Editing Computer vision (section)

===Image-understanding systems===
Image-understanding systems (IUS) include three levels of abstraction as follows: low level includes image primitives such as edges, texture elements, or regions; intermediate level includes boundaries, surfaces and volumes; and high level includes objects, scenes, or events. Many of these requirements are entirely topics for further research.

The representational requirements in the designing of IUS for these levels are: representation of prototypical concepts, concept organization, spatial knowledge, temporal knowledge, scaling, and description by comparison and differentiation.

While inference refers to the process of deriving new, not explicitly represented facts from currently known facts, control refers to the process that selects which of the many inference, search, and matching techniques should be applied at a particular stage of processing. Inference and control requirements for IUS are: search and hypothesis activation, matching and hypothesis testing, generation and use of expectations, change and focus of attention, certainty and strength of belief, inference and goal satisfaction.<ref>{{Cite book|title = Encyclopedia of Artificial Intelligence, Volume 1|last = Shapiro|first = Stuart C.|publisher = John Wiley & Sons, Inc.|year = 1992|isbn = 978-0-471-50306-4|location = New York|pages = 643–646}}</ref>