Despite the high-tech nature of so much of the Visible Human Project, this essential task is performed in a way reminiscent of an artist's workshop of the late Middle Ages. For example, Engineering Animation, Inc., of Ames, Iowa, won a contract from the NLM to segment images from the chest, or thoracic, cavity of the male. An anatomist would call up a cryosection on the computer screen and, using a mouse pointer, outline each anatomical structure. These delineated edges, and the names of the structures they outlined, then were added in digital form to the database. Engineering Animation and other companies are developing computer algorithms to mechanize, at least in part, the task of segmentation.
Some programs can follow and label specific structures, such as blood vessels.
In addition, the images often include enough ambiguity to require decoding by a human eye. Fat can look like nerve tissue, and both, under certain circumstances, can look like bone. Only someone who knows what he or she is looking at can tell which is which. Consequently, at one point, the company had 15 trained anatomists toiling at this work. The project has given rise to numerous commercial products.