Evaluation of subjective video quality of mobile devices,”

ABSTRACT Subjectively perceived video quality is a critical factor when adopting new mobile video applications. When video is used in mobile networks the most important requirements are related to low bitrates, framerates and the screen size of mobile device. In two tests we investigated the effects of codecs and combinations of audio and video streams with low bitrates and different contents on the perceived video quality of mobile devices. The first test showed that the codec H.264 produced the most satisfying video quality, but the quality was not high enough for the presentation of textual information. In the second test, the audio-video ratio 32/128kbps was found to be the most pleasant, but there were content dependent variations

Descriptive quality of experience for mobile 3D video

ilmenau.de} Perceptual quality evaluation experiments are used to assess the excellence of multimedia quality. However, these studies disregard qualitative experiential descriptions, interpretations, and impressions of quality. The goal of this paper is to identify general descriptive characteristics of experienced quality of 3D video on mobile devices. We conducted five studies in which descriptive data was collected after the psychoperceptual quality evaluation experiment. Qualitative semi-structured interviews and written attribute description tasks were conducted with over 90 naïve participants. The experiments contained an extensive and heterogeneous set of produced quality by varying content, level of depth, compression and transmission parameters, and audio and display factors for 3D. The results showed that quality of experience is constructed from four main components, 1) visual quality, 2) viewing experience, 3) content, and 4) quality of other modalities and their interactions. Author Keywords Quality perception, quality of experience, multimedia, 3

User perception of media content association in olfaction-enhanced multimedia

Olfaction is an exciting challenge facing multimedia applications. In this article we have investigated user perception of the association between olfactory media content and video media content in olfactory-enhanced multimedia. Results show that the association between scent and content has a significant impact on the user-perceived experience of olfactory-enhanced multimedia

Engineering context-aware systems and applications:A survey

Context-awareness is an essential component of systems developed in areas like Intelligent Environments, Pervasive & Ubiquitous Computing and Ambient Intelligence. In these emerging fields, there is a need for computerized systems to have a higher understanding of the situations in which to provide services or functionalities, to adapt accordingly. The literature shows that researchers modify existing engineering methods in order to better fit the needs of context-aware computing. These efforts are typically disconnected from each other and generally focus on solving specific development issues. We encourage the creation of a more holistic and unified engineering process that is tailored for the demands of these systems. For this purpose, we study the state-of-the-art in the development of context-aware systems, focusing on: (A) Methodologies for developing context-aware systems, analyzing the reasons behind their lack of adoption and features that the community wish they can use; (B) Context-aware system engineering challenges and techniques applied during the most common development stages; (C) Context-aware systems conceptualization

Opetuksen laatu ja opetuksen kehittäminen TTY:n opiskelijoiden näkökulmasta

Työn tavoitteena oli selvittää Tampereen teknillisen yliopiston opiskelijoiden käsityksiä opetuksen laadusta ja opetuksen kehityskohteita. Kyselytutkimukse-na suoritetussa aineistonkeruussa kerättiin sekä määrällistä ja laadullista aineistoa mukavuusotantaa käyttäen. Kyselyyn vastanneet 393 opiskelijaa olivat laajasti eri koulutusohjelmista sekä eri vaiheessa opintojaan. Kyselyn määrällisessä osuudessa hyödynnettiin olemassa olevaa ETLQ-mittaria (Experiences of Teaching and Learning Questionnaire). Analyysissä käytettiin faktorianalyysiä keskeisten TTY:n opetuksen laadun tekijöiden erotte-luun. Varianssianalyysin avulla vertailtiin eroavuuksia opetuksen laadusta eri opintojen vaiheissa olevien opiskelijoiden välillä. Laadullinen aineisto kerättiin projektiivisella lauseentäydennystehtävällä, jonka tavoitteena oli selvittää kes-keisiä opetuksen kehityskohteita opiskelijoiden mielestä. Analyysissä käytettiin aineistolähtöistä sisällönanalyysiä. Synteesi tutkimustuloksista nosti esille neljä keskeistä kehityskohdetta. 1. Opiskelijat kokevat tarvitsevansa parempaa palautetta oppimisestaan, tukea opiskelustrategioilleen sekä vaihtoehtoisia suoritustapoja. 2. Opiskelijat tarvitsevat myös tukea opiskeltavien asioiden ymmärtämiseen ja kriittiseen ajatteluun täh-täävässä oppimisessa. 3. Luento-opetukseen opiskelijat kaipaisivat enemmän heitä aktivoivia tehtäviä, harjoitteita, sekä monipuolisia esitystapoja ja medioiden käyttöä tarkkaavaisuuden ylläpitämiseksi. 4. Opiskelijat jäivät kaipaamaan opettajan innostuneisuutta, parempaa viestintää, opetustaitojen kehittämistä sekä aitoa opiskelijan ymmärtämistä ja heidän oppimaan oppimisen tukemista. Aineistoa kertyi laajalti ja jatkossa samaa aineistoa voidaan käyttää pohdittaessa, mitä vaikutusta opiskelijoiden opiskelustrategioilla on heidän käsityksiinsä opetuksen laadusta. Tämän kehittämishankkeen tulokset julkaistaan koko yliopiston käyttöön ja niitä käytetään hyväksi myös opetuksen kehittämistyöryhmissä

Who is moving – user or device?: Experienced quality of mobile 3D video in vehicles

Viewing while commuting’ is a typical use case for mobile video. However, experimental and behavioral influences of watching three-dimensional (3D) video in vibrating vehicles have not been widely researched. The goal of this study is 1) to explore the influence of video presentation modes (two-dimensional and stereoscopic 3D) on the quality of experience and 2) to understand the nature of the movement patterns that users perform to maintain an optimal viewing position while viewing videos on a mobile device in three commuting contexts and in a controlled laboratory environment. A hybrid method for quality evaluation was used for combining quantitative preference ratings, qualitative descriptions of quality, situational audio/video data-collection, and sensors. The high-quality and heterogeneous audiovisual stimuli were viewed on a mobile device equipped with a parallax barrier display. The results showed that the stereoscopic 3D (S3D) video presentation mode provided more satisfying quality of experience than the two-dimensional presentation mode in all studied contexts. To maintain an optimal viewing position in the vehicles, the users moved the device in their hands to the directions around the vertical and the horizontal axes in a leaned sitting position. This movement behavior was guided by the contexts but not by the quality, indicating the general importance of these results for mobile video viewing in vibrating vehicles

User Experience of Digital News : Two Semi-long Term Field Studies

Reading of digital news on personal devices has dramatically increased. Parallel to new devices, novel service or even content types are created forming new habits and experiences for readers. However, previous research is limited in understanding temporal aspects of such users’ experiences (UX). The goal of this study is to understand user experience of mobile news reading in a real context of use over one week in two different case studies. UX of digital replicas, browser optimized versions of digital news, and novel media authentication method for news reading and ordering were explored with actual news readers (N=36) in field using their own tablets and personal computers. Data-collection included in daily diaries with the UX questionnaires and the retrospective interviews. The results showed that the studied forms of digital news and authentication methods provided positive user experience and they were appealing for future digital news. UX also showed a tendency of improving over a time. In addition, the user’s habits of reading digital news reflected the conventions of reading a print newspaper.submittedVersionPeer reviewe