1. An image processing apparatus that controls a user interface according to image properties, comprising: a document data acquiring unit to acquire document data; an image recognizing unit to determine the image properties of the document data including a color and a gray level of the document data so as to generate recognition data; and a user interface providing unit to receive the recognition data so as to provide the user interface, wherein operations that can be performed on the document data by the image processing apparatus through the user interface vary according to the recognition data.