{'fraction_non_alphanumeric': 0.019627085377821395, 'fraction_numerical': 0.0068694798822374874, 'mean_word_length': 4.730337078651686, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Fast Arc Detection Algorithm for Play Field Registration in Soccer Video Mining

This paper presents an LSF-based framework for detecting arcs in broadcast soccer video. The successful identification of the arcs will evidently facilitate the soccer video analysis. The existing methods are not available for all playfield arcs including both the middle field circle and penalty box arcs. A new algorithm is proposed in the paper improved from LSF, called ALSF (advanced least square fitting), which can be used to detect arcs even though they are only 1/4 of eclipses (the same as penalty box arcs). With the improvement, we proposed a new framework to detect the arcs in broadcast soccer video. The proposed method first removes the points of straight lines. Then, all points of each connective area are transformed into a new reference frame to use LSF to get the equations of arcs. Experiments on more than 3 hours broadcast soccer video show the proposed method is effective with above 98% precision and 70% recall.