1. A digital image processing device for enlarging or reducing an actual original image, said digital image processing device comprising: input means for receiving actual digital original image data representative of an actual original image and a value of a desired magnification/reduction ratio from all possible magnification/reduction ratios with which the actual original image is to be enlarged or reduced; store means for storing a plurality of different image enlarging/reducing manners of processing digital original image data representative of an original image which are inputtable by said input means to thereby achieve enlargement or reduction of the original image with the value of the desired magnification/reduction ratio input by said input means; selection means for automatically selecting one of the plurality of different image enlarging/reducing manners in accordance with data of information on at least one of the input desired magnification/reduction ratio value and the actual original image; and image enlarging/reducing means for processing the actual digital original image data with the selected one of the plurality of different image enlarging/reducing manners to thereby enlarge or reduce the actual original image with the input desired magnification/reduction ratio value, wherein said selection means includes: judge means for judging which one of the plurality of different image enlarging/reducing manners is consistent with the data of information on at least one of the desired magnification/reduction ratio value and the actual original image; and manner selection means for selecting the one of the plurality of different image enlarging/reducing manners consistent with the data of information on at least one of the desired magnification/reduction ratio value and the actual original image.