Diagnosis of Skin Lesions Based on Dermoscopic Images Using Image Processing Techniques

Great effort has been put into the development of diagnosis methods for the most dangerous type of skin diseases—melanoma. This paper aims to develop a prototype capable of segment and classify skin lesions in dermoscopy images based on ABCD rule. The proposed work is divided into four distinct stages: (1) preprocessing, consists of filtering and contrast enhancing techniques, (2) segmentation, thresholding, and statistical properties are computed to localize the lesion, (3) features extraction, asymmetry is calculated by averaging the calculated results of the two methods: entropy and bi-fold. Border irregularity is calculated by accumulate the statistical scores of the eight segments of the segmented lesion. Color feature is calculated among the existence of six candidate colors: white, black, red, light-brown, dark-brown, and blue-gray. Diameter is measured by the conversion operation from the total number of pixels in the greatest diameter into millimeter (mm), and (4) classification, the summation of the four extracted feature scores multiplied by their weights to yield a total dermoscopy score (TDS); hence, the lesion is classified into benign, suspicious, or malignant. The prototype is implemented in MATLAB and the dataset used consists of 200 dermoscopic images from Hospital Pedro Hispano, Matosinhos. The achieved results show an acceptable performance rates, an accuracy 90%, sensitivity 85%, and specificity 92.22%.