Abstract
Hough transform (HT) is one of the important methods for detecting or recognizing lines from the edge points in the image. In order to put HT faster, it is promising to decrease the computation costs both in the trigonometric function that forms the basic computational unit and in multiplication. From this view point, Koshimizu et al. proposed a method “Fast Incremental Hough Transform 2 (FIHT2)” that enables one point to be generated on the curve by a single operation of multiplication. However, it has a problem that a significant approximation error occurs. With this shortcoming taken into consideration, this paper proposes a new method “FIHT3” that generates an exact Hough curve using a STTR (Sine-Three-Term-Recurrence). As with FIHT2, FIHT3 method is implemented by a single operation of multiplication for generating one point of Hough curve. Furthermore, it was known experimentally that the FIHT3 method provides the complete accuracy and the fastest computation among any other methods that employ the conventional simultaneous recurrence formula. Moreover, the high-speed algorithm which uses shift operation instead of multiplication was also shown in this paper.
