1. An image forming apparatus comprising: input means for receiving image data, the image data comprising a plurality of input dots of image data, each input dot having a corresponding dot position in a window of a predetermined shape; jaggedd edge reducing means for reducing jagged edges in the image data said jagged edge reducing means comprising a neural network for receiving image data in a window, the window having a center dot, the neural network outputting correction data, in response to the window image data, correcting the corresponding dot position and size for the center dot in the window based on the correction data, simultaneously generating subdivided dots of each of said input dots subject to reducing jagged edges thereof to reduce a jagged edge present in said image data, and outputting a smoothed image on the correction of the center dot; and means for replacing said generated subdivided dots for each input dot subject to reducing a jagged edge thereof using the neural network.