Video signal processing and video camera

摘要

A video signal is supplied to a contour signal generating circuit (15-29). The contour signal produced at the output (28, 29) thereof is Gamma corrected multiplying (30) the contour signal with a Gamma correction signal produced by a correction circuit (50, 51). The correction circuit (50, 51) comprises a low pass filter (50) which attenuates the high frequencies of the video signal, and a Gamma inclination circuit which selects a linear Gamma correction segment for high frequencies and a non-linear correction function for low frequencies. The video signal is also Gamma corrected in a Gamma correction circuit 34 in which high frequencies are corrected by a linear function and low frequencies are corrected by a non-linear function. The Gamma corrected contour signal is added to the Gamma corrected video signal in an adder (52). Aliasing is avoided due to the Gamma correction of the contour signal and yet suitable emphasis of image contours is achieved. <IMAGE>