Specific behavior detection method and system based on pedestrian postures

The invention provides a specific behavior detection method and system based on pedestrian postures. The method comprises the following steps: acquiring an image sequence; performing frame-by-frame processing on each video image sequence, performing pedestrian detection and posture recognition on each frame of image to obtain a probability value list about all types of behavior postures of each frame of image, and storing the frame of image and the corresponding probability value list into a cache queue; summarizing the probability values of the specific behavior postures in the cache queue, and judging whether the specific postures exist in the cache queue or not according to the probability values; dynamically expanding the length of the cache queue until the specific posture does not appear any more, and obtaining candidate segments; and sampling the candidate segments, carrying out classification identification of specific postures, and outputting a detection result. Pedestrian targets are directly concer