An apparatus includes a contact image sensor (CIS) configured to parallelly output image signals of a plurality of pixels via a plurality of signal lines, an analog frontend (AFE) configured to serially output the image signals of the plurality of pixels output from the CIS by converting the image signal into a plurality pieces of pixel data, an input/output control circuit configured to add reading position information and reading color information to each of the plurality pieces of pixel data, and a direct memory access controller (DMAC) configured to transfer each of the plurality pieces of pixel data to a storage position corresponding to the reading position information and the reading color information such that the plurality pieces of pixel data is stored in consecutive storage positions in an external memory.