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The first purpose of this paper is to propose a scalable video coding scheme providing flexibility in video transmission, especially under wireless environment. The second purpose is to analyze the problem of lengthening the key frame interval in distributed video coding (DVC), and propose an approach to improve the rate‐distortion (RD) performance of DVC for long group‐of‐frames (GOF) size.

In the proposed scheme, a base layer is first obtained from an H.264 coder. When a DVC coder is then used to code the enhancement layer, information in processing the base layer is extracted and analyzed to make multiple side‐information available and reduce error accumulation for DVC coding, thus further improving the performance of the DVC coder.

By dividing video into base and enhancement layers, the combined video coding architecture enables a flexible video transmission. In addition, several methods are used to improve the RD performance in DVC coding. Simulation shows that the proposed scheme outperforms non‐scalable DVC for long GOF size.

Prediction from the decoding loop in base layer encoder largely reduces enhancement layer spatial redundancy. Multiple side‐information provides better estimation for DVC reconstruction. Long prediction loop is more reliable because error accumulation is effectively compensated.

The interdisciplinary nature of video networking, coupled with various recent developments in standards, proposals and applications, poses great challenges to the research and industrial communities working in this area. The main purpose of this paper is to provide a tutorial and survey on recent advances in video networking from an integrated perspective of both video signal processing and networking.

Detailed technical descriptions and insightful analysis are presented for recent and emerging video coding standards, in particular the H.264 family. The applications of selected video coding standards in emerging wireless networks are then introduced with an emphasis on scalable video streaming in multihomed mobile networks. Both research challenges and potential solutions are discussed along the description, and numerical results through simulations or experiments are provided to reveal the performances of selected coding standards and networking algorithms.

The tutorial helps to clarify the similarities and differences among the considered standards and networking applications. A number of research trends and challenges are identified, and selected promising solutions are discussed. This practice would provoke further thoughts on the development of this area and open up more research and application opportunities.

Not all the concerned video coding standards are complemented with thorough studies of networking application scenarios.

The discussed video coding standards are either playing or going to play indispensable roles in the video industry; the introduced networking scenarios bring together these standards and various emerging wireless networking paradigms towards innovative application scenarios.

The comprehensive overview and critiques on existing standards and application approaches offer a valuable reference for researchers and system developers in related research and industrial communities.

The purpose of this paper is to provide a tutorial and survey on recent advances in multimedia networking from an integrated perspective of both video networking and building digital video libraries. The nature of video networking, coupled with various recent developments in standards, proposals and applications, poses great challenges to the research and industrial communities working in this area.

This paper presents an insightful analysis for recent and emerging multimedia applications in digital video libraries and on video coding standards and their applications in digital libraries. Emphasis is given on those standards and mechanisms that enable multimedia content adaptation fully interoperable according to the vision of Universal Multimedia Access vision.

The tutorial helps elucidate the similarities and differences among the considered standards and networking applications. A number of research trends and challenges are identified, and selected promising solutions are discussed. This practice would needle further thoughts on the development of this area and open-up more research and application opportunities.

The paper does not provide methodical studies of networking application scenarios for all the discussed video coding standards and Quality of Service (QoS) management mechanisms.

The paper provides an overview of which technologies/mechanisms are being used broadly in networking scenarios of digital video libraries. The discussed networking scenarios bring together video coding standards and various emerging wireless networking paradigms toward innovative application scenarios.

QoS mechanisms and video coding standards that support multimedia applications for digital video libraries need to become well-known by library managers and professional associations in the fields of libraries and archives. The comprehensive overview and critiques on existing standards and application approaches offer a valuable reference for researchers and system developers in related research and industrial communities.

High-efficiency video coding (HEVC) is the latest video coding standard that has better coding efficiency than the H.264/advanced video coding (AVC) standard. The purpose of this paper is to design and develop an effective block search mechanism for the video compression-HEVC standard such that the developed compression standard is applied for the communication applications.

In the proposed method, an rate-distortion (RD) trade-off, named regressive RD trade-off is used based on the conditional autoregressive value at risk (CaViar) model. The motion estimation (ME) is based on the new block search mechanism, which is developed with the modification in the Ordered Tree-based Hex-Octagon (OrTHO)-search algorithm along with the chronological Salp swarm algorithm (SSA) based on deep recurrent neural network (deepRNN) for optimally deciding the shape of search, search length of the tree and dimension. The chronological SSA is developed by integrating the chronological concept in SSA, which is used for training the deep RNN for ME.

The competing methods used for the comparative analysis of the proposed OrTHO-search based RD + chronological-salp swarm algorithm (RD + C-SSA) based deep RNN are support vector machine (SVM), fast encoding framework, wavefront-based high parallel (WHP) and OrTHO-search based RD method. The proposed video compression method obtained a maximum peak signal-to-noise ratio (PSNR) of 42.9180 dB and a maximum structural similarity index measure (SSIM) of 0.9827.

In this research, an effective block search mechanism was developed with the modification in the OrTHO-search algorithm along with the chronological SSA based on deepRNN for the video compression-HEVC standard.

The purpose of this study is to examine the effect of craftsmanship content and social distance embedded in the craftsmanship content on luxury brand experiences, perceived luxury and brand purchase intentions using a social media video.

The authors conducted a single factor (close social distance vs great social distance vs control group) using a between-subjects experimental design. The social distance was manipulated by the presence (i.e. a close social distance) or absence (i.e. a great social distance) of a consumer scene in a craftsmanship video shown on social media. The control group watched a video with non-craftsmanship content. Then, brand experience, perceived luxury and purchase intentions were measured.

The results showed that the control group perceived less luxury and had lower brand experiences and purchase intentions than the group that watched the video without a consumer scene. In addition, participants who watched the craftsmanship video that included a consumer scene (i.e. a close social distance) had stronger brand experiences than those who watched the video without the scene (i.e. a great social distance). The brand experience increased perceived luxury and purchase intentions.

By manipulating social distance and providing better brand experiences in social media, experiential marketing allows luxury brands to reconcile two apparently incompatible goals: maintaining an exclusive image while increasing purchase intentions.

Streaming audio/video contents over the Internet requires large network bandwidth and timely delivery of media data. A streaming session is generally long and also needs a large I/O bandwidth at the streaming server. A streaming server, however, has limited network and I/O bandwidth. For this reason, a streaming server alone cannot scale a streaming service well. An entire audio/video media file often cannot be cached due to intellectual property right concerns of the content owners, security reasons, and also due to its large size. This makes a streaming service hard to scale using conventional proxy servers. Media file compression using variable‐bit‐rate (VBR) encoding is necessary to get constant quality video playback although it produces traffic bursts. Traffic bursts either waste network bandwidth or cause hiccups in the playback. Large network latency and jitter also cause long start‐up delay and unwanted pauses in the playback, respectively. In this paper, we propose a proxy based constant‐bit‐rate (CBR)‐transmission scheme for VBR‐encoded videos and a scalable streaming scheme that uses a CBRtransmission scheme to stream stored videos over the Internet. Our CBR‐streaming scheme allows a server to transmit a VBRencoded video at a constant bit rate, close to its mean encoding bit rate, and deals with the network latency and jitter issues efficiently in order to provide quick and hiccup free playback without caching an entire media file. Our scalable streaming scheme also allows many clients to share a server stream. We use prefix buffers at the proxy to cache the prefixes of popular videos, to minimize the start‐up delay and to enable near mean bit rate streaming from the server as well as from the proxy. We use smoothing buffers at the proxy not only to eliminate jitter and traffic burst effects but also to enable many clients to share the same server stream. We present simulation results to demonstrate the effectiveness of our streaming scheme.

Technological developments and new customer expectations of immediacy have driven businesses to adopt on-demand service models. The purpose of this paper is to study the characteristics of a range of on-demand services in order to better understand the meaning of “on-demand” and its implications for service management. This enables the on-demand service logic to be applied to other service contexts, where it may add value for customers.

The study starts with a focused literature review and continues with a multiple case study methodology, as the on-demand service concept is in the early stages of theory development. Seven cases were studied, based on a maximum variation sampling strategy.

The results show that on-demand services are characterized by three interrelated characteristics: being highly available, responsive and scalable. Analysis further reveals that on-demand services display differences within the conceptual boundaries of these characteristics, i.e. they vary in terms of their availability, responsiveness and scalability.

Drawing on these findings, the study contributes to the service literature by being the first to specifically conceptualize and define the on-demand services concept and reveal three key characteristics that clarify the distinctive nature of this service type. Accordingly, on-demand services are clearly differentiated from other services. Additionally, the paper discusses the variety within on-demand services and develops an on-demand service continuum that gives detailed insights into the conceptual variations within such services.

Transmitting video over user datagram protocol (UDP) has been considered advantageous because it allows for discarding of packets in favor of retransmissions, and sender‐controlled timing. Using UDP has been criticized because it allows video streams to consume more than their fair share of bandwidth, which is typically associated with the back‐off behavior of transmission control protocol (TCP). TCP‐friendly algorithms are meant as a middle path. However, UDP delivery to end systems may still be prevented by firewalls or for other reasons, and TCP must be used. This in turn suffers from bandwidth fluctuations. Investigates an architecture that separates the transfer of a video stream over long distances. Considers a proxy server to translate the traffic and two straightforward approaches for the translation of a layered video stream transmission from the TCP‐friendly transport protocol to TCP. Does not expect that one of these two approaches is by itself suited for the task, but investigating them will provide insights into their basic functions and help in discovering appropriate modifications. For the investigation, an experimental approach was used where network behavior and content are emulated.

Light field images (LFIs) have gained popularity as a technology to increase the field of view (FoV) of plenoptic cameras since they can capture information about light rays with a large FoV. Wide FoV causes light field (LF) data to increase rapidly, which restricts the use of LF imaging in image processing, visual analysis and user interface. Effective LFI coding methods become of paramount importance. This paper aims to eliminate more redundancy by exploring sparsity and correlation in the angular domain of LFIs, as well as mitigate the loss of perceptual quality of LFIs caused by encoding.

This work proposes a new efficient LF coding framework. On the coding side, a new sampling scheme and a hierarchical prediction structure are used to eliminate redundancy in the LFI's angular and spatial domains. At the decoding side, high-quality dense LF is reconstructed using a view synthesis method based on the residual channel attention network (RCAN).

In three different LF datasets, our proposed coding framework not only reduces the transmitted bit rate but also maintains a higher view quality than the current more advanced methods.

(1) A new sampling scheme is designed to synthesize high-quality LFIs while better ensuring LF angular domain sparsity. (2) To further eliminate redundancy in the spatial domain, new ranking schemes and hierarchical prediction structures are designed. (3) A synthetic network based on RCAN and a novel loss function is designed to mitigate the perceptual quality loss due to the coding process.

This study investigates how debrief conversations unfold during virtual coaching sessions that provide embedded opportunities to practice teaching within a mixed reality simulation (MRS). We examine how teacher and coach topical episodes function (agreeing, explaining, clarifying, probing, recapping, reflecting and suggesting) to activate reflection as part of virtual coaching.

Grounded in Vygotsky's sociocultural theory and the belief that learning is collaborative and impacts how pre- and in-service teachers construct knowledge, this exploratory case study draws on insights from 15 graduate students (5 pre-service teachers (PSTs) and 10 in-service teachers (ISTs)) who participated in virtual coaching with embedded practice opportunities. Data sources were video recordings and transcripts of 15 virtual coaching sessions, and one-on-one postcoaching interviews. Coding categories were determined through the constant comparative analysis method.

Findings indicate that an MRS provides an immediate context for reflection, which guided the debrief conversations. Additionally, functions occurred with varying frequency among PSTs and ISTs, and across both groups, probing questions often led directly to reflecting and recapping the shared simulation context.

This study had a small sample (n = 15) and the use of an MRS, while widely used, is not necessarily a scalable practice.

In times of remote teaching, like during corona virus 2019 (COVID-19), opportunities to simulate clinical experiences become vital. With a limited research base, learning how teachers engage with and learn from simulated experiences is a key to creating rich learning opportunities for teachers.