Algorithms for ultra-fast location of ellipses in digital images

This paper shows how an earlier sampling approach can be extended by a range of techniques related to our triple bisection algorithm. These techniques are characterised by very high speed of operation coupled with accurate location: a suitable technique can be chosen and tuned for any of a number of scenarios where a specific level of robustness is required. While we have tested these techniques on images in which the ellipses are cereal grains with close to 2:1 aspect ratio, they appear to be suitable for locating ellipses of any eccentricity with near the ultimate speed of processing.