extents results obtained with (ATRG) compared day-by-day synoptic maps manually generated by NOAA 2 months 2002 more coarsely over 5-year period. moderate correlation found between our those produced on other data sets reveals need unified definition. As application SFC ARs we present tracking 10484 during its appearance 19–26 October 2003 compare variations Fe xii 195 A wavelengths.