| 摘要 |
PROBLEM TO BE SOLVED: To reduce the quantity of the so-called flicker interference, such as DC fluctuation through a comparatively simple method by detecting and adding a signal corresponding to the difference of average luminance level displayed on a CRT. SOLUTION: A video signal processing circuit 10 is composed of a 1st low-frequency component detection part, a 2nd low-frequency component detection part provided with a 2nd low-pass filter(LPF) 4 for inputting a video input signal, subtracter 5 and adder 6. The 1st low-frequency component detection part is provided with a γ-transforming part 1 for transforming the video input signal with γ characteristics, 1st LPF 2 and inverse transforming part 3 for inversely transforming the output of that filter with γ<-1> characteristics. The substracter 5 subtracts the output of the inverse γ-transforming part 3 as the output of 1st low-frequency component detection part from the output of 2nd LPF 4 as the output of 2nd low-frequency component detection part. Then, the adder 6 adds the output of the substracter 5 and the video input signal and outputs the result. |
