3.1 Validation
To validate our method we extracted root hairs in all fifteen images of
the validation data set and compared the results to the manual
measurements. As illustrated in Figure 2, the distributions of root hair
length obtained with the automatic approach matches the distributions of
manually extracted root hair in all fifteen images. The analysis of the
results showed a strong correlation between automatic and manual results
in mean root hair length (R 2=0.93,p <.001), maximum root hair length
(R 2=0.90, p <.001) and number
of root hairs (R 2=0.63,p <.001).