Smooth region structure: folds, domes, bowls, ridges, valleys and slopes.

This paper shows that the structure of the isobrightness contours in 'smooth' regions of a segmented image may be used to quantify the variation ill shading. Topographic terms are then appropriate for labelling the X-inds of generic structure! that arise in smooth regions, domes, bowls, ridges, valleys, slopes and folds are quantifiable. The method uses contour context rather than filfer banks or a solution to the shape from shading problem to quantify the form of a region's brightness function. Region segmentation (distinguishing smooth from textured regions) is also performed with a largely filter free segmentation scheme with an brief outline of the scheme being given.