DIGITAL PROCESSING CIRCUIT OF VIDEO SIGNAL

PURPOSE:To reproduce a half tone with a simple constitution by outputting a digital signal in accordance with the result to compare successively at the prescribed period respective levels of a three primary colors signal with one of plural mutually different reference levels. CONSTITUTION:Respective red, green and blue signals from an NTSC decoder 1 are compared with the voltage derivated to the output terminal of a change- over switch circuit 16 in comparators 3, 4 and 5. Reference voltage Vr2 and Vr3 are impressed to two input terminals of the change-over switch circuit 16, and this is derivated alternately selectively at every 1H by a control signal. Thus, when red, green and blue signals are outputted in the section of continuous 2H, digital data with different binary levels are obtained, the arrangement of colors on two scanning lines obtained at the section of 2H goes to be different, and a neutral tint can be macroscopicly obtained.