Fig. 5
a, b Scatter plots of the cross sectional area segmentation: manual versus semi-automatic. a Spatial resolution achieved by zero padding for manual segmentation: (86×86) μ m 2; semi-automatic segmentation: (21×21) μ m 2. b Same spatial resolution for manual and semi-automatic segmentation. c, d PWV calcualtions based on the data shown in a, b respectively