My research focuses on search engines and retrieval systems that provide users with intelligent access to multimedia content. I am a senior researcher in the Delft Multimedia Information Retrieval Lab.

My expertise lies in speech and language technologies and how meaning is expressed in human language. Much of my research has concentrated on methods for automatically structuring audio and for indexing audio using speech recognition techniques. Recently, my work has focused increasingly on multimedia in social networks and on human computation, including crowdsourcing.