Hough transform

The Hough transform (HT) is a mathematical technique in image processing to discern lines and their direction, a step in the automated/computer identification/interpretation of image data. The Hough transform was first described by Paul Hough in 1959, which he developed to analyze photos in bubble chambers (a type of 1950s particle accelerator sensor). Variants have been developed, e.g., to detect circles and other shapes. A variant, the rolling Hough transform (RHT), which applies it to small regions of an extensive image to identify local linear patterns, was developed for astrophysical analysis of HI maps.