A NEURAL NETWORK PROCESSING APPARATUS FOR IDENTIFYING AN UNKNOWN IMAGE PATTERN AS ONE OF A PLURALITY OF INSTRUCTION IMAGE PATTERNS

A neural network processing apparatus calculates an average of the absolute values of differences between the output values of all neurons and a center value whenever the output value of all neurons change, and calculates the difference between the average and the previous average. If the average is larger than a threshold or the previous average, the gain of a function in the network is decreased. If the average is smaller than the threshold or the previous average, the gain of the function is increased. Then the controlled function is set to each neuron and the neural network is activated repeatedly to correctly identify an unknown multivalued image pattern.