\section{Thesis outline}

First, in Chapter~\ref{f}, we give some preliminary information required to understand the types of objects we are manipulating in this thesis.
We then proceed to compare 3D and video content: video and 3D share many features, and analyzing video setting gives inspiration for building a 3D streaming system.

In Chapter~\ref{sote}, we present a review of the state of the art in multimedia interaction and streaming.
This chapter starts with an analysis of the video streaming standards.
Then it reviews the different 3D streaming approaches.
The last section of this chapter focuses on 3D interaction.

Then, in Chapter~\ref{bi}, we present our first contribution: an in-depth analysis of the impact of the UI on navigation and streaming in a 3D scene.
We first develop a basic interface for navigating in 3D and then, we introduce 3D objects called \emph{bookmarks} that help users navigating in the scene.
We then present a user study that we conducted on 51 people which shows that bookmarks ease user navigation: they improve performance at tasks such as finding objects.
% Then, we setup a basic 3D streaming system that allows us to replay the traces collected during the user study and simulate 3D streaming at the same time.
We analyze how the presence of bookmarks impacts the streaming: we propose and evaluate streaming policies based on precomputations relying on bookmarks and that measurably increase the quality of experience.

In Chapter~\ref{d3}, we present the most important contribution of this thesis: DASH-3D.
DASH-3D is an adaptation of DASH (Dynamic Adaptive Streaming over HTTP): the video streaming standard, to 3D streaming.
We first describe how we adapt the concepts of DASH to 3D content, including the segmentation of content.
We then define utility metrics that rate each chunk depending on the user's position.
Then, we present a client and various streaming policies based on our utilities which can benefit from DASH format.
We finally evaluate the different parameters of our client.

In Chapter~\ref{sb}, we present our last contribution: the integration of the interaction ideas that we developed in Chapter~\ref{bi} into DASH-3D.
We first develop an interface that allows desktop as well as mobile devices to navigate in streamed 3D scenes, and that introduces a new style of bookmarks.
We then explain why simply applying the ideas developed in Chapter~\ref{bi} is not sufficient and we propose more efficient precomputations that enhance the streaming.
Finally, we present a user study that provides us with traces on which we evaluate the impact of our extension of DASH-3D on the quality of service and on the quality of experience.
