Object detection and tracking using an EM-based motion estimation and segmentation framework

This paper addresses the segmentation and subsequent tracking of the moving objects within a video sequence. The approach is to jointly produce segmentations and motion parameters which minimise the interframe coding rate of the video sequence. This minimisation is performed using a previously proposed framework based on the expectation-maximisation (EM) algorithm and the minimum description length (MDL) estimate. The paper concentrates on extensions of this framework which have been incorporated to ensure spatial and temporal coherence in the output segmentation sequence. The work has been conducted considering video coding applications and in particular, the MPEG-4 standardisation effort.