Evaluation of bandwidth performance for interactive spherical Video

Spherical Video is nowadays popular, in particular for interactive on-line entertainment multimedia applications such as Google Street View, as well as for Geographical Information Systems (GIS), video surveillance applications, etc. The user is able to explore and navigate audio/visual scenes by freely choosing viewpoint and viewing direction. Spherical Video is typically represented as a classical 2D rectangular panorama video that is then mapped on a sphere mesh and finally rendered on the user´s screen. Existing transmission models of spherical video encode the full panorama video with uniform quality while the sphere mesh is kept implicit. However, in general, the user only watches a restricted field-of-view of the spherical content, which can be interactively modified with pan-tilt-zoom commands. In this paper we evaluate the relevance and optimality of a personalized transmission where the panorama video is decomposed into tiles, which are transmitted at a quality modulated in the spherical regions depending on their likelihood to be visualized from the user interactions.