Rotation Detection using the Curl Equation

Rotational types of motion can often be seen in video sequences. However, not a lot of research has been done to investigate rotational motion models for use in video. Analysing this unique type of motion could be very useful. For example, if the the centre of rotation of a spinning object can be efficiently identified, extraction and tracking of it can be made easier by grouping points moving at the same radial speed. It could also improve compression by recording rotation variables. In this paper, we introduce a method for finding the centre of rotation of a rotating object and a basic approach for modelling the rotation for improved image quality. The method requires an initial block based translational motion field.