Recognition of Solar Activities Based on Heliophysics Event Knowledgebase

Solar image conveys obvious active regions and peaceful regions of no activity. Recognizing useful solar activities from solar image is a typical application of image processing in the astronomical research scope. Benefiting from real-time observation data provided by Heliophysics Event Knowledgebase (HEK) of Solar Dynamics Observatory (SDO), this paper proposes a recognition method of solar activities based on HEK. In this method, we gather six kinds of solar activities datas (date,location,area), then we design a scaling transform model for full-disk solar image of corresponding date. Combining location data and area data, we design different gradient thresholds to segment different solar activities regions. Two kinds of boundary identification method are used to locate and recognize solar activities regions respectively. Furthermore, we study the correlation of six kinds of solar image features, and give combinations of features for every solar activity. The method in the paper realizes the precise positioning and efficient recognition, which lies the foundation for further work. Besides, extracting particular combination of features from different solar activities regions also provides a practical approach of constructing a condensed feature set for CBIR system.