Patent ID: 7576894

Claim:
An image signal sharpening device for receiving an image signal input, performing a sharpening treatment using the data sampled from the object edge of the image signal input through a detection window and then outputting an image signal output, wherein a detection period is sampled from a detection window of the image signal input to produce n sample points wherein n is a positive integer, the device comprising: an object edge maximizing unit for selecting the largest value among a first sample point, a middle sample point, and an n th sample point sampled within the detection window and outputting a maximum value signal; an object edge minimizing unit for selecting the smallest value among a first sample point, a middle sample point, and an n th sample point sampled within the detection window and outputting a minimum value signal; a switch-point generator for determining the locations of the maximum value signal and the minimum value signal within the detection window according to a switch-point signal output based on the image signal input; a signal processing unit for sharpening the image signal input according to the maximum value signal, the minimum value signal, and the switch-point signal; a confidence checking unit for determining the correctness of the detected object edge of the image signal input according to the maximum value signal, the minimum value signal, and the switch-point signal, and then outputting a selection signal; and a selection device for outputting either the output from the signal processing unit or the image signal input according to the selection signal, wherein the middle sample point is the [(n+1)/2] th sample point if n is an odd number.