PURPOSE: To obtain a hard copy that is close to the image of a display screen which is visually obtained.

CONSTITUTION: A hard copy part 5 receives a hard copy start instruction from a program 4 and then reads the color information on each dot of a display 1 out of a VRAM through a VRAM information reading part 7. At the same time, the part 5 reads the pallet information out of a memory through a pallet information reading part 8. A brightness calculation part 9 calculates with weight the luminance of each dot of the display 1 for each of R, G and B based on the color information given from the part 7 and the pallet information given from the part 8. Then the part 9 converts the color information into the monochromic information according to the total value of R, G and B. A printer output part 10 sends the monochromic information converted by the part 9 to a printer 2 via a computer 3.