Figure 10. Schematic illustration of the image processing protocol used for the non-avian theropod micro-CT scans.

(A) The original image, affected by both high and low frequency noise; segmentation of this image by global or local thresholding techniques will not work. (B) A low-radius median filter is applied to remove high-frequency noise. (C) A large-radius median filter is applied to isolate the low-frequency (background) noise. (D) The low-frequency filtered image in C is subtracted from the high-frequency filtered image in B. (E) A low-radius mean filter is applied, followed by a global high-pass segmentation to produce the final image.