The color of the figures printed with photo-induced discoloration ink has a special change when the light irradiates a bank note from different angles. This is an important method to identify if a bank note is faked or not. In this paper

an automatic recognition method focusing on photo-induced discoloration printed ink technique is proposed to recognize the fakeness of bank notes. The bank note automatic recognition system mainly consists of DSP

FPGA and color CCD camera. The system pre-handles video data stream by FPGA

sequentially switches among different memory areas and completes the real-time collection and storage of bank note image data. According to the characteristics of the image data

based on the concept of SOPC

FPGA integrates Nios soft core and implements parallel processing. Then DSP completes the recognition process of a bank note. The feasibility and effectiveness of the proposed automatic recognition method is verified by various experiments.