Averaging Aircraft Runway Approach Paths

Aircraft do not follow the same route each ight so an accurate analysis of the underlying areas aaected by noise cannot be achieved by considering individual aircraft tracks. This paper describes a method for combining multiple images of aircraft tracks to obtain anàverage' ight path using the Distance Transform as a pre-processing step. The procedures used to average the images of aircraft tracks include computing the distance transform of the input images (using various neighbourhoods of distance values), combining the distance transformed images via the pixelwise median and then thresholding at a suitable value to produce a nal binary image. If the thresholding does not take place, then the nal grey-scale image might be used to give an idea of the degree to which an underlying area will be aaected by aircraft noise.