Figure 4.

Example of how the RhizoVision Analyzer skeletonizes root crown images before extraction of measurements. A small region of interest is selected (a) and magnified (b) for demonstration purposes. The thresholded image of the region of interest shows that due to the irregular edges, the generated skeletal structure contains lateral roots that are nonexistent (shown in blue) (c). The skeletal structure of the root is then smoothed to reduce falsely classified lateral roots before line smoothing operation (d). During the line smoothing operation, pixels are either added (shown in red) or deleted (shown in blue) (e). Finally, the skeletal structure of the root after the line smoothing operation has the falsely classified lateral roots removed (f).