| 摘要 |
PURPOSE:To change the striking dot density of a printer in response to the luminance of colors and to print out a black/white image which can be easily recognized and understood, by producing the luminance signal corresponding to the luminance of each picture from the 3 primary color signals of each picture element of a color picture. CONSTITUTION:The position information of picture elements given from an upper device is fed to an address decoder 2 via a signal line 8. The position information is decoded and divided to X and Y coordinates of a color picture to be supplied to a printing elemint driving part 3 and a paper feed driving part 4. At the same time, the color information of picture elements is applied to a converting part 1 via a signal line 7. The 3 primary color signals are converted into the striking dot signals through the part 1. These 3 primary color signals corresponding to the color information are supplied to the part 4, and the striking dot signal corresponding to the luminance of each picture is produced on the basis of the position information given form the decoder 2. Then a printing mechanism 5 is driven. A paper feeding mechanism 6 is driven through the driving part 4 to change the striking dot density of a printer in accordance with the luminance of colors. Thus a black/white picture which can be easily recognized and understood is printed out. |
