The present invention provides a multi-window apparatus which converts the brightness of image data in advance and outputs a synthesized image having the brightness that is most easily seen by the human eye, respectively, on the screen. In the attribute storage means 15, an image attribute indicating whether or not each image data needs to enlarge the luminance range is stored. The image data changing means 16 stores image data output from the video memory 14; The image attribute signal 1b output from the digital signal 1a and the attribute storage means 15 is input, and the image data converting means 16 outputs the luminance when the image attribute signal 1b instructs the expansion of the luminance range. Compared to the case where the enlargement of the range is not instructed, the luminance value of the display data analog signal 1c to be output is increased to be output to the display device 17.
展开▼
