Robust pan, tilt and zoom estimation

Abstract

We propose a method for estimating the motion parameters for a rotating camera with a possibly changing focal length. This method is suitable for analysing sport event videos. The estimation process consists of three stages: (1) robust estimation of the 2D translational components; (2) 2D block-based motion estimation; (3) robust estimation of a parametric motion model. For more reliability, confidence measures for the 2D motion vectors are introduced. The reliability of the method is illustrated on some difficult real image sequences.