Fecha de publicación: 02/11/1999 Fuente: Wipo "digitalization" A video memory stores a plurality of image data, and an attribute storage means stores image attributes indicating whether or not the respective image data require expansion of a luminance range. An image data conversion means receives an image data digital signal output from the video memory and an image attribute signal output from the attribute storage means. When the image attribute signal provides an instruction to expand the luminance range, the image data conversion means outputs, to a display unit, a display data analog signal representing a higher luminance value, as compared with the display data analog signal to be output therefrom when the image attribute signal provides no instruction to expand the luminance range.