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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.

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.

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.

We describe an intelligent video categorization engine (IVCE) that uses the learning capability of artificial neural networks (ANNs) to classify suitably preprocessed video segments into a predefined number of semantically meaningful events (categories).

We provide a survey of existing techniques that have been proposed, either directly or indirectly, towards achieving intelligent video categorization. We also compare the performance of two popular ANNs: Kohonen's self‐organizing map (SOM) and fuzzy adaptive resonance theory (Fuzzy ART). In particular, the ANNs are trained offline to form the necessary knowledge base prior to online categorization.

Experimental results show that accurate categorization can be achieved near instantaneously.

The main limitation of this research is the need for a finite set of predefined categories. Further research should focus on generalization of such techniques.

Machine understanding of video footage has tremendous potential for three reasons. First, it enables interactive broadcast of video. Second, it allows unequal error protection for different video shots/segments during transmission to make better use of limited channel resources. Third, it provides intuitive indexing and retrieval for video‐on‐demand applications.

The Video Quality Metric (VQM) is one of the most used objective methods to assess video quality, because of its high correlation with the human visual system (HVS). VQM is, however, not viable in real-time deployments such as mobile streaming, not only due to its high computational demands but also because, as a Full Reference (FR) metric, it requires both the original video and its impaired counterpart. In contrast, No Reference (NR) objective algorithms operate directly on the impaired video and are considerably faster but loose out in accuracy. The purpose of this paper is to study how differently NR metrics perform in the presence of network impairments.

The authors assess eight NR metrics, alongside a lightweight FR metric, using VQM as benchmark in a self-developed network-impaired video data set. This paper covers a range of methods, a diverse set of video types and encoding conditions and a variety of network impairment test-cases.

The authors show the extent by which packet loss affects different video types, correlating the accuracy of NR metrics to the FR benchmark. This paper helps identifying the conditions under which simple metrics may be used effectively and indicates an avenue to control the quality of streaming systems.

Most studies in literature have focused on assessing streams that are either unaffected by the network (e.g. looking at the effects of video compression algorithms) or are affected by synthetic network impairments (i.e. via simulated network conditions). The authors show that when streams are affected by real network conditions, assessing Quality of Experience becomes even harder, as the existing metrics perform poorly.