The Hough transform is a well-established scheme for detecting digital line components

in a binary edge image. A key to its success in practice is the notion of voting on an

accumulator array in the parameter plane. This paper discusses computational limitation

of such voting-based schema under the constraint that all possible line components in a

given image must be reported. Various improvements are presented based on algorithmic

techniques and data structures. New schema with less computation time and working space

based on totally dierent ideas are also proposed with some experimental results.