Patent ID: 6072539
Filing Date: 2000-06-06
Classification: H04N

Abstract:
A method of steepening edges of a color signal, said method comprising the steps:generating a control signal by performing the following sub-steps:differentiating the color signal to form a first differentiated signal;rectifying the first differentiated signal to form a rectified signal; anddifferentiating the rectified signal to form a second differentiated signal, wherein the second differentiated signal is the control signal; andtemporarily assigning the control signal to the color signal, wherein, in dependence upon the control signal, chrominance values of reference pixels of the color signal are copied on edge pixels of the color signal in such a way that the chrominance values of reference pixels preceding the edge pixels are copied on the edge pixels when the control signal has a positive value, and the chrominance values of reference pixels following the edge pixels are copied on the edge pixels when the control signal has a negative value, characterized in that a chrominance value of a reference pixel is copied on an edge pixel only when the values of the control signal, in an assigned region of the color signal between the reference pixel and the edge pixel, do not have a zero crossing.