Fig. 6
a The subtracted values (the number of artifacts from the high density material minus the number of artifacts from low density material) according to the threshold values, and b the number of artifact pixels from low- and high-density material; The diamonds above and below represent the 5th and the 95th percentiles of each group, and the squares above and below represent the 90th and the 10th percentiles. Whiskers above and below represent the 75th and the 25th percentiles, respectively. The circle is the median value