269 research outputs found
Subjective assessment of super multiview video with coding artifacts
The subjective assessment of super multiview (SMV) video considers two main perceptual factors: image quality and visual comfort at the viewpoint transition. While previous works only covered raw content with high levels of visual comfort, this work supersedes them by targeting the subjective assessment of SMV content with coding artifacts. The outcome of this analysis yields important conclusions regarding the relationship between these two factors, indicating that 1) the perceived image quality is independent from the view point change speed, and 2) the perceived visual comfort at the view point transition is independent from the image quality. These conclusions facilitate the extension of the scope of existing subjective perception models, designed for raw SMV content, to coded content
Depth map compression via 3D region-based representation
In 3D video, view synthesis is used to create new virtual views between
encoded camera views. Errors in the coding of the depth maps introduce
geometry inconsistencies in synthesized views. In this paper, a new 3D plane
representation of the scene is presented which improves the performance of
current standard video codecs in the view synthesis domain. Two image segmentation
algorithms are proposed for generating a color and depth segmentation.
Using both partitions, depth maps are segmented into regions without
sharp discontinuities without having to explicitly signal all depth edges. The
resulting regions are represented using a planar model in the 3D world scene.
This 3D representation allows an efficient encoding while preserving the 3D
characteristics of the scene. The 3D planes open up the possibility to code
multiview images with a unique representation.Postprint (author's final draft
New visual coding exploration in MPEG: Super-MultiView and free navigation in free viewpoint TV
ISO/IEC MPEG and ITU-T VCEG have recently jointly issued
a new multiview video compression standard, called 3D-HEVC,
which reaches unpreceded compression performances for linear,dense camera arrangements. In view of supporting future highquality,auto-stereoscopic 3D displays and Free Navigation virtual/augmented reality applications with sparse, arbitrarily arranged camera setups, innovative depth estimation and virtual view synthesis techniques with global optimizations over all camera views should be developed. Preliminary studies in response to the MPEG-FTV (Free viewpoint TV) Call for Evidence suggest these
targets are within reach, with at least 6% bitrate gains over 3DHEVC
technology
Objective quality metric for 3D virtual views
In free-viewpoint television (FTV) framework, due to hard-ware and bandwidth constraints, only a limited number of viewpoints are generally captured, coded and transmitted; therefore, a large number of views needs to be synthesized at the receiver to grant a really immersive 3D experience. It is thus evident that the estimation of the quality of the synthesized views is of paramount importance. Moreover, quality assessment of the synthesized view is very challeng-ing since the corresponding original views are generally not available either on the encoder (not captured) or the decoder side (not transmitted). To tackle the mentioned issues, this paper presents an algorithm to estimate the quality of the synthesized images in the absence of the corresponding ref-erence images. The algorithm is based upon the cyclopean eye theory. The statistical characteristics of an estimated cy-clopean image are compared with the synthesized image to measure its quality. The prediction accuracy and reliability of the proposed technique are tested on standard video dataset compressed with HEVC showing excellent correlation results with respect to state-of-the-art full reference image and video quality metrics. Index Terms — Quality assessment, depth image based rendering, view synthesis, FTV, HEVC 1
FVV Live: A real-time free-viewpoint video system with consumer electronics hardware
FVV Live is a novel end-to-end free-viewpoint video system, designed for low
cost and real-time operation, based on off-the-shelf components. The system has
been designed to yield high-quality free-viewpoint video using consumer-grade
cameras and hardware, which enables low deployment costs and easy installation
for immersive event-broadcasting or videoconferencing.
The paper describes the architecture of the system, including acquisition and
encoding of multiview plus depth data in several capture servers and virtual
view synthesis on an edge server. All the blocks of the system have been
designed to overcome the limitations imposed by hardware and network, which
impact directly on the accuracy of depth data and thus on the quality of
virtual view synthesis. The design of FVV Live allows for an arbitrary number
of cameras and capture servers, and the results presented in this paper
correspond to an implementation with nine stereo-based depth cameras.
FVV Live presents low motion-to-photon and end-to-end delays, which enables
seamless free-viewpoint navigation and bilateral immersive communications.
Moreover, the visual quality of FVV Live has been assessed through subjective
assessment with satisfactory results, and additional comparative tests show
that it is preferred over state-of-the-art DIBR alternatives
HEVC-based 3D holoscopic video coding using self-similarity compensated prediction
Holoscopic imaging, also known as integral, light field, and plenoptic imaging, is an appealing technology for glassless 3D video systems, which has recently emerged as a prospective candidate for future image and video applications, such as 3D television. However, to successfully introduce 3D holoscopic video applications into the market, adequate coding tools that can efficiently handle 3D holoscopic video are necessary. In this context, this paper discusses the requirements and challenges for 3D holoscopic video coding, and presents an efficient 3D holoscopic coding scheme based on High Efficiency Video Coding (HEVC). The proposed 3D holoscopic codec makes use of the self-similarity (SS) compensated prediction concept to efficiently explore the inherent correlation of the 3D holoscopic content in Intra- and Inter-coded frames, as well as a novel vector prediction scheme to take advantage of the peculiar characteristics of the SS prediction data. Extensive experiments were conducted, and have shown that the proposed solution is able to outperform HEVC as well as other coding solutions proposed in the literature. Moreover, a consistently better performance is also observed for a set of different quality metrics proposed in the literature for 3D holoscopic content, as well as for the visual quality of views synthesized from decompressed 3D holoscopic content.info:eu-repo/semantics/submittedVersio
Quality-aware adaptive delivery of multi-view video
Advances in video coding and networking technologies have
paved the way for the Multi-View Video (MVV) streaming.
However, large amounts of data and dynamic network conditions
result in frequent network congestion, which may prevent
video packets from being delivered on time. As a consequence,
the 3D viewing experience may be degraded signifi-
cantly, unless quality-aware adaptation methods are deployed.
There is no research work to discuss the MVV adaptation of
decision strategy or provide a detailed analysis of a dynamic
network environment. This work addresses the mentioned issues
for MVV streaming over HTTP for emerging multi-view
displays. In this research work, the effect of various adaptations
of decision strategies are evaluated and, as a result, a
new quality-aware adaptation method is designed. The proposed
method is benefiting from layer based video coding in
such a way that high Quality of Experience (QoE) is maintained
in a cost-effective manner. The conducted experimental
results on MVV streaming using the proposed strategy are
showing that the perceptual 3D video quality, under adverse
network conditions, is enhanced significantly as a result of the
proposed quality-aware adaptation
- …