Patent ID: 7400775

Claim:
An edge enhancement system comprising: a plurality of bandpass filters for extracting high frequency signals of a sampled digital image signal; an adder for adding the high frequency signals generated from the respective bandpass filters to produce a first high frequency signal; a maximum value detector for detecting the maximum value of the high frequency signals for each sampling to produce a second high frequency signal; a minimum value detector for detecting the minimum value of the high frequency signals for each sampling to produce a third high frequency signal; and a weight adder for determining weights for the first, second, and third high frequency signals on the basis of the value of the first high frequency signal and adding the first high frequency signal to the second or third high frequency signal according to the weights to produce a fourth high frequency signal, wherein when the first high frequency signal has a positive value, the weight adder determines the weights based on the difference between the first and second high frequency signals and adds the first and second high frequency signals according to the determined weights, or when the first high frequency signal has a negative value, the weight adder determines the weights based on the difference between the first and third high frequency signals and adds the first and third high frequency signals according to the determined weights, thus producing the fourth high frequency signal.