The advent of affordable 3D capture and display hardware is making volumetric videoconferencing feasible. This technology increases the immersion of the participants, breaking the flat restriction of 2D screens, by allowing them to collaborate and interact in shared virtual reality spaces. In this paper we introduce the design and development of an architecture intended for volumetric videoconferencing that provides a highly realistic 3D representation of the participants, based on pointclouds. A pointcloud representation is suitable for real-time applications like video conferencing, due to its low-complexity and because it does not need a time consuming reconstruction process. As transport protocol we selected low latency DASH, due to its popularity and client-based adaptation mechanisms for tiling. This paper presents the architectural design, details the implementation, and provides some referential results. The demo will showcase the system in action, enabling volumetric videoconferencing using pointclouds.

Existing broadcast networks can deliver identical content to a large number of users. Broadband networks can deliver personalized content to specific users. Hybrid delivery tries to use the best of both types of networks to provide customized services to many users. This paper studies the theoretical aspects and challenges behind the delivery of multimedia content over hybrid broadcast broadband networks, including bootstrapping, synchronization and resynchronization. It presents a solution based on the use of a global clock which does not require communication across networks and is compatible with existing technologies. This solution is implemented in a multimedia player and evaluated against two real-world scenarios, mixing DVB or FM broadcast networks with a broadband IP network. The results confirm the theoretical approach and show that some fine tuning in the networks is needed for a tighter synchronization.

Multimedia applications are challenging software and require collaboration of very different components such as networking, rendering, or scripting to provide a nice user experience. GPAC is an open source multimedia framework that implements a vast number of components and helps experimenting with different types of multimedia applications. It provides a multimedia packager, some servers and a player for dynamic and interactive multimedia content. In this paper, we present the recent additions to the project which allow experimenting with new applications such as dynamic home networking or rich broadcasting of interactive content on the latest devices, including with 3D displays. Such experiments can be useful in research work and, as illustrated, in academic environment for educational purposes.

In recent years, audio-visual distribution over Internet has witnessed the growing usage of HTTP based delivery systems. While these systems have their drawbacks for some use-cases, they also have many advantages, the most important one being reusing the existing delivery infrastructure such as HTTP servers, proxies and caches. The MPEG group has started the standardization of the Dynamic Adaptive Streaming over HTTP (DASH) of major transport formats, MPEG-2 TS and ISO Base Media File, and mostly focuses on audio, video and subtitle formats. We believe Rich Media services have a role to play in this landscape, as a presentation layer for the audio-visual content first, but also as a dedicated media in the DASH content for real-time media-synchronized interactive services. In this paper, we present a study on usages of DASH for Rich Media Services.