Patent ID: 7646930
Filing Date: 2010-01-12
Classification: H04N

Abstract:
1. An edge enhancement system comprising: a horizontal bandpass filter circuit for extracting high frequency signals of a sampled digital image signal in a horizontal direction; a vertical bandpass filter circuit for extracting high frequency signals of a sampled digital image signal in a vertical direction; an adder circuit for adding the high frequency signals generated from the horizontal bandpass filter and the vertical bandpass filter to produce a first high frequency signal; a maximum value detector circuit for detecting the maximum value of the high frequency signals for each sampling in the horizontal and vertical directions to produce a second high frequency signal; a minimum value detector circuit for detecting the minimum value of the high frequency signals for each sampling in the horizontal and vertical directions to produce a third high frequency signal; and a weight adder circuit for determining weights for the first, second, and third high frequency signals based on the value of a difference between the first high frequency signal and either the second or third 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.