A Defect Detection Algorithm for Paper Currency Sorting System
Song Liu · Acta Automatica Sinica · 2007
This paper advances a homogeneity based algo- rithm for the detection of scratches and cracks appearing on paper currency.The homogeneity feature of the sensed paper currency image is first constructed to locate the possibly pol- luted pixels.The image registration algorithm is subsequently used to overlay the sensed and reference paper cUrrency images. At last,each possibly polluted pixel on the sensed image is com- pared with its corresponding pixel on the reference image to estimate the contamination level.