Light field displays provide a natural sense of 3D visual experience through the glasses-free visualization of the content. It is enabled by the smoothness of the horizontal motion parallax, which is determined by the density of source images allocated to a given field of view. This measure is commonly known as angular resolution, and similarly to spatial resolution, has a fundamental effect on the visual experience. In this paper, we investigate how the reduction of angular and spatial resolution affect each other. Our hypothesis is that lowering spatial resolution to a certain extent does not degrade the perception of the parallax effect, in fact, it may improve it. We carried out a series of subjective tests on a real light field display to test this hypothesis, results of which are introduced in this paper.

Abstract-Light field visualization has progressed and developed significantly in the past years. At the time of this paper, light field displays are utilized in the industry and they are commercially available as well. Although their appearance on the consumer market is approaching, many potential applications of light field technology have not yet been addressed, such as video streaming. In this paper, we present our research on the dynamic adaptive streaming of light field video. In order to evaluate the presented concept of quality switching, we carried out a series of subjective tests, where test participants were shown light field videos containing stallings and switches in spatial and angular resolution.

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The Host Identity Protocol (HIP) is a rather new concept that separates the identity and location information both represented by IP addresses in the current Internet architecture. HIP also has capabilities and efficient extensions to serve macromobility, but it shows unnecessary signaling overhead and handoff latency, when used in micromobility environments. This paper introduces a new method how HIP can be extended to serve as a micromobility protocol.

At the time of this paper, research on the quality of lightfield visualization is continuously gaining momentum, as the excellence in visual performance shall be one of the key enablers of the emergence and long-term presence of this technology on the consumer market. Experiments on perceived quality began in parallel with the appearance of commercially available light-field displays. As the techniques of subjective quality assessment on these displays are not standardized yet, certain parameters may greatly vary, such as viewing conditions. Although most of the current research efforts in this area address forms of static visualization, light-field video is also an essential target of quality evaluation. In this paper, we introduce the results of an experiment investigating the viewing conditions of light-field video quality assessment. The tests directly compare the perceived horizontal motion parallax of static viewing positions with motion patterns. The visual quality of the test conditions was degraded by the reduction of content spatial and angular resolution, as they both affect the smoothness of the horizontal motion parallax.

The rapid growth of IP-based mobile telecommunication technologies in the past few years has revealed situations where not only a single node but an entire network moves and changes its point of attachment to the Internet. The main goal of any protocol supporting network mobility is to provide continuous, optimal and secure Internet access to all nodes and even recursively nested mobile subnetworks inside a moving network. For this purpose, the IETF (Internet Engineering Task Force) has developed the NEtwork MObility Basic Support (NEMO BS) protocol which extends the operation of Mobile IPv6 (MIPv6). In order to bypass the same problems suffered by MIPv6 and NEMO BS, a novel Host Identity Protocol (HIP) extension called HIP-NEMO is introduced, proposed and evaluated in this paper. Our proposal is based on hierarchical topology of mobile RVSs (mRVS), signaling delegation and inter-mRVS communication to enable secure and efficient network mobility support in the HIP layer. The method provides secure connectivity and reachability for every node and nested subnet in the moving network and supports multihomed scenarios as well. Moreover, HIPNEMO reduces signaling and packet overhead during network mobility management by achieving route optimization inside any moving network even in nested scenarios. To evaluate the proposed scheme we present a simulation model implemented in OMNeT++ and discuss the results of our simulation based analysis to show the efficiency of the approach compared to the NEMO BS protocol formulated by the IETF.

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In this paper, we present the concept, the implementation, and the evaluation of our novel angularly continuous light-field format. We compared the subjective visual performance of our format with the perspective camera format through a series of subjective and objective tests. In our extensive subjective study, we used multiple absolute and comparative rating scales and various visual stimuli with different contents and angular resolutions. The perceived quality was assessed by a total of 36 test participants, who were separated based on their scientific expertise. The objective quality was evaluated through the degradations caused by three well-known compression methods. The obtained results indicate that our light-field format may outperform the conventional format, and it generally can provide at least equivalent visual quality. Furthermore, these findings open the way for data size optimization, without compromising the achieved level of perceived quality.