14,968 research outputs found
Can small be beautiful? assessing image resolution requirements for mobile TV
Mobile TV services are now being offered in several countries, but for cost reasons, most of these services offer material directly recoded for mobile consumption (i.e. without additional editing). The experiment reported in this paper, aims to assess the image resolution and bitrate requirements for displaying this type of material on mobile devices. The study, with 128 participants, examined responses to four different image resolutions, seven video encoding bitrates, two audio bitrates and four content types. The results show that acceptability is significantly lower for images smaller than 168×126, regardless of content type. The effect is more pronounced when bandwidth is abundant, and is due to important detail being lost in the smaller screens. In contrast to previous studies, participants are more likely to rate image quality as unacceptable when the audio quality is high
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Open-standards rich media mobile platform & rapid deployment service creation tool
This paper builds upon the work carried out by Brunel University in the field of "Fast Prototyping And Semi-automated User Interface And Application Generation for Converged Broadcast and Cellular Terminals" [1]. This work involved the development of a service creation application for interactive services on mobile devices and methodologies and tools to speed up and deskill the deployment process. This paper aims at further enhancing these tools and presents an enhanced open standards reference platform for mobile digital TV and rich media services. By using a Scalar Vector Graphics (SVG)-driven Java MIDP application (as opposed to bitmapped raster graphics-driven MHP), rich media services can be broadcast to mobile devices running various Java-supported platforms with a user interface scalable to any screen size. Moreover, the Rich Media Mobile Browser is integrated into a service creation tool, therefore enabling rapid testing and deployment of rich mobile media services.
The following sections detail the motivation behind the need for a platform which allows for rich media play-out on mobile devices, along with the rich media mobile viewing application and the tools used to create and test rich media with speed and ease
The Big Picture on Small Screens Delivering Acceptable Video Quality in Mobile TV
Mobile TV viewers can change the viewing distance and (on some devices) scale the picture to their preferred viewing ratio, trading off size for angular resolution. We investigated optimal trade-offs between size and resolution through a series of studies. Participants selected their preferred size and rated the acceptability of the visual experience on a 200ppi device at a 4: 3 aspect ratio. They preferred viewing ratios similar to living room TV setups regardless of the much lower resolution: at a minimum 14 pixels per degree. While traveling on trains people required videos with a height larger than 35mm
The sweet spot: How people trade off size and definition on mobile devices
Mobile TV can deliver up-to-date content to users on the move. But it is currently unclear how to best adapt higher resolution TV content. In this paper, we describe a laboratory study with 35 participants who watched short clips of different content and shot types on a 200ppi PDA display at a resolution of either 120x90 or 168x128. Participants selected their preferred size and rated the acceptability of the visual experience. The preferred viewing ratio depended on the resolution and had to be at least 9.8H. The minimal angular resolution people required and which limited the up-scaling factor was 14 pixels per degree. Extreme long shots were best when depicted actors were at least 0.7° high. A second study researched the ecological validity of previous lab results by comparing them to results from the field. Image size yielded more value for users in the field than was apparent from lab results. In conclusion, current prediction models based on preferred viewing distances for TV and large displays do not predict viewing preferences on mobile devices. Our results will help to further the understanding of multimedia perception and service designers to deliver both economically viable and enjoyable experiences
Pervasive and standalone computing: The perceptual effects of variable multimedia quality.
The introduction of multimedia on pervasive and mobile communication devices raises a number of perceptual quality issues, however, limited work has been done examining the 3-way interaction between use of equipment, quality of perception and quality of service. Our work measures levels of informational transfer (objective) and user satisfaction (subjective)when users are presented with multimedia video clips at three different frame rates, using four different display devices, simulating variation in participant mobility. Our results will show that variation in frame-rate does not impact a user’s level of information assimilation, however, does impact a users’ perception of multimedia video ‘quality’. Additionally, increased visual immersion can be used to increase transfer of video information, but can negatively affect the users’ perception of ‘quality’. Finally, we illustrate the significant affect of clip-content on the transfer of video, audio and textual information, placing into doubt the use of purely objective quality definitions when considering multimedia
presentations
Principles of Multimedia News Systems for Business Applications
In the past few years considerable demand for business oriented multimedia information systems has developed. A multimedia information system is one that can create, import, integrate, store, retrieve, edit, and delete two or more types of media materials in digital form, such as audio, image, full-motion video, and text information. Multimedia information systems play a central role in many business activities. They represent a very special class complex computing systems. This paper surveys a special type of multimedia information systems: multimedia news systems. Multimedia news systems deal with architectures to manage complex multimedia news databases, online presentation and distribution services or the integration of several existing services to meta-services using intelligent news retrieval engines. The leading presentation platform in multimedia news presentation is news networks providing television services and Internet content distribution. The primary focus is on advanced multimedia news systems infrastructure, document standards, application architecture and principles for multimedia news on the Web that suggest long-term trends in this increasingly important area.multimedia, information systems, business applications
Teaching and learning in virtual worlds: is it worth the effort?
Educators have been quick to spot the enormous potential afforded by virtual worlds for situated and authentic learning, practising tasks with potentially serious consequences in the real world and for bringing geographically dispersed faculty and students together in the same space (Gee, 2007; Johnson and Levine, 2008). Though this potential has largely been realised, it generally isn’t without cost in terms of lack of institutional buy-in, steep learning curves for all participants, and lack of a sound theoretical framework to
support learning activities (Campbell, 2009; Cheal, 2007; Kluge & Riley, 2008). This symposium will explore the affordances and issues associated with teaching and learning in virtual worlds, all the time considering the
question: is it worth the effort
Transforming pre-service teacher curriculum: observation through a TPACK lens
This paper will discuss an international online collaborative learning experience through the lens of the Technological Pedagogical Content Knowledge (TPACK) framework. The teacher knowledge required to effectively provide transformative learning experiences for 21st century learners in a digital world is complex, situated and changing. The discussion looks beyond the opportunity for knowledge development of content, pedagogy and technology as components of TPACK towards the interaction between those three components. Implications for practice are also discussed. In today’s technology infused classrooms it is within the realms of teacher educators, practising teaching and pre-service teachers explore and address effective practices using technology to enhance learning
Faktor-faktor adaptasi logistik terbalik di sektor pembuatan
Dalam dunia yang mempunyai sumber yang terhad, proses pemulihan yang digunakan untuk bahan atau produk adalah kunci untuk menyokong populasi penduduk dalam meningkatkan penggunaan bahan. Pengurangan bahan buangan menjadi kebimbangan kepada industri negara yang berkonsepkan kitaran bahan kerana bahan buangan tersebut merupakan salah satu sumber yang menjana ekonomi industri tersebut. Proses terbalik melibatkan kos yang besar berbanding keuntungan. Perubahan dalam undang-undang untuk melindungi alam sekitar telah memberi kesan kepada ekonomi dan perkhidmatan. Kini, semakin banyak syarikat yang menggunakan proses aliran terbalik untuk pergerakan barangan dalam sistem logistik mereka. Industri pembuatan merupakan industri utama dalam penggunaan aktiviti logistik terbalik. Sistem logistik terbalik merupakan aktiviti yang membentuk proses yang berterusan untuk penggunaan semula produk sama ada digunakan semula ataupun untuk pelupusan. Pembuatan semula ditakrifkan sebagai salah satu kaedah pemulihan yang digunakan untuk produk yang rosak atau bahagian-bahagian yang boleh diperolehi semula dalam keadaan kualiti yang sama dengan produk baharu dan boleh dimasukkan ke dalam produk baharu dan akan dijual semula dalam pasaran sama dengan bahagian atau produk baharu. Aktiviti logistik terbalik sering dilaksanakan oleh pengeluar asal kerana bahan yang digunakan semula diperlukan untuk pengetahuan dalam pengeluaran tertentu. Eltayeb dan Zailani (2010) menyatakan kebanyakan pengeluar di Malaysia tidak berminat untuk menggunakan semula barangan kitar semula atau pelupusan disebabkan oleh perbelanjaan tambahan untuk mengendalikan aktiviti yang berkaitan dengan logistik terbalik
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