Efficient Algorithm to Enhance Lung Lobe Images using Fuzzy Filtering

Preprocessing is done on the CT image of lung for removal of noise. A fuzzy filter is presented for the noise reduction of medical images corrupted with additive noise. The filter operation involves two stages. The first stage computes a fuzzy derivative for eight different directions. The second stage uses these fuzzy derivatives to perform smoothing with the fuzzification and De fuzzification operations along by weighting the contributions of neighboring pixel values. Both stages are based on fuzzy rules. The filter can be applied iteratively to effectively reduce heavy noise. In particular, the shape of the membership functions is adapted according to the remaining noise level after each iteration, making use of the distribution of the homogeneity in the image.