Patent ID: 6490003
Filing Date: 2002-12-03
Classification: H04N

Abstract:
A video signal processing apparatus, comprising:a receiver receiving an incoming video signal, said receiver further producing an output video signal in response thereto; a limit setup unit setting up at least one of an upper limit value and a lower limit value for said output video signal; and a limiter supplied with said output video signal from said receiver and further with at least one of said upper limit value and said lower limit value from said limit setup unit, said limiter limiting a level of said output video signal produced by said receiver, by comparing said level of said output video signal according to any of said upper limit value and, lower limit value; wherein said video signal processing apparatus is supplied with said video signal in the form of a digital component signal, and wherein said limit setup unit includes a register holding said upper limit value, said limiter including: a first operational unit supplied with said digital component signal and calculating an amplitude of a color signal contained in an analog composite signal converted from said digital component signal; a second operational unit supplied with said digital component signal and calculating an amplitude of a luminance signal contained in said analog composite signal converted from said digital component signal; a third operational unit multiplying an amplitude factor to a first color difference signal of said digital component signal, said amplitude factor being a ratio of an amplitude of a modified color signal to said amplitude of said color difference signal, said modified color signal having said amplitude determined such that a sum of said amplitude of said modified color difference signal and said amplitude of said luminance signal does not exceed said upper limit value; and a fourth operational unit multiplying said amplitude factor to a second color difference signal of said digital component signal.