Spelling suggestions: "subject:"[een] MPEG"" "subject:"[enn] MPEG""
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Personal Mobile CommunicatorZheng, Yao-Jei 23 July 2002 (has links)
Increases in bandwidth and computational speed lead to growing interests in real-time audio and video communication over the Internet. With dramatic increase in wireless access recently, a challenging problem associated with audio and video communication lies in how to cope with packet loss and achieve acceptable video quality at the receiver and utilizing the limited wireless bandwidth efficiently.
In this paper, we implement a system, Personal Mobile Communicator, to offer video and audio streaming communication. We employ MPEG-4 and GSM to compress video and audio data. MPEG-4 and GSM provide the standardized technological elements to compress video and audio data. MPEG-4 also takes a number of steps to enable robust transmission of compressed video data over noisy communication channels.
We implement error resilience tools for reliable transmission and error concealment technologies to provide better video quality when error occurred.
The goal of this paper, we design a communication system that is suitable for communication over wireless channel and offer a verification platform for further research.
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New Intra and Inter Shape Coding Algorithms for MPEG-4Bian, Shiu-Hong 09 September 2002 (has links)
In this paper, new intra and inter shape coding algorithms are proposed. The new algorithms are based on chain code. Chain code of an object's contour can be divided into several segments by the smooth contour characteristic. By this property, some techniques can be used for the proposed intra and inter shape coding algorithms. In intra mode, each segment is encoded by specific codes, and the decoding result is lossless. Compared with MPEG-4, M4R, DCC and chain code, the compression ratio is improved. Besides, a new coding scheme is proposed for the inter shape coding. It includes finding break points in a series of chain code, correlation between break points and fine scaling with a tolerant threshold between two similar chain code segments. By detecting the segments, break points can be found. The correlation is performed by computing the curvature difference between break points and contour points. The scaling is a technique for extending or shrinking a segment of chain code. Experimental results show that in the condition of high quality or low bit rate our proposed inter shape coding algorithm obtains better performance than MPEG-4 in compression.
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Multi-step-ahead prediction of MPEG-coded video source traffic using empirical modeling techniquesGupta, Deepanker 12 April 2006 (has links)
In the near future, multimedia will form the majority of Internet traffic and
the most popular standard used to transport and view video is MPEG. The MPEG
media content data is in the form of a time-series representing frame/VOP sizes.
This time-series is extremely noisy and analysis shows that it has very long-range
time dependency making it even harder to predict than any typical time-series. This
work is an effort to develop multi-step-ahead predictors for the moving averages of
frame/VOP sizes in MPEG-coded video streams.
In this work, both linear and non-linear system identification tools are used to
solve the prediction problem, and their performance is compared. Linear modeling is
done using Auto-Regressive Exogenous (ARX) models and for non linear modeling,
Artificial Neural Networks (ANN) are employed. The different ANN architectures
used in this work are Feed-forward Multi-Layer Perceptron (FMLP) and Recurrent
Multi-Layer Perceptron (RMLP).
Recent researches by Adas (October 1998), Yoo (March 2002) and Bhattacharya
et al. (August 2003) have shown that the multi-step-ahead prediction of individual
frames is very inaccurate. Therefore, for this work, we predict the moving average
of the frame/VOP sizes instead of individual frame/VOPs. Several multi-step-ahead
predictors are developed using the aforementioned linear and non-linear tools for
two/four/six/ten-step-ahead predictions of the moving average of the frame/VOP
size time-series of MPEG coded video source traffic.
The capability to predict future frame/VOP sizes and hence the bit rates will
enable more effective bandwidth allocation mechanism, assisting in the development
of advanced source control schemes needed to control multimedia traffic over wide
area networks, such as the Internet.
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Adaptation de contenu multimédia avec MPEG 21 : conversion de ressources et adaptation sémantique de scènes /Kimiaei Asadi, Mariam. January 1900 (has links)
Thèse de doctorat--Informatique et réseaux--Paris--ENST, 2005. / MPEG = Moving picture experts group. Bibliogr. p. 201-206. Résumé en anglais et en français.
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New techniques for streaming MPEG video over the internet /Zhou, Jian, January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 112-118).
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Plate-forme ouverte pour contenus et traitements multimédias en ligneLe Bonhomme, Benoît 14 December 2009 (has links) (PDF)
L'émergence des contenus multimédias sur Internet, l'accès aux contenus multimédias et leurs enrichissements constituent un vaste domaine de recherche. Cette thèse s'inscrit dans ce contexte, et présente la réalisation complète et opérationnelle d'une plate-forme de diffusion multimédia interopérable et ouverte. Après avoir spécifié l'architecture de la plate-forme en introduisant le support de tous types de médias, l'indexation efficace, la recherche de contenus et leurs visualisations en ligne, la première contribution de cette thèse est une extension de la norme MPEG 7 permettant d'assurer la gestion des contenus graphiques 3D, ainsi que des informations liées à un système multimédia. Cette extension a permis le développement d'une plate-forme de diffusion gérant tous types de contenus, appelée MyMultimédiaWorld.com, entièrement normalisée à l'aide de MPEG 7 et MPEG 4. La deuxième contribution porte sur les facilités d'accès à la plate-forme multimédia. D'une part, nous avons développé une solution simple et originale d'API d'accès aux contenus multimédia par de applications tierces. D'autre part, nous proposons une solution basée sur le principe d'API pour intégrer dans une plate-forme des algorithmes multimédias. Cette solution permet la création de nouveaux services à partir d'algorithmes externes. A partir des deux APIs, nous proposons une nouvelle approche pour l'évaluation automatique d'algorithmes multimédias. Les aspects clés de cette approche sont l'évaluation en ligne, des conditions identiques pour l'exécution des algorithmes et la mise à jour automatique des résultats. L'approche développée est démontrée à l'aide de deux benchmarks différents, le premier pour l'évaluation des algorithmes de compression de maillage 3D et le second pour le benchmark des descripteurs de formes 3D développé dans le cadre des projets FAME2 et POPS du pôle de compétitivité System@tic. Les avantages de cette approche ont été reconnus récemment par le comité de normalisation MPEG avec sa décision d'adopter www.MyMultimédiaWorld.com pour l'évaluation des algorithmes de compression de maillage 3D.
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Compression and packetised transport of model-based video dataWoods, John Charles January 2000 (has links)
No description available.
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Remote news reports over digital cellular networksNeale, Jason January 1999 (has links)
No description available.
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Combining Image Features For Semantic DescriptionsSoysal, Medeni 01 January 2003 (has links) (PDF)
Digital multimedia content production and the amount of content present all
over the world have exploded in the recent years. The consequences of this fact
can be observed everywhere in many different forms, to exemplify, huge digital
video archives of broadcasting companies, commercial image archives, virtual
museums, etc. In order for these sources to be useful and accessible, this
technological advance must be accompanied by the effective techniques of
indexing and retrieval. The most effective way of indexing is the one providing a
basis for retrieval in terms of semantic concepts, upon which ordinary users of
multimedia databases base their queries. On the other hand, semantic
classification of images using low-level features is a challenging problem.
Combining experts with different classifier structures, trained by MPEG-7low-level color and texture descriptors, is examined as a solution alternative. For
combining different classifiers and features, advanced decision mechanisms are
proposed, which utilize basic expert combination strategies in different settings.
Each of these decision mechanisms, namely Single Feature Combination (SFC),
Multiple Feature Direct Combination (MFDC), and Multiple Feature Cascaded
Combination (MFCC) enjoy significant classification performance improvements
over single experts. Simulations are conducted on eight different visual semantic
classes, resulting in accuracy improvements between 3.5-6.5%, when they are
compared with the best performance of single expert systems.
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Flexible scheduling for media processing in resource constrained real-time systems /Isović, Damir, January 2004 (has links) (PDF)
Diss. Västerås : Mälardalens högskola, 2004.
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