Pattern recognition system

A pattern recognition system comprising:

• at least one pick-up device for converting an image of a picture plane into an electrical signal indicative thereof;
• means for successively taking out of a plurality of electrical signals, each electrical signal being representative of a divided region of the image of the picture plane, region by region from the output of said pickup device;
• means for producing first and second signals indicating rates of changes in brightness along different directions of a region by reference to signals representative of adjacent regions thereto;
• means for producing third signals, each signal indicating the direction of the change in the brightness within each of said regions, from said first and second signals;
• means for encoding said third signals into a code signal by classifying said third signals in accordance with directions of the change in the brightness, counting said signals classified into said respective directions, and digitizing the respective counted values in accordance with a predetermined value;
• means for storing in advance a code signal indicative of an image corresponding to the background of the picture plane;
• and
• means for comparing the code signal from said encoding means with the code signal from said storing means to detect the degree of disagreement therebetween as an indication of an object in the picture plane.