| 摘要 |
PURPOSE:To make the visual approximating job easy for the gradation of black- and-white hard copy in contrast with the expression with a color display, by providing a weighting circuit for each combination signal, in converting a color video signal into a black-and-white signal. CONSTITUTION:Three primary color signals R, G and B provided for a color display device are introduced to a clampers 4-6 reproducing DC components of signals via input buffer amplifiers 1-3 received with a high input impendance, the outputs are given to comparators 13-15 and converted into the primary color signals of logic level. Seven combined outputs are obtained at a decoder 16, each output is synthesized at a synthesis circuit 10 via weighting circuits 17-23 to obtain an output signal HCP for black-and-white hard copy. |
