1. A digital image processing apparatus for managing image file names comprising: a digital signal processing unit which generates a captured image file having a file name, the file name including a grouping attribute for the captured image file indicating a group to which the captured image file belongs, wherein during at least one of a group edit of adding a selected file to the group, a group edit of moving a selected file between groups, and a group edit of deleting a selected file from the group, without any user input command requesting to change the file name of the selected file, the digital signal processing unit changes the grouping attribute in the file name to reflect a result of the group edit on the grouping attribute resulting in the grouping attribute indicating the group to which the selected file belongs as a result of the group edit, wherein the captured image file follows a design rule for camera file system (DCF) standard, the file name includes a predetermined digit identifier according to at least one of the manufacturing company and device model, a predetermined digit serial number, a predetermined digit grouping distinguisher and an extension, and the predetermined digit grouping distinguisher comprises a decimal number corresponding to a binary number having an equal number of digits to a total number of groups.