The 3DTvs project is dedicated to the study of description techniques for the contents, automatic indexing, searches, and browsing in three-dimensional audiovisual contents available on both mobile and stationary platforms. The objective of this project is to improve the performance of the analyses carried out on the three- dimensional formation of audio and video signals. The project also aims to expand audio/video indexing through the multimodality of the approaches. The role of IRCAM in this project focuses on the analysis methods for spatialized audio signals (multi-channel audio streams) in order to improve indexing and provide the localization of sound sources in three-dimensional space.