An image processing apparatus includes a reception port capable of receiving a paper document. A discharge port discharges a paper document received from the reception port and serves as an ID card reception port. A conveyance path connects the reception port and the discharge port to each other. A conveyance unit conveys the paper document received from the reception port or the ID card received from the discharge port. An image reading unit, provided on the conveyance path, reads a double-sided image of the paper document or the ID card. An image processing unit matches a first image data output condition obtained by reading, by the image reading unit, the paper document received from the reception port, with a second image data output condition obtained by reading, by the image reading unit, the paper document received from the discharge port.