IMAGE DATA OPERATION PROCESSING APPARATUS

An image data operation processing apparatus having a controller for transferring specified image data and generating various processing commands in accordance with an operation command input from an external unit. The controller reads out the specified image data from a plurality of image memories for storing n-bit, image data, and outputs the readout data to an operation unit. The operation unit includes an image data processor capable of performing a linear combination operation and obtaining the absolute value of a difference, and a look up table unit. The look up table unit includes a table generator, a conversion processor for receiving image data, the total number of bits of which does not exceed a maximum of m bits (m is an integer satisfying 3n/2.ltoreq.m<2n) and for performing data conversion, and a table memory. The table generator generates a table in response to a table generation command from the controller and stores it in the table memory. When image data is transferred by the controller and a linear combination command or a subtraction command is generated therefrom, the image data processor looks up the table memory in response to a data conversion command from the controller and obtains data corresponding to the input image data.