Localisation for Augmented Reality at Sports Events

The use of computer generated graphics and visualisations has become increasingly common in professional sports broadcasting over the past two decades. Overlaid graphics are designed to convey information about the game to the spectator in a way that is contextualised spatially, such as virtual offside lines being overlaid on soccer footage. We aim to take these graphics, that are only seen in professional broadcasting, and provide them to on-site sports spectators using an augmented reality mobile application. Allowing fans in the stadium to view the same pitch-aligned visualisations as those watching at home, all rendered on their phone in real time. In sports broadcasting the alignment of these graphics with the environment is often achieved by using professional cameras equipped with high accuracy sensors or elaborate manual calibration techniques to measure the broadcasting camera's position and orientation. These measurements allow the graphics to be accurately matched to the camera view. The goal of our research was to design a method of camera localisation that will allow spectators to enjoy accurately aligned augmented reality content with minimal prior calibration and without a complicated manual initialisation process. We investigated whether line pitch markings could be used to estimate an on-site user's position and orientation with sufficient accuracy to align augmented reality visualisations with the pitch. Our evaluation found that our approach performed with sufficient speed and accuracy to form the basis of a mobile augmented reality application for on-site spectators