SCALE-IMPRECISION SPACE

It is argued that image measurements should satisfy two requirements o f physical plausibility: the measurements are of non-zero scale and no n-zero imprecision; and two required invariances, nothing is lost by e xpanding the image and nothing is lost by increasing the contrast of t he image. A model of measurements satisfying these constraints, based on blurring the graph of the incident luminance, is described. Within this framework, several types of filtering can be expressed: mean filt ering (ordinary scale space); median filtering: and mode filtering. It is found that of these possibilities, a system based on mode filterin g produces interesting results. In particular, edges-defined as discon tinuities-naturally appear, and their behaviour over scale and impreci sion is presented.