Influence of discretization in image space on Hough transform

摘要

The manner by which the short line segments are connected to approximate the ideal straight line in digital image space will influence the performance of Hough transform. The peak spreading can be avoided when Δρ satisfies a certain condition. Consequently, a new approach called a variable-Δρ Hough transform having Δρ as a function of θ is proposed. For the probabilistic Hough transforms (PHT) it is shown that although one of their advantages is the ability to avoid direct quantization of parameter space but the influence of the discretization in image space becomes more serious. To avoid this problem, a suitable tolerance parameter δ as a function of ρ and θ is required.