SPRITE CODING DISCRIMINATING METHOD AND SYSTEM FOR VIDEO IMAGE AND STORAGE MEDIUM STORING SPRITE CODING DISCRIMINATION PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide a discrimination method and a system that can discriminate which of sprite/usual coding methods is suitable after short extraction and adaptively select a coding method for each shot. SOLUTION: A frame number discrimination means 11 discriminates that a shot has a sufficient number of frames and the shot has a possibility of adaptability to sprite coding depending on whether or not the number of frames in the short after its extraction exceeds a 1st threshold. A camera parameter discrimination means 12 calculates a camera parameter of the shots having the possibility and discriminates that a camera has a motion and the presence of possibility suitable for sprite coding depending on whether or not any of the camera parameters exceeds a corresponding 2nd threshold. A foreground ratio discrimination means 13 discriminates whether or not the possible shot has a sufficiently smaller foreground part and is suitable for the sprite coding before the coding depending on whether or not a foreground ratio in a binary image of a difference image between a predicted background image and an original image is less than a 3rd threshold value on the basis of a tentative sprite image.