245 research outputs found
Providing 3D video services: the challenge from 2D to 3DTV quality of experience
Recently, three-dimensional (3D) video has decisively burst onto the entertainment industry scene, and has arrived in households even before the standardization process has been completed. 3D television (3DTV) adoption and deployment can be seen as a major leap in television history, similar to previous transitions from black and white (B&W) to color, from analog to digital television (TV), and from standard definition to high definition. In this paper, we analyze current 3D video technology trends in order to define a taxonomy of the availability and possible introduction of 3D-based services. We also propose an audiovisual network services architecture which provides a smooth transition from two-dimensional (2D) to 3DTV in an Internet Protocol (IP)-based scenario. Based on subjective assessment tests, we also analyze those factors which will influence the quality of experience in those 3D video services, focusing on effects of both coding and transmission errors. In addition, examples of the application of the architecture and results of assessment tests are provided
Advanced Free Viewpoint Video Streaming Techniques
Free-viewpoint video is a new type of interactive multimedia service allowing users to control their viewpoint and generate new views of a dynamic scene from any perspective. The uniquely generated and displayed views are composed from two or more high bitrate camera streams that must be delivered to the users depending on their continuously changing perspective. Due to significant network and computational resource requirements, we proposed scalable viewpoint generation and delivery schemes based on multicast forwarding and distributed approach. Our aim was to find the optimal deployment locations of the distributed viewpoint synthesis processes in the network topology by allowing network nodes to act as proxy servers with caching and viewpoint synthesis functionalities. Moreover, a predictive multicast group management scheme was introduced in order to provide all camera views that may be requested in the near future and prevent the viewpoint synthesizer algorithm from remaining without camera streams. The obtained results showed that even 42% traffic decrease can be realized using distributed viewpoint synthesis and the probability of viewpoint synthesis starvation can be also significantly reduced in future free viewpoint video services
Representation and coding of 3D video data
Livrable D4.1 du projet ANR PERSEECe rapport a été réalisé dans le cadre du projet ANR PERSEE (n° ANR-09-BLAN-0170). Exactement il correspond au livrable D4.1 du projet
3D video coding and transmission
The capture, transmission, and display of
3D content has gained a lot of attention in the last few
years. 3D multimedia content is no longer con fined to
cinema theatres but is being transmitted using stereoscopic
video over satellite, shared on Blu-RayTMdisks,
or sent over Internet technologies. Stereoscopic displays
are needed at the receiving end and the viewer needs to
wear special glasses to present the two versions of the
video to the human vision system that then generates
the 3D illusion. To be more e ffective and improve the
immersive experience, more views are acquired from a
larger number of cameras and presented on di fferent displays,
such as autostereoscopic and light field displays.
These multiple views, combined with depth data, also
allow enhanced user experiences and new forms of interaction
with the 3D content from virtual viewpoints.
This type of audiovisual information is represented by a
huge amount of data that needs to be compressed and
transmitted over bandwidth-limited channels. Part of
the COST Action IC1105 \3D Content Creation, Coding
and Transmission over Future Media Networks" (3DConTourNet)
focuses on this research challenge.peer-reviewe
Navigation domain representation for interactive multiview imaging
Enabling users to interactively navigate through different viewpoints of a
static scene is a new interesting functionality in 3D streaming systems. While
it opens exciting perspectives towards rich multimedia applications, it
requires the design of novel representations and coding techniques in order to
solve the new challenges imposed by interactive navigation. Interactivity
clearly brings new design constraints: the encoder is unaware of the exact
decoding process, while the decoder has to reconstruct information from
incomplete subsets of data since the server can generally not transmit images
for all possible viewpoints due to resource constrains. In this paper, we
propose a novel multiview data representation that permits to satisfy bandwidth
and storage constraints in an interactive multiview streaming system. In
particular, we partition the multiview navigation domain into segments, each of
which is described by a reference image and some auxiliary information. The
auxiliary information enables the client to recreate any viewpoint in the
navigation segment via view synthesis. The decoder is then able to navigate
freely in the segment without further data request to the server; it requests
additional data only when it moves to a different segment. We discuss the
benefits of this novel representation in interactive navigation systems and
further propose a method to optimize the partitioning of the navigation domain
into independent segments, under bandwidth and storage constraints.
Experimental results confirm the potential of the proposed representation;
namely, our system leads to similar compression performance as classical
inter-view coding, while it provides the high level of flexibility that is
required for interactive streaming. Hence, our new framework represents a
promising solution for 3D data representation in novel interactive multimedia
services
Image-based compression, prioritized transmission and progressive rendering of circular light fields (CLFS) for ancient Chinese artifacts
This paper proposes an efficient algorithm for the compression, prioritized transmission and progressive rendering of circular light field (CLF) for ancient Chinese artifacts. It employs wavelet coder to achieve spatial scalability and divide the compressed data into a lower resolution base layer and an additional enhancement layer. The enhancement layer is coded as in JPEG2000 into packets where the base-layer is coded using disparity compensation prediction (DCP). The frame structure is designed to provide efficient access to the compressed data in order to support selective transmission and decoding. The depth and alpha maps are coded analogously. A prioritized transmission scheme which support interactive progressive rendering is also proposed to further reduce the latency and response time of rendering. © 2010 IEEE.published_or_final_versionThe 2010 IEEE Asia Pacific Conference on Circuits and Systems (APCCAS), Kuala Lumpur Malaysia, 6-9 December 2010. In IEEE APCCAS Proceedings, 2010, p. 340-34
DĂŒnaamiline kiiruse jaotamine interaktiivses mitmevaatelises video vaatevahetuse ennustamineses
In Interactive Multi-View Video (IMVV), the video has been captured by numbers of
cameras positioned in array and transmitted those camera views to users. The user can
interact with the transmitted video content by choosing viewpoints (views from different
cameras in the array) with the expectation of minimum transmission delay while
changing among various views. View switching delay is one of the primary concern that
is dealt in this thesis work, where the contribution is to minimize the transmission delay
of new view switch frame through a novel process of selection of the predicted view
and compression considering the transmission efficiency. Mainly considered a realtime
IMVV streaming, and the view switch is mapped as discrete Markov chain, where
the transition probability is derived using Zipf distribution, which provides information
regarding view switch prediction. To eliminate Round-Trip Time (RTT) transmission
delay, Quantization Parameters (QP) are adaptively allocated to the remaining redundant
transmitted frames to maintain view switching time minimum, trading off with
the quality of the video till RTT time-span. The experimental results of the proposed
method show superior performance on PSNR and view switching delay for better viewing quality over the existing methods
A modified multiview video streaming system using 3-tier architecture
In this paper, we present a modified inter-view prediction Multiview Video Coding (MVC) scheme from the perspective of viewer's interactivity. When a viewer requests some view(s), our scheme leads to lower transmission bit-rate. We develop an interactive multiview video streaming system exploiting that modified MVC scheme. Conventional interactive multiview video systems require high bandwidth due to redundant data being transferred. With real data test sequences, clear improvements are shown using the proposed interactive multiview video system compared to competing ones in terms of the average transmission bit-rate and storage size of the decoded (i.e., transferred) data with comparable rate-distortion
- âŠ