Disclosed are an image processing method and apparatus whereby the capability of coding/decoding processing accompanied by learning is improved, this also making it possible to achieve high-speed image formation processing without error. The apparatus includes a coder for generating coded data by arithmetically coding image data, a counter for counting the number of times learning is performed by the coder, and a comparator which, when a count recorded by the counter attains a value stored in a register, stops the learning operation executed by the coder.