FIG. 4.

Computing LBP. In step 1, for each pixel in the tumor ROI, a 3 × 3 patch covering the pixel is extracted. In step 2, we compare the pixel intensity of the surrounding pixels with the center pixel. The comparison results are either 1 (the surrounding pixels are more intense) or 0 (the surrounding pixels are less intense) and are recorded in a 3 × 3 table. In step 3, the results in the table form in the indicated direction a binary string, which is then converted to a decimal number. Eventually, each pixel has a decimal number describing its binary pattern. We use the normalized histogram of these decimal numbers as the LBP texture features.