Patent ID: 7554548

Claim:
A gamma curve generation method of generating a curve passing through multiple consecutive control points as a gamma curve used for gamma correction of an image signal, the gamma curve generation method comprising the steps of: (a) selecting each set of three consecutive control points among the multiple consecutive control points; (b) forming a cubic curve passing through the selected three consecutive control points; and (c) combining all cubic curves formed in the step (b) to generate the gamma curve, the step (b) setting the selected three consecutive control points to a first control point, a second control point, and a third control point in a sequential order and specifying the cubic curve that passes through the first control point, the second control point, and the third control point and has a tangent of a gradient G at the second control point, which satisfies Equation (1) given below: G =  G ⁢ ⁢ 12  × G ⁢ ⁢ 23 +  G ⁢ ⁢ 23  × G ⁢ ⁢ 12  G ⁢ ⁢ 12  +  G ⁢ ⁢ 23  ( 1 ) where G 12 denotes a gradient of a straight line connecting the first control point with the second control point and G 23 denotes a gradient of a straight line connecting the second control point with the third control point, wherein the above steps are performed by a processor.