To provide a technology shortening the total time required for RIP (raster image processing) on image data received from a plurality of terminals by optimizing the start timing of RIP.

When receiving terminal information showing a transmission source together with image data, the timing of RIP start order to the image data being received is switched based on the terminal information received together with the image data being received, and RIP is applied to the image data according to the RIP start order. The reception speed of the image data is measured, and the timing of RIP start order to the image data is switched based on the measured reception speed to apply RIP to the image data according to the RIP start order. The timing of RIP start order is made during reception or after the termination of receiving the image data, and is distinguished according to the terminal information and reception speed.