A method of combining digital image data from two different images in a printer enables improved precision of alignment of the image data. The method includes copying a word of first image data into a memory buffer, shifting a word of image data by a predetermined bit offset, overwriting a portion of the first image data with shifted bits from the second word of image data, and copying the shifted word of image data into the memory buffer. The printer forms a line of a printed image using the first and second image data in the memory buffer.