Sharpening a noisy image by using fuzzy rules

Unsharp Masking (UM) is well known one of the most classical techniques in image enhancement. Due to the presence of the highpass filter, the UM operators very sensitive to noise. In order to conquer this defect, Ramponi has proposed the cubic UM operator which used not only highpass filtering but also edge sensor. By introducing edge sensor, edge enhancement is realized without noise amplification, to a certain extent. It is clear that the combination of edge sensors and highpass filter is effective for sharpening images corrupted by noise. In this paper, we introduce fuzzy rules in the UM operation. Fuzzy rules link the outputs of edge sensor and highpass filter to conclusions about sharpening component of processed image. We show how effectiveness of proposed method by some application results.