Postures in motion.

<p>(<b>A</b>) Flow chart of the sequential image processing steps to obtain high-resolution trajectories of animal postures. (<b>B</b>) Visual representation of the step schematics in (A) for three different organisms: fruit fly larvae, fish and mice. One can either perform a thinning operation on the binary image of the animal shape to find a skeleton whose endpoints will correspond to head and tail, or alternatively compute contour curvature maxima to determine the position of the head and tail. (<b>C</b>) Illustration of the tracking method for a temporal sequence of postures (blue silhouettes) and head positions (red dots) for a crawling larva, a swimming fish and a walking mouse.