Patent ID: 6597407
Filing Date: 2003-07-22
Classification: H04N

Abstract:
A contour correction circuit comprising:(a) a delay circuit for delaying an input video signal; (b) a corrected waveform generating circuit for generating a contour correction signal from the input video signal; (c) a variable amplifier for controlling an amplitude of the contour correction signal; (d) a contour control circuit for outputting a gain control signal for controlling a gain of the variable amplifier; and (e) a first adding circuit for adding an output signal from said delay circuit to an output signal from a variable amplifying signal from said variable amplifier; wherein said contour control circuit further comprising: (d-1) a scene determination circuit for generating an output signal response to an amplitude change in an edge portion of the input video signal; and (d-2) a control signal generating circuit for generating the gain control signal so that (i) when said output signal of said scene determination circuit is greater than a predetermined level, then, as an amount of amplitude change of the input video signal increases, an amount of contour correction decreases; and (ii) when said output signal of said scene determination circuit is less than said predetermined level, then, as said amount of amplitude change of the input video signal increases, said amount of contour correction increases.