Digital or analog Hough Transform?

A variation of the Hough Transform that is aimed at detecting digital lines has been recently suggested. Other Hough algorithms are intended to detect straight lines in the analog pre-image. These approaches arc analyzed and compared in terms of the relation between the achievable resolution and the required number of accumulators, using a definition of resolution that is based on the Geometric Probability measure of straight lines. It is shown that the "analog" approach is greatly superior in high resolution applications, where a "digital" Hough Transform would generally require an infeasibly large number of accumulators.