Display control device and display layer combination program

A display control device includes: a transparent color information storage unit 5310 that stores transparent color information; a run-length counter 5400 that calculates a run-length specifying the number of consecutive pixels having the same color information; a combination calculation unit 5300 that combines the image data for the plurality of display layers; and a combined image display unit that outputs the combined image data to a display device. If the color information for a total of run-length pixels calculated by the run-length counter 5400 is a transparent color, the combination calculation unit 5300 performs combination by ignoring the image data for the total number run-length of consecutive pixels.