His research is in the area of Machine Learning and Computer Vision with applications in Multimedia Analysis and Multimodal Human Machine Interaction. This includes low level analysis as well as learning from large datasets or from user interaction. He is particularly interested in the problems of Motion Analysis (including tracking and motion estimation), (semantic) Object Segmentation and (Human) Action Recognition (including face and gesture analysis). A recent line of activity involves multimodal human sensing for Brain Computer Interfaces. He is an associate editor of the Image and Vision Computing Journal and of the journal of Multimedia, the general chair of the 10th Int’l Workshop of Image Analysis for Multimedia Interactive Services and in the organisation committee of a number of conferences and workshops.