A digital still camera produces size-reduced image data of a JPEG file, which is converted into printable image data of a TIFF file according to a converting parameter. In the digital still camera, raw image data (CCD-RAW) is produced, corresponds to the JPEG data, and has an unreduced format. Images of the JPEG data are displayed in a playback manner. A customer order of an image among the displayed images to be printed is processed. JPEG data associated with the image of the customer order is adjusted according to a standard adjusting parameter. The standard adjusting parameter is modified into a first adjusting parameter. Raw image data associated with the image of the customer order is converted into TIFF data by image conversion according to the first adjusting parameter and/or a standard converting parameter being preset.