The initial processing steps of maize stalk transections. A) Original, unprocessed images of four stalk transections. The two on the left are the same genotype. The two on the right are the same genotype but different from those on the left. B) Segmenting all non-background objects by a simple thresholding technique identifies the stalk samples and smaller non-stalk objects such as scratches and debris. C) A filtering step based on object size and shape results in a binary image consisting of background and stalk samples. D) A crop box centered on each of the stalk objects is placed on the original image to allow the user to make adjustments to the scenes to be processed.