To enhance transfer efficiency of image data by PCIe (Peripheral Component Interconnect Express) in an image processing device.

In an image processing device, a route complex 11 of an integrated circuit 1 comprises buffer units 22-i. The buffer unit 22-i holds a plurality of write requests which are generated in the integrated circuit 1 and have destinations in an integrated circuit 2, when predetermined conditions are satisfied, combines pieces of image data related to the plurality of write requests and transmits the combined image data as one payload in one packet.