Two enhancements to the probabilistic Hough transform have been proposed, including the use of a new distinctiveness measure for hypothesis testing and a localized parameter vector search guided by evidence clusters. Preliminary experimental results show that large computational saving is achieved by employing the probabilistic Hough transform with distinctiveness measure when compared with the standard Hough transform. Furthermore, the use of evidence cluster can lead to further saving in computation time, especially when the image contains a large number of image points