1. An image processing apparatus comprising: a display; a document image accepting unit for accepting input of a document image obtained by a scanner; a display control unit for causing a preview image of the document image accepted by said document image accepting unit to be displayed on said display while being moved in a prescribed direction in a sequential manner; an operation accepting unit for accepting an operation of image editing for document images, which are series of document images accepted by said document image accepting unit, including the document image corresponding to the preview image moving on said display; and an editing unit for performing the image editing accepted by said operation accepting unit for said document images.