The invention relates to the technical field of behavior
feature recognition, in particular to a
pattern recognition system for fish abnormal behaviors in an
underwater video, and the
system comprises a fish body skeleton positioning module which is used for retrieving a fish body pixel region in an
underwater video frame, positioning a head, a plurality of spine midpoints and a
tail fin base, and obtaining a fish body coordinate
point set. According to the method, frame-by-frame positioning and key point extraction are carried out on a fish body pixel region in an
underwater video frame, a continuous skeleton chain is formed by coordinates of a head, a spine midpoint and a
tail fin base part, and a skeleton dynamic sequence with a time attribute is generated based on spatial position information, so that reconstruction of an overall motion structure of a fish body is realized; and further, analysis
processing is carried out on the connecting line angle between the skeleton key points, the angle change rate and the skeleton curvature, so that the
kinematics description of the dynamic structure of the fish body is refined, meanwhile, complete attitude
time sequence information is constructed, and the recognition capability of local deformation is improved.