Image processing apparatus and image processing method

An image processing apparatus, having an image combining function in which a plurality of pages of image data is scanned, the plurality of pages of the scanned image data is combined into one page, and the combined image data is printed on a single sheet of recording paper, the image processing apparatus comprising:

• a scanner that scans the plurality of pages of the image data, at least one of the plurality of pages of the image data having a size different from a size of another page;
• a printer that prints image data on a sheet of the recording paper;
• and
• a controller that determines the image data having a largest size among the plurality of pages of the scanned image data, to determine a size of a sheet of the recording paper, based on the determined largest size, the determined size of the sheet of the recording paper based on a product of the determined largest size and a number of the plurality of pages of the scanned image data, to combine the plurality of pages of the scanned image data into one page, and to print the combined image data on the single sheet of the recording paper having the determined size.