Fig 4. Comparison of normalized area ratios (with respect to total sample area) for RFA core and rim segments as calculated using ground truth (black), local fuzzy (red) and global thresholding (blue) algorithms.

Results are shown for (a) Sample 1 and (b) Sample 2. The local fuzzy thresholding algorithm demonstrates better area agreement with the ground truth segmentation than did the global rigid thresholding. It is worth noting that performing identical image pre-processing before global rigid thresholding did not improve the results.