He currently holds a VICI Award (for research excellence) from the Dutch Organisation for Scientific Research. His main research interests are in the fundamentals of content-based image retrieval, color image processing, and computer vision, specifically in the theoretical foundation of geometric and photometric invariants. He is the chair for various conferences and is an associate editor for the IEEE Transactions on Image Processing. Further, he is a program committee member for a number of conferences and an invited speaker at major conferences. He is a lecturer, delivering postdoctoral courses given at various major conferences (CVPR, ICPR, SPIE, and CGIV). He is a member of the IEEE.