The invention discloses a method for automatically detecting the incomplete degree of a bill or paper money. The method includes the steps of A, collecting an image of the bill, thereby obtaining a front face
color image or a front face and back face
color image of the bill; B, judging whether the obtained image of the bill is the front face
color image or the front face and back face color image of the bill or not, carrying out the step C if the obtained image of the bill is the front face color image of the bill, and carrying out the step D if the obtained image of the bill is the front face and back face color image of the bill; C,
cutting out the four corner areas of the front face color image of the bill, and judging whether the corners of the bill are incomplete or not according to the
color difference degree information of the four corner areas; D, carrying out scaling down, binaryzation, left and right mirroring, connected domain marking and
coincidence degree calculation on the front face and back face color image of the bill in sequence, thereby obtaining the
coincidence value of marked targets in the front face and back face color image, and then judging whether the bill is incomplete or not according to the obtained
coincidence value. The method and
system for automatically detecting whether the bill is incomplete or not are high in detection efficiency, high in recognition rate, stable and reliable, and can be widely applied to the intelligent identification field.