| 摘要 |
PURPOSE:To obtain easy-to-see profile correction picture without eliminating noise by extracting a high frequency component being a prescribed frequency or over of a luminance signal and limiting its amplitude so as to obtain a profile correcting signal. CONSTITUTION:A luminance signal is fed to two second order high pass filters (HPF)3,4. The 2nd order HPF3 includes a CR circuit so as to extract selectively a high frequency component >=1.7MHz or 2MHz. The amplitude of an output of the 2nd order HPF3 is limited by a clip circuit 5 and a level of a prescribed value or over is cut off. The 2nd order HPF4 extracts selectively a high frequency component >=4-4.5MHz, and a small signal being a prescribed level or below is eliminated by passing its output through a slice circuit 6. An easy-to- see picture is obtained by synthesizing both outputs and the original luminance signal at a synthesis circuit 2. |
