PURPOSE: To prevent forgery of a bank note or the like by discriminating the identity of a special picture so as to reproduce an input picture and controlling the picture reproduction based on the discrimination.

CONSTITUTION: A sensor 1 applies detection of a picture area, pattern recognition or detection of iron content from an original A being an object of picture processing such as copying. Then a discrimination section 2 processes a data detected by the sensor 1 to discriminate whether or not the original is to be subject to picture processing for a bank note or the like. In this case, a dictionary circuit 3 having a picture memory with a learning function is used for the discrimination by the discrimination section 2. Moreover, a signal generating circuit 4 outputs a signal based on the information from the discrimination section 2.