Fig. 14

Statistics for the angular error of normal maps recovered using sparse methods. Upper row: sample rendered images with phong_size 10–160, respectively, from left to right. Middle figure: boxplot of the angular error of normal maps under various degrees of specularity. Upper and lower border of blue boxes represent third (Q3) and first quartile (Q1), respectively. Upper and lower whiskers show 1.0 interquartile range (IQR) extended from Q3 to Q1, respectively. Red bars in blue boxes represent medians. At each specularity level, four sparse recovery methods are compared, symbolized by different markers on the median bar: IRL1 (cross), SBL (triangle) and OMP (diamond). Red dots are outliers distributed out of the error bar range. Lower figure: the medians of the angular error