VIDEO SIGNAL CORRECTING DEVICE

摘要

PURPOSE:To offer a video image with high quality while fog of a picture is eliminated by providing a pulse signal level detection circuit detecting a level of a pulse signal and a video signal frequency characteristic correction circuit correcting the frequency characteristic of the video signal in response to the attenuation of the pulse signal detected by the pulse signal level detection circuit to a video signal receiver side. CONSTITUTION:A pulse signal insertion circuit 12 inserts a pulse signal for a horizontal blanking period of the video signal sent from a television camera 11 at a video signal sender side. A video signal sent through a transmission line 3 is attenuated of its high frequency component at a video signal receiver side and the level of the inserted pulse signal is attenuated. Then a pulse signal level detection circuit 23 detects a level of the pulse signal to generate a control voltage for a frequency characteristic correction circuit 22 in response to the attenuation of the level of the pulse signal and the frequency characteristic of the video signal is made stable by increasing a high frequency emphasis quantity of the frequency characteristic correction circuit 22 when the attenuation of the pulse signal is much and decreasing a high frequency emphasis quantity of the frequency characteristic correction circuit 22 when the attenuation of the pulse signal is less.