To simplify data transfer in correcting image data and also control over a transfer timing and enhance general versatility in receiving image data and outputting to a print engine.

This apparatus has an image input 205 which includes input memories 201-203 for arranging image data to a correction process window 203 and an input timing control 204 for updating image data of the input memories synchronously with a system clock CLK, data corrections 206, 207 for generating an image data 2 conforming to a content distribution of the image data of the window 203, a correction output timing control 208 for outputting the image data 2 synchronously with the system clock CLK, an output memory 211 for storing the image data 2, and a synchronous control 212 for sending an image data 3 of the output memory synchronously with synchronous signals WCLK, FGATE, PMSYNC of a printer engine 106.