Catalogue of Artificial Intelligence Techniques
Author(s): T.P. Pridmore, S.R. Pollard, S.T. Stenton
A two-dimensional space used to represent surface orientation in terms of its vertical and horizontal components. Thus the plane surface
is represented by the point in gradient space. The steepness of the surface is
and the direction of the slope is . Such a representation does not make explicit the spatial location or extent of surface planes. Convex and concave edges and curvatures will be represented by lines in the gradient space, in the case of planar surface discontinuity edges these will be perpendicular to the edge in the image space, with order along the line determined by the convexity/concavity.
- Draper, S.W., The use of gradient space and dual space in line drawing interpretation
Artificial Intelligence 17 (1981), 461--508.