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1
Hill, Alberto Daniel. "MPEG-4 sobre CATV." Diss., Universidad Católica del Uruguay, 2003. http://hdl.handle.net/10919/71550.
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This dissertation study describes and presents an alternative method for delivering digital video, the MPEG-4 compression format, through the use of an analog cable network for direct viewing on television sets. The purpose of the study is to propose this technology as an alternative to the present cable network technologies in Uruguay and elsewhere in South America. Delivery standards that might be used over such a CATV network include DVB-C (digital video broadcast for cable), and IP (internet protocol) networks.
The study compares the current technologies to determine which would be the best way to provide such delivery over CATV networks. It is the argument of this study that the delivery of MPEG-4 format streaming video is no different than the delivery of any type of digital signal: in order for the signal to be delivered, it must pass through a transmission medium such as fiber-optic cable, twisted-wire pair, coaxial cable, etc.
The dissertation makes the case that MPEG-4 is a feasible alternative technology which should be considered for new CATV applications in this region. This study is from a technical point of view, when it comes to implementation there are other elements that should be taken into account.
2
Bouilhaguet, Frédéric. "Architecture de systèmes MPEG-4." Paris, ENST, 2001. http://www.theses.fr/2001ENST0044.
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Boughoufalah, Souhila. "Outils auteurs pour MPEG-4." Paris : École nationale supérieure des télécommunications, 2003. http://catalogue.bnf.fr/ark:/12148/cb390852679.
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4
Bouilhaguet, Frédéric. "Architecture de systèmes MPEG-4 /." Paris : École nationale supérieure des télécommunications, 2002. http://catalogue.bnf.fr/ark:/12148/cb38946295c.
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Hasnaoui, Marwen. "MPEG-4 AVC stream watermarking." Phd thesis, Institut National des Télécommunications, 2014. http://tel.archives-ouvertes.fr/tel-01048697.
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The present thesis addresses the MPEG-4 AVC stream watermarking and considers two theoretical and applicative challenges, namely ownership protection and content integrity verification.From the theoretical point of view, the thesis main challenge is to develop a unitary watermarking framework (insertion/detection) able to serve the two above mentioned applications in the compressed domain. From the methodological point of view, the challenge is to instantiate this theoretical framework for serving the targeted applications. The thesis first main contribution consists in building the theoretical framework for the multi symbol watermarking based on quantization index modulation (m-QIM). The insertion rule is analytically designed by extending the binary QIM rule. The detection rule is optimized so as to ensure minimal probability of error under additive white Gaussian noise distributed attacks. It is thus demonstrated that the data payload can be increased by a factor of log2m, for prescribed transparency and additive Gaussian noise power. A data payload of 150 bits per minute, i.e. about 20 times larger than the limit imposed by the DCI standard, is obtained. The thesis second main theoretical contribution consists in specifying a preprocessing MPEG-4 AVC shaping operation which can eliminate the intra-frame drift effect. The drift represents the distortion spread in the compressed stream related to the MPEG encoding paradigm. In this respect, the drift distortion propagation problem in MPEG-4 AVC is algebraically expressed and the corresponding equations system is solved under drift-free constraints. The drift-free shaping results in gain in transparency of 2 dB in PSNR
6
Hasnaoui, Marwen. "MPEG-4 AVC stream watermarking." Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2014. http://www.theses.fr/2014TELE0009.
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La présente thèse aborde le sujet de tatouage du flux MPEG-4 AVC sur ses deux volets théoriques et applicatifs en considérant deux domaines applicatifs à savoir la protection du droit d’auteur et la vérification de l'intégrité du contenu. Du point de vue théorique, le principal enjeu est de développer un cadre de tatouage unitaire en mesure de servir les deux applications mentionnées ci-dessus. Du point de vue méthodologique, le défi consiste à instancier ce cadre théorique pour servir les applications visées. La première contribution principale consiste à définir un cadre théorique pour le tatouage multi symboles à base de modulation d’index de quantification (m-QIM). La règle d’insertion QIM a été généralisée du cas binaire au cas multi-symboles et la règle de détection optimale (minimisant la probabilité d’erreur à la détection en condition du bruit blanc, additif et gaussien) a été établie. Il est ainsi démontré que la quantité d’information insérée peut être augmentée par un facteur de log2m tout en gardant les mêmes contraintes de robustesse et de transparence. Une quantité d’information de 150 bits par minutes, soit environ 20 fois plus grande que la limite imposée par la norme DCI est obtenue. La deuxième contribution consiste à spécifier une opération de prétraitement qui permet d’éliminer les impactes du phénomène du drift (propagation de la distorsion) dans le flux compressé MPEG-4 AVC. D’abord, le problème a été formalisé algébriquement en se basant sur les expressions analytiques des opérations d’encodage. Ensuite, le problème a été résolu sous la contrainte de prévention du drift. Une amélioration de la transparence avec des gains de 2 dB en PSNR est obtenue<br>The present thesis addresses the MPEG-4 AVC stream watermarking and considers two theoretical and applicative challenges, namely ownership protection and content integrity verification.From the theoretical point of view, the thesis main challenge is to develop a unitary watermarking framework (insertion/detection) able to serve the two above mentioned applications in the compressed domain. From the methodological point of view, the challenge is to instantiate this theoretical framework for serving the targeted applications. The thesis first main contribution consists in building the theoretical framework for the multi symbol watermarking based on quantization index modulation (m-QIM). The insertion rule is analytically designed by extending the binary QIM rule. The detection rule is optimized so as to ensure minimal probability of error under additive white Gaussian noise distributed attacks. It is thus demonstrated that the data payload can be increased by a factor of log2m, for prescribed transparency and additive Gaussian noise power. A data payload of 150 bits per minute, i.e. about 20 times larger than the limit imposed by the DCI standard, is obtained. The thesis second main theoretical contribution consists in specifying a preprocessing MPEG-4 AVC shaping operation which can eliminate the intra-frame drift effect. The drift represents the distortion spread in the compressed stream related to the MPEG encoding paradigm. In this respect, the drift distortion propagation problem in MPEG-4 AVC is algebraically expressed and the corresponding equations system is solved under drift-free constraints. The drift-free shaping results in gain in transparency of 2 dB in PSNR
7
Lundberg, Jonas. "MPEG-4 Facial Feature Point Editor." Thesis, Linköping University, Department of Electrical Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1401.
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<p>The use of computer animated interactive faces in film, TV, games is ever growing, with new application areas emerging also on the Internet and mobile environments. Morph targets are one of the most popular methods to animate the face. Up until now 3D artists had to design each morph target defined by the MPEG-4 standard by hand. This is a very monotonous and tedious task. With the newly developed method of Facial Motion Cloning [11]the heavy work is relieved from the artists. From an already animated face model the morph targets can now be copied onto a new static face model. </p><p>For the Facial Motion Cloning process there must be a subset of the feature points specified by the MPEG-4 standard defined. The purpose of this is to correlate the facial features of the two faces. The goal of this project is to develop a graphical editor in which the artists can define the feature points for a face model. The feature points will be saved in a file format that can be used in a Facial Motion Cloning software.</p>
8
Carvalho, Diego Fiori de. "Esteganografia em vídeos comprimidos MPEG-4." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-08062009-143448/.
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A esteganografia em vídeos digitais possibilita o ocultamento de um grande volume de informações quando comparada a técnicas em imagens. Contudo, esta tarefa não é trivial quando aplicada a vídeos comprimidos, pois a inserção de informações ocultas pode adicionar ruído dificultando a perfeita recuperação das mesmas durante a decodificação. Este trabalho apresenta uma técnica para esteganografia em vídeos comprimidos, denominada MP4Stego, a qual explora estruturas e tecnologias do padrão de vídeo MPEG-4 de modo a proceder recuperação de informações sem perda e apresentar maior capacidade de inserção de dados ocultos. Entre os benefícios da técnica estão: A capacidade de ocultamento de grande volume de dados; a capacidade de reprodução do vídeo contendo dados ocultos em players não especializados (ajudando a dar a ilusão de que se trata de um vídeo comum), sua imunidade, até o momento, as técnicas de esteganálise<br>Digital video steganography makes possible to hide higher volumes of information than the broadly used image steganography techniques. However, apply steganography to compressed digital videos is not a trivial task because the information hiding process may add noise to the original data. In this way, during the video decoding, the recovered hidden information is not an exact copy of the original data. This work presents a new steganographic technique, called MP4Stego, which explores new video structures of the MPEG-4 standard in order to recover hidden data without loss and in order to provide higher capacity of hidden data insertion. Some benefits of the MP4Stego technique are: to hide high volumes of data; to playback steganographyed videos by the means of non specialized players (this helps users to think that it is a regular video); so far, its immunity to stegoanalysis techniques
9
Leupold, Jan. "MPEG-4 Szenenbeschreibung in Telepräsenz-Szenarien." kostenfrei, 2008. http://mediatum2.ub.tum.de/doc/647001/647001.pdf.
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10
Gallardo, Adriana. "MPEG-4 video prioritisation over Wireless LAN." Thesis, University of Bristol, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440255.
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Santos, Marco Paulo Carvalho Ribeiro dos. "Codificação de vídeo MPEG-4 em FPGA." Master's thesis, Universidade de Aveiro, 2007. http://hdl.handle.net/10773/4676.
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Mestrado em Engenharia Electrónica e Telecomunicações<br>O trabalho apresentado nesta dissertação foi realizado no âmbito do grupo ISG
(Implementation Study Group) do MPEG (Motion Picture Expert Group). Tem
como objectivo principal analisar o desempenho da implementação de
diversões módulos da norma MPEG-4 e da sua versão avançada MPEG-4
AVC (Advanced Video Coding) em FPGA (Field Programmable Gate Array). A
dissertação é essencialmente constituída por duas partes. Na primeira parte,
estudam-se os conceitos básicos da codificação de vídeo, nomeadamente os
conceitos integrantes da norma MPEG-4. De seguida, estuda-se a norma
MPEG-4 AVC. Na segunda parte, esta dissertação apresenta o
desenvolvimento de seis módulos implementados em VHDL e compilados para
o circuito FPGA da XILINX, Virtex-II. Dos seis módulos, quatro constituem um
descodificador MPEG-4 (excepto a compensação de movimento) enquanto os
outros dois fazem parte do codificador MPEG-4 AVC.<br>This dissertation shows the work developed in the framework of the ISG
(Implementation Study Group) group. The main objective of this work is to
analyse the performance of several MPEG-4 modules and MPEG-4 AVC
(Advanced Video Coding) modules in FPGA (field Programmable Gate Array).
This dissertation is organized into two parts. In the first part, the basic video
coding concepts are studied, mainly the MPEG-4 concepts, followed by the
MPEG-4 AVC standard. In the second part, it is discussed six modules
implemented in VHDL and compiled for the XILINX Virtex-II FPGA. Four of
those six developed modules are used to implement an MPEG-4 decoder
(except the motion compensation stage) and the other two are modules of the
MPEG-4 AVC coder.
12
Le, Bonhomme Benoît. "Plate-forme ouverte pour contenus et traitements multimédias en ligne." Phd thesis, Institut National des Télécommunications, 2009. http://tel.archives-ouvertes.fr/tel-00541852.
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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.
13
Hamosfakidis, Anastasios. "MPEG-4 software video encoding using parallel processing." Thesis, Queen Mary, University of London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436200.
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14
Sohm, Oliver Peter. "Optimisation of video coding algorithms for VLIW-type processors." Thesis, University of Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271859.
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Rudol, Piotr, and Mariusz Wzorek. "Editing, Streaming and Playing of MPEG-4 Facial Animations." Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1687.
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<p>Computer animated faces have found their way into a wide variety of areas. Starting from entertainment like computer games, through television and films to user interfaces using “talking heads”. Animated faces are also becoming popular in web applications in form of human-like assistants or newsreaders. </p><p>This thesis presents a few aspects of dealing with human face animations, namely: editing, playing and transmitting such animations. It describes a standard for handling human face animations, the MPEG-4 Face Animation, and shows the process of designing, implementing and evaluating applications compliant to this standard. </p><p>First, it presents changes introduced to the existing components of the Visage|toolkit package for dealing with facial animations, offered by the company Visage Technologies AB. It also presents the process of designing and implementing of an application for editing facial animations compliant to the MPEG-4 Face Animation standard. Finally, it discusses several approaches to the problem of streaming facial animations over the Internet or the Local Area Network (LAN).</p>
16
Cai, Wei Kougianos Elias Mohanty Saraju. "FPGA prototyping of a watermarking algorithm for MPEG-4." [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3695.
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Meine, Nikolaus. "Vektorquantisierung und kontextabhängige arithmetische Codierung für MPEG-4 AAC /." Düsseldorf : VDI-Verl, 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016378661&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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COSTA, ROMUALDO MONTEIRO DE RESENDE. "INTEGRATION AND INTEROPERABILITY OF MPEG-4 AND NCL DOCUMENTS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=6661@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>A abordagem orientada a objetos do padrão MPEG-4, para a
codificação de
conteúdo audiovisual, é similar às utilizadas em vários
modelos e linguagens de
especificação de documentos multimídia/hipermídia. Entre
essas linguagens, a
NCL (Nested Context Language), utilizada no sistema
HyperProp, introduz uma
série de novos conceitos que podem ser integrados ao
padrão, com vantagens.
Esta dissertação propõe, inicialmente, a conversão de
documentos especificados
em NCL para MPEG-4 (XMT-O) e vice-versa, permitindo que
ferramentas de
autoria e formatação possam ser utilizadas na
especificação e exibição de
documentos de ambas as linguagens. Este trabalho também
propõe a incorporação
de cenas MPEG-4 tanto como objetos de mídia quanto
composições da linguagem
NCL, permitindo o estabelecimento de relacionamentos entre
cenas. Para permitir
a exibição desses novos objetos NCL, é incorporado ao
Formatador HyperProp
um exibidor MPEG-4 capaz de reportar ao controlador a
ocorrência de eventos
que, entre outras coisas, permite o sincronismo entre
cenas MPEG-4 e outros
objetos NCL, incluindo outras cenas MPEG-4. Por fim,
explorando o conceito de
templates introduzido pela linguagem NCL, a capacidade de
autoria no MPEG-4 é
estendida, através da definição de novas semânticas para
as composições da
linguagem XMT-O e da concepção de compiladores para essa
linguagem.<br>The MPEG-4 standard object-oriented approach, employed to
the encoding
of audiovisual content, is similar to those used on many
models and languages for
multimedia/hypermedia document specification. Among those
languages, the
NCL (Nested Context Language), used in the HyperProp
system, introduces a
series of new concepts that can be integrated to the
standard, with advantages.
Initially, the proposal of this work is to convert NCL to
MPEG-4 (XMT-O)
documents and vice versa, allowing authoring and
formatting tools to be used in
the specification and presentation of documents in both
languages. This work also
proposes both the placing of MPEG-4 scenes as media
objects and NCL language
compositions, allowing the establishment of relationships
among scenes. In order
to allow displaying these new NCL objects, an MPEG-4
player is incorporated to
the HyperProp Formatter. The MPEG-4 player is able to
report to the controller
the occurrence of events that, among other things, allows
the synchronization
between MPEG-4 scenes and othe r NCL objects, including
other MPEG-4 scenes.
Finally, exploring the concept of templates, introduced by
the NCL language, the
authoring in the MPEG-4 is improved, by means of the
definition of new
semantics for XMT-O language compositions and the design
of compilers for this
language.
19
Cai, Wei. "FPGA Prototyping of a Watermarking Algorithm for MPEG-4." Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc3695/.
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In the immediate future, multimedia product distribution through the Internet will become main stream. However, it can also have the side effect of unauthorized duplication and distribution of multimedia products. That effect could be a critical challenge to the legal ownership of copyright and intellectual property. Many schemes have been proposed to address these issues; one is digital watermarking which is appropriate for image and video copyright protection. Videos distributed via the Internet must be processed by compression for low bit rate, due to bandwidth limitations. The most widely adapted video compression standard is MPEG-4. Discrete cosine transform (DCT) domain watermarking is a secure algorithm which could survive video compression procedures and, most importantly, attacks attempting to remove the watermark, with a visibly degraded video quality result after the watermark attacks. For a commercial broadcasting video system, real-time response is always required. For this reason, an FPGA hardware implementation is studied in this work. This thesis deals with video compression, watermarking algorithms and their hardware implementation with FPGAs. A prototyping VLSI architecture will implement video compression and watermarking algorithms with the FPGA. The prototype is evaluated with video and watermarking quality metrics. Finally, it is seen that the video qualities of the watermarking at the uncompressed vs. the compressed domain are only 1dB of PSNR lower. However, the cost of compressed domain watermarking is the complexity of drift compensation for canceling the drifting effect.
20
Goularte, Rudinei. "Personalização e adaptação de conteúdo baseadas em contexto para TV Interativa." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-23092004-153330/.
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O trabalho apresentado nesta tese trata do desenvolvimento de técnicas com suporte à ciência de contexto, baseadas nos padrões MPEG-4 e MPEG-7, para personalizar e adaptar conteúdo em TV Interativa. Um dos desafios dessa área é desenvolvimento de programas personalizados com rico conteúdo multimídia, com alta interatividade e que, além disso, sejam acessíveis a partir de uma variedade de dispositivos (fixos ou móveis), atendendo às expectativas de interação e de acesso dos usuários. Grande parte do problema está no fato de que os modos encontrados na literatura para representar, descrever e compor programas de TV Interativa não oferecem suporte a contexto, não permitem a separação entre descrições de programas e descrições de objetos e possuem baixa granulosidade de segmentação. Essas características dificultam e, em alguns casos, impedem o desenvolvimento de aplicações avançadas em TV Interativa. As técnicas desenvolvidas neste trabalho são baseadas em esquemas de descrição, compatíveis com o padrão MPEG-7, e na segmentação de programas em objetos MPEG-4. Os esquemas são utilizados para descrever a estrutura, a composição e a semântica de programas e de seus objetos componentes. Também foi definida e implantada uma infra-estrutura para produção, distribuição e consumo de programas. A utilização conjunta da infra-estrutura e das técnicas permite o desenvolvimento de aplicações avançadas em TV Interativa. Como um exemplo dessas aplicações, foi desenvolvido um serviço automático para personalizar e adaptar programas de TV Interativa, permitindo que um usuário possa acessar, sob demanda, programas especialmente produzidos para ele, contendo apenas assuntos de seu interesse e permitindo que o acesso possa ser realizado por dispositivos fixos ou móveis.<br>The work presented in this thesis developed techniques with context-awareness support, based on the MPEG-4 and MPEG-7 standards, in order to personalize and to adapt Interactive TV content. One of the challenges in this area is the development of personalized programs with rich multimedia content, high interactivity and accessibility through a variety of devices (mobile and non-mobile). Most part of the problem is that the approaches found in literature do not provide context support, do not allow separation between programs and objects descriptions and have low level of segmentation granularity. These features make difficult or impossible, in some cases, the development of Interactive TV applications. The techniques developed in this work are based on MPEG-7 compliant schemes and on programs segmentation into MPEG-4 objects. The schemes are used to describe structure, composition and semantics of programs and component objects. An infra-structure to creation, delivery and consumption of Interactive TV programs was also defined. The joint utilization of infra-structure and techniques allows for the development of Interactive TV advanced applications. As an example of these applications, this work developed an automatic Interactive TV personalization and adaptation service. This service allows a user to access, on-demand, a program specially designed to match his interests and allowing content access through devices with mobile and non-mobile features.
21
Vassaux, Boris. "Technique multicouches pour le tatouage d'images et adaptation aux flux vidéo MPEG-2 et MPEG-4." Grenoble INPG, 2003. http://www.theses.fr/2003INPG0105.
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Le tatouage de documents numériques est une discipline qui consiste à insérer une signature invisible dans une image, une séquence vidéo ou une séquence audio. Nous présentons dans ce mémoire différentes contributions dans le domaine du tatouage d'images et de vidéos. Dans un premier temps, nous explicitons les enjeux du tatouage de documents et les différentes applications de la discipline. Nous proposons à cette occasion une classification des schémas de tatouage d'images et de vidéos ainsi que des attaques sur ces schémas rencontrées dans la littérature. Nous distinguons les attaques non intentionnelles des attaques malveillantes. Les trois chapitres suivants sont consacrés aux techniques novatrices que nous avons développées au cours de la thèse. Dans le chapitre 3 nous présentons la méthode multicouche en tatouage d'images. Cette méthode novatrice s'inspire de la technique CDMA (Code Division Multi Access) qui est habituellement éprouvée en communication. Appliquée au tatouage d'images, elle permet de pouvoir insérer une quantité d'information plus importante dans une image sans pour autant la dégrader davantage. Dans le chapitre suivant nous présentons la suite logique qui consiste à doter la méthode multicouche d'une technique qui lui permette d'être résistante à certaines distorsions asynchrones. Nous utilisons l'Analyse en Composantes Principales qui permet à la méthode d'être notamment robuste à des rotations. Dans le chapitre 5, nous envisageons l'implantation de cette méthode pour le tatouage de vidéos. Après avoir présenté une technique adaptée à la compression MPEG-2 pour anticiper les problèmes en tatouage dus aux changements de format, nous présentons la technique novatrice du brouillage directionnel. Cette technique, habituellement éprouvée en cryptographie, nous permet d'adapter l'algorithme multicouche aux contraintes de la norme de compression MPEG-4, notamment l'utilisation d'objets vidéos.
22
Junior, João Benedito dos Santos. "Modelagem de ambientes interativos conscientes de contexto: uma abordagem baseada nos padrões MPEG-4 e MPEG-7." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-03062015-105735/.
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Novas formas de interação têm surgido a partir da disseminação das tecnologias associadas á multimídia interativa. O uso de objetos multiinídia apresenta-se, num primeiro momento, como um bónus para muitas aplicações, porém, no contexto no qual este trabalho se insere, pretende-se investigar as possibilidades para o usuário interagir com objetos multimídia, durante a apresentação desses objetos, com características que ultrapassem os limites dos tradicionais controles VCR (Vídeo- Cassette Recorder). Adicionalmente, a apresentação de um vídeo interativo pode ser influenciada e/ou modificada por eventos que ocorrem no ambiente no qual a aplicação multimídia estiver inserida. Neste cenário, o ambiente - visto neste trabalho como sendo a infra-estrutura de comunicação, a aplicação, as mídias e os terminais para interação - pode exigir adaptações na interface do usuário e o ajuste nos parâmetros de distribuição e consumo dos streams elementares de mídia. Tecnologias, técnicas e padrões têm sido produzidos para viabilizar o desenvolvimento dessas novas aplicações multimídia; entretanto, muitas dessas novas formas de interação continuam inexploradas e não formalizadas. O principal objetivo desta tese1 é apresentar uma proposta para a modelagem de ambientes interativos conscientes de contexto, utilizando a linguagem UML (Unified Modelling Language), tendo como infra-estrutura tecnológica os padrões MPEG-4 e MPEG-7 da família de padrões MPEG (Moving Picture Expert Group) e considerando as informações contextuais como uma forma para facilitar e incrementar a interação do usuário com essas novas aplicações multimídia interativos. O trabalho descreve um cenário para aplicações interativas com base nos padrões MPEG-4 e MPEG-7, no qual seja possível aplicar os conceitos de consciência de contexto como forma para oferecer suporte ao desenvolvimento de novos sistemas multimídia interativos. Neste sentido, novos critérios de interação foram estabelecidos a partir da distribuição de conteúdo multimídia (representado por objetos MPEG-4) e informação associada ao conteúdo, descrita por esquemas MPEG-7. O futuro padrão MPE.G-2Í está sendo investigado como potencial tecnologia para representar esses novos requisitos multimídia como itens digitais universais. Os principais conceitos de consciência de contexto foram estendidos e adicionados à modelagem proposta também para prover personalização do ambiente. O conceito de perfil de aplicação interativa foi formalizado e discutido. Como forma de validação da proposta, uma aplicação de televisão Interativa f/ Y/) foi formalizada e apresentada como estudo de caso, possibilitando a discussão das limitações presentes na modelagem proposta. 1 Parto deste trabalho foi realizada nos laboratórios da T e l e com Italia Lab - T I L A B (que era c o n h e c i d o c o m o CSELT - Centro dl Studi e Laboratorio lelecommunicazioni), junto á Advanced Multimedia Division, em Turim, Itália, no período de maio a dezembro de 2001.<br>New forms of interaction became possible from the díssemiiiation of the interactive vídeo technology. The possibility for using multimédia objects in modem applications has proveu to be a bonus and the we want to provi de ways in which the user can internet with multimédia objects, while the presentation is occurring, with features that go beyond the regular controls of a VCR (Video-Cassette Recorder). Furthermore, the presentation of the video can be rnodified by events happening in the surrounding euvironment. ln this scenario, the environment may require the redesign of the user interface and the retargeting of the elementary streams parameters in order to match specific requirements and features of the environment (application, media, network and terminais). Several new techniques and standards have been produced in order to allow for the development of new applications; however, some potential new interaction forms are still unexplored. The main objective of this thesis is to present a proposal for Modelling of Context-Aware Interactive Environments Based on Standards of the MPEG (Moving Picture Expert Group) Family, using the UML (Uuified Modelling Lauguage) and considering the user actious from contextual information like a way to ease its interaction with interne tive applications. The 7vork desenhes a scenario for interactive applications, based on the emerging MPF1G-4 and MPEG-7 standards, that uses the context-awareness concepts in order to provi de the necessary support to the development of more interactive and usefid systems. At this point, new interaction cri teria have beeu established from distribution of MPEG-4 media objects and MPEG-7 scene descriptions on network environments. MPEG-21 is being studied for applying to new multimédia requirements, considering multimédia objects as universal digital item. Context-awareness aspects have been extended and added for providing persoualization ou the interactive environment. The concept of interactive application profile is formalized and presented. As validating mechanism, an ITV (Interactive Television) application is presented as a case of study, focalizing how and which kind of contextual information could be used in the ITV environment, allowing the discussion about the main problems of the proposed modelling.
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Zaib, Aneela Jahan. "Transcoding of MPEG-4 compressed video over error-prone channels." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63039.pdf.
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Chen, Li-Wei, and 陳立偉. "Efficient Bit Reservoir Design for MPEG Layer III, MPEG-4 AAC, and MPEG-4 HE-AAC." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/35596221703939464558.
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碩士<br>國立交通大學<br>資訊工程系所<br>93<br>Bit reservoir controlling the bits budget among music frames has been the kernel module to have good bits-quality tradeoff in current audio encoders like MPEG Layer III (MP3) and Advanced Audio Coding (AAC). The approaches of bit reservoirs can be investigated from demand-driven approach and budget-driven one. Demand-driven approach determines the required bits according to the audio contents while budget-driven one allocates bits according to the bit budgets accumulated in the bit reservoir. Existing bit reservoirs follow basically the budget-driven approach. This thesis presents an efficient bit reservoir design with concerns from both demand and budget. The bit reservoir includes a demand estimator to adaptively predict the bits required for each frame. Also, there is a budget regulator to control the bits used according to the codec protocol and the preferred scenario.
Furthermore, High efficiency AAC (HE-AAC) has included the Spectral Band Replication (SBR) in combination with AAC to achieve high audio quality at bit rates lower than 96 kbps. SBR reconstructs high frequency signal through replicating the low frequency parts. The bits allocated to AAC encoder module and SBR module decides the quality and compression efficiency. This thesis also extends the concept of bit reservoir to HE-AAC for efficient bits distribution between the AAC encoder and the SBR module. Both subjective and objective tests are conducted to verify the improved quality and efficiency of the new bit reservoir design.
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Yang, Jun-Rong, and 楊峻榮. "Implementing a MPEG-4 Interactive Environment with MPEG-J." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/37192909111617778943.
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碩士<br>國立成功大學<br>工程科學系專班<br>91<br>Although the interaction between end users and media can be implemented by the object-based MPEG-4 standard, it is still hard to make logic decisions and complex controls by using BIFS control parameters. MPEG-J extends the capabilities of MPEG-4 Version 2. It uses program controls to replace the mechanism of parameter control of MPEG-4 Version 1. It supplies many APIs that not only get a better performance of scenes’ interaction, but also can access the status of media player and control the resource usage of media player.
MPEG-J combines MPEG-4 stream media data with Java code which can make the stream data easily being used and developed across the different platforms such as PC, Set-Top-Box and PDA.
This thesis has implemented a MPEG-J player based on the principle and architecture of MPEG-J and MPEG-4 terminal architecture. MPEG-J programs embedded in MPEG-4 media stream, have also been created and run under the MPEG-J player to test different MPEG-J API applications in this work.
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Fan, Chen-Wei, and 范振韋. "MPEG-4 IPMPX Design and Implementation on MPEG-21 Testbed." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/dmng72.
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碩士<br>國立交通大學<br>電子工程系所<br>92<br>Distribution of digital media content is a trend in recent years. The issues of protecting the rights of digital content are thus becoming more and more important. In the thesis, the IPMPX system (Intellectual Property Management and Protection Extension system), a Digital Rights Management interface and architecture developed by MPEG is introduced and implemented. The goal of this thesis is to study the IPMP standard and design an MPEG-4 IPMPX system implementation on the MPEG-21 Multimedia Test Bed. MPEG-21 Test Bed is a part of MPEG standard for testing multimedia resource delivery. We integrate the MPEG-4 IPMP system into the MPEG-21 Testbed to perform the functions of IPMP such as en/decryption and watermarking. We design the software architecture of the IPMP system including its APIs. Furthermore, we design and implement an application example which uses the IPMPX system with MPEG-21 Test Bed to show its powerful functionalities. To match the other parts of the MEPG-21 Test Bed, the IPMP subsystem realization is written in C++. The IPMP subsystem together with the application example has been completed and described in this thesis.
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Chen, HongQuan. "Transcoding of MPEG-4 compressed video." Thesis, 2003. http://spectrum.library.concordia.ca/2404/1/MQ91009.pdf.
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MPEG-4 is an ISO/IEC standard, developed by the MPEG (Moving Picture Experts Group). The transmission of MPEG-4 compressed video over channels with different capacities may require a reduction in bit rate if the transmission media has a lower capacity than the capacity required by the bitstream. There are many different approaches to this problem of bit rate conversion. A feasible and effective method is transcoding. The emphasis in this thesis is on transcoding of MPEG-4 compressed video both in the pixel domain and in the DCT domain. In the pixel domain, (joint) transcoding of MPEG-4 compressed video with drift error correction is discussed in this thesis. In the DCT domain, a new DCT Coefficient Translation and Truncation Transformation Matrix (DCTTTM) based motion composition scheme is proposed, and several suboptimal approaches to reducing the computational complexity are discussed. In addition, frame-skipping transcoding of MPEG-4 compressed bitstreams in the DCT domain is addressed as well.
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Lin, Tsun-Fa, and 林春發. "TwinVQ in MPEG-4 Audio Coding." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/25835731237027664143.
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碩士<br>國立交通大學<br>資訊工程系<br>88<br>This thesis considers two issues of vector quantization (VQ) based on MEPG-4 TwinVQ. One is the robustness against channel noise; the other is the computational complexity of codebook search. Index assignment is a traditional method for VQ to improve robustness. This thesis considers the index assignment method based on MPEG-4. On the codebook search, two fast search algorithms for dynamic weighted VQ are proposed. The first algorithm is based on partial distortion search method (PDS) which searches entries in codebook by the partial distortion according to the associated weights. The second algorithm further reduces the computational complexity by obtaining the precise threshold to skip the candidates with the partial distortion. Simulation indicates that the first algorithm and the second algorithm reduce the complexity by 66 percent and 73 percent respectively without degrading the reconstructed quality.
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Lin, Ying-Jie, and 林英傑. "Cross Platform MPEG-4 Authoring System." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/27056665907217228866.
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碩士<br>臺中師範學院<br>教育測驗統計研究所<br>93<br>Personal Computers have already become many people’s essentials for daily life in these years. The incredibly fast development of Internet relatively increases the demands of multimedia applications. In addition, the progress of hardware equipments also pushes the development of multimedia, too. According to multimedia authoring, the methods for creating multimedia content are changing from segment-based authoring to scene-based authoring. Besides, non-interactive multimedia content is not enough for users in recent years. Users are desire to get more interactions with contents. Thus, the interactive content is going to be popular in the future.
Due to the future trend, this study develops a visual authoring system. People can use “drag-and-drop” to create multimedia content easily and quickly. The friendly user interface of this system also reduces the difficulty of setting the scene flows, interactions between users and contents and presenting orders of actors (such as sequence, parallel and so on) in authoring multimedia content.
This study uses MPEG-4 as the output format for the authoring system. Because MPEG-4 is objective and interactive, and it is a formal standard, MPEG-4 can satisfy the needs of this authoring system and can present all features this system has.
Moreover, this MPEG-4 authoring system can cross platforms and support handheld devices. These features may help the multimedia content created from this MPEG-4 authoring system be used widely.
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Tsai, Jang-Jer, and 蔡彰哲. "MPEG-4 Systems and Its Simulations." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/05018629723050251251.
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碩士<br>國立交通大學<br>電子工程系<br>87<br>MPEG-4 is the latest international standard for object-based multimedia application. MPEG-4 version 1 international standard was announced at April 1999. MPEG-4 Systems is the first part of the MPEG-4 specification. It defines how object-based multimedia components are combined together to form a complete yet flexible presentation.
My task can be divided into 3 phases: (1) what the standard is, (2) how it was implemented, and (3) how to construct test examples.
My first task is to study the MPEG-4 Systems. It contains roughly 7 parts: Systems decoder model, Object description framework, Scene description, Synchronization of elementary streams, Multiplexing of elementary streams, Syntactic description language, and Profiles.
My second task is to trace the MPEG-4 tools and players. The center of these programs is "the core code". It can be divided into 3 major parts: the core classes, the scene classes, and a general purpose template library - ZTL. There are three MPEG-4 players available; each of them consists of more than 100,000 lines of codes.
My last task is using the MPEG-4 tools and players to construct an example. Our testbed is a PC with Celeron 300 MHz processor running Microsoft windows 95/98/NT 4.0. In building our own example, we use 3D Studio Max to produce the prototype file, and make some necessary modifications to meet our own needs. Fighting against constant changes of MPEG-4 Software and ever-growing program bugs, we finally are able to demonstrate a 3-D object scene at the end.
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Wu, Min-Cheng, and 吳敏成. "MPEG-4 SLS Implementation and Improvement." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/bxukcr.
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碩士<br>國立臺北科技大學<br>資訊工程系研究所<br>97<br>To increase the efficiency of channel usage, the compressed audio techniques have been developed and improved in the past 20 years. After defining the successful MPEG-1 audio compression standards, the ISO/IEC MPEG Committee continued to develop the next generation MPEG-2 AAC (Advanced Audio Coding) standard in 1997. AAC is a big family of audio/speech coding technology. It has nine profiles to meet a variety of application scenarios. It has many different tools to meet the diversified requirements of both low-rate and high-rate transmission environments.
The SLS (Scalable to Lossless Coding) system is an extension of the previous MPEG-4 audio techniques. It is often built on the top of the AAC codec although its base-layer codec can be the other technology. Its name, Scalable to Lossless Coding, implies that it can produce a bit stream that achieves the lossless compression. However, if we extract a portion of this bit stream according to its syntax, we can play back a lossy version of the original audio. In other words, a single bit stream can provide decoded audios at various bit rates (and audio quality). In this study, we propose an implementation of SLS using an existing AAC codec. And then, we try to improve the SLS coding performance at low bit rates. Rearranging the MDCT coefficient priority in the SLS encoding (and decoding) process, we are able to achieve this goal with little computational overhead.
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Shih, Tse-Tsung. "MPEG-4 Part. 10 AVC Workload Characterization." 2004. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2807200420144400.
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Chin, Hao-Yun, and 秦浩雲. "Motion Estimation Engine for MPEG-4 Video." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/45059443697922758927.
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碩士<br>國立交通大學<br>電子工程系所<br>92<br>In this thesis, we propose the algorithms and associated architectures of motion estimation for MPEG-4 shape coding and texture coding.
The improvements on binary motion estimation (BME), the motion estimation of shape coding, are a penalty-free skipping algorithm that prevents redundant computations of SAD. According to simulation results, 11%–29% of SAD calculation are redundant and could be saved by the proposed algorithm at very little hardware cost. In addition, an optimal data storage scheme for alpha frame memory is proposed. First, a distributed tile-based memory organization is used to efficiently support the time-varying size of alpha plane. Second, a compression scheme is used to reduce the number of memory access and the size of the alpha frame memory. Under the criteria of MPEG-4 standard, the size of alpha frame memory can be reduced to 50% by introducing a small thumbnail buffer (2.73%–5.08% of the original frame memory size). The proposed techniques for BME are all lossless. Thus, the picture quality of encoded video is maintained. A reference implementation for BME supporting CP@Lv2 (11880BAB/s) is synthesized to operate at 12.6 MHz, and has the gate count of gates.
This thesis also presents a new pixel decimation-based search algorithm for motion estimation of texture coding. The proposed quartet-pel motion estimation (QME) search algorithm reduces the number of pixels taken into account for the cost function of the matching criteria at every search point, therefore reduces the computational complexity and the required memory bandwidth. Furthermore, the proposed algorithm has a regular data flow, which in turn leads to hardware-efficient implementations. Simulation results show that QME achieves almost the same coding performance as full-search block matching algorithm (full-search BMA) in terms of PSNR and the size of the coded bit stream. A configurable parameter of candidate numbers can be adjusted in trade-off between coding performance and processing time. The synthesized circuit of QME can support ASP@Lv5 (48,600MB/s, 720x576) at 19.9MHz and can operate at a maximum speed of 83.3MHz. The gate count is 115,268 synthesized under 20MHz constraint. The average power consumption is 47.64 mW, estimated by Synopsys PrimePower with random inputs. The energy for the processing of a MV is 0.871μJ. The encoded video quality is close to that of full-search BMA, with a maximum PSNR drop of 0.0011 dB and 1.03% of increment in encoded bit-stream size.
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WU, CHENG-LIN, and 吳政霖. "The Research of MPEG-4 Multicast Technique." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/74627133734407506709.
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碩士<br>國立臺灣科技大學<br>資訊工程系<br>92<br>Video streaming over the internet is becoming very popular and it competes with traditional TCP based applications for bandwidth utilization. In this paper, network stability and resource utilization fairness become critical issues. To solve these problems source rate control and adaptation should be introduced for UDP-based traffic to become TCP-friendly. We propose an adaptive streaming framework for multicast streams over TCP/IP networks. Based on Audio-Visual Content (AVOs) classification and network congestion feedbacks, the video server can use these characters dynamically adds and drops MPEG-4 AVO for every receiver to conform to SMCC (Smooth Multirate Multicast Congestion Control) mechanism and adapt to current network situation.
The MPEG-4 video encoded by FGS (Fine Granularity Scalability) mechanism generates two layers. One of these two layers is base layer and the other one is enhancement layer. Base layer’s priority is higher than enhancement layer. So we provide better service for base layer by using differential service.
Because of the packet loss caused by network congestion, we use FEC (Forward Error Correction) to protect the important data. We give the frames that have higher priority more FEC protection and give lower priority’s frames less protection. By using FEC, we still have chance to decode complete frames when packet loss happens.
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"Error-resilient coding tools in MPEG-4." 1998. http://library.cuhk.edu.hk/record=b5889563.
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by Cheng Shu Ling.<br>Thesis submitted in: July 1997.<br>Thesis (M.Phil.)--Chinese University of Hong Kong, 1998.<br>Includes bibliographical references (leaves 70-71).<br>Abstract also in Chinese.<br>Chapter Chapter 1 --- Introduction --- p.1<br>Chapter 1.1 --- Image Coding Standard: JPEG --- p.1<br>Chapter 1.2 --- Video Coding Standard: MPEG --- p.6<br>Chapter 1.2.1 --- MPEG history --- p.6<br>Chapter 1.2.2 --- MPEG video compression algorithm overview --- p.8<br>Chapter 1.2.3 --- More MPEG features --- p.10<br>Chapter 1.3 --- Summary --- p.17<br>Chapter Chapter 2 --- Error Resiliency --- p.18<br>Chapter 2.1 --- Introduction --- p.18<br>Chapter 2.2 --- Traditional approaches --- p.19<br>Chapter 2.2.1 --- Channel coding --- p.19<br>Chapter 2.2.2 --- ARQ --- p.20<br>Chapter 2.2.3 --- Multi-layer coding --- p.20<br>Chapter 2.2.4 --- Error Concealment --- p.20<br>Chapter 2.3 --- MPEG-4 work on error resilience --- p.21<br>Chapter 2.3.1 --- Resynchronization --- p.21<br>Chapter 2.3.2 --- Data Recovery --- p.25<br>Chapter 2.3.3 --- Error Concealment --- p.28<br>Chapter 2.4 --- Summary --- p.29<br>Chapter Chapter 3 --- Fixed length codes --- p.30<br>Chapter 3.1 --- Introduction --- p.30<br>Chapter 3.2 --- Tunstall code --- p.31<br>Chapter 3.3 --- Lempel-Ziv code --- p.34<br>Chapter 3.3.1 --- LZ-77 --- p.35<br>Chapter 3.3.2 --- LZ-78 --- p.36<br>Chapter 3.4 --- Simulation --- p.38<br>Chapter 3.4.1 --- Experiment Setup --- p.38<br>Chapter 3.4.2 --- Results --- p.39<br>Chapter 3.4.3 --- Concluding Remarks --- p.42<br>Chapter Chapter 4 --- Self-Synchronizable codes --- p.44<br>Chapter 4.1 --- Introduction --- p.44<br>Chapter 4.2 --- Scholtz synchronizable code --- p.45<br>Chapter 4.2.1 --- Definition --- p.45<br>Chapter 4.2.2 --- Construction procedure --- p.45<br>Chapter 4.2.3 --- Synchronizer --- p.48<br>Chapter 4.2.4 --- Effects of errors --- p.51<br>Chapter 4.3 --- Simulation --- p.52<br>Chapter 4.3.1 --- Experiment Setup --- p.52<br>Chapter 4.3.2 --- Results --- p.56<br>Chapter 4.4 --- Concluding Remarks --- p.68<br>Chapter Chapter 5 --- Conclusions --- p.69<br>References --- p.70
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Wang, Chau-Jia, and 王朝嘉. "A Study of MPEG-4 ALS Encoding." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/wcc7hb.
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碩士<br>國立臺北科技大學<br>資訊工程系研究所<br>99<br>In this thesis, we study the features of MPEG-4 ALS encoder, the optimal encoder is not public, and it can quickly estimate an optimal order for each blocks, so we try to guess the method of the optimal encoder.
First, we test the features of encoder and transients for the choice of block switch level, then experiment the different between pop music and classical music. Furthermore, in order to reduce quantization error, we implement a method, on the other hand, according to the optimization theory, we try to find the best quantization step, to improve the encoding effect. Finally, we found “Least Square method” on digital signal processing books, it can also result the linear prediction coefficients, so we implement it to compare with Levinson-Durbin for residual energy and residual encoded bits, and discuss whether it suits this system.
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Yi, Chiang Yen, and 江衍毅. "An Efficient MPEG-4 Texture Coding Algorithm." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/48495886966280809321.
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碩士<br>中華大學<br>資訊工程學系碩士班<br>93<br>In this paper, the directional SA-DCT (DSA-DCT) and modified boundary block merging (MBBM) algorithms are proposed for coding arbitrarily shaped video objects. DSA-DCT reorders the object pixels within a boundary block according to the edge direction of the binary shape information of the boundary block. As a result, the AC coefficients after performing SA-DCT on the reordered block will be small. Therefore, the computational complexity and the bit rate required to represent the reordered boundary block can be reduced. MBBM is a modified version of BBM, which takes into account only horizontal and vertical merging since diagonal merging occurs rarely and does not guarantee to get better performance. Modified SA-DCT is than exploited to encode each horizontally or vertically merged block. In addition, the MBBM-DSA-DCT algorithm which exploits the merits of DSA-DCT and MBBM is proposed to improve the coding performance. To further improve the coding performance, the DC-DSA-DCT and DC-MBBM-DSA-DCT algorithms which incorporate the merit of DC-SA-DCT into DSA-DCT and MBBM-DSA-DCT are proposed. Experimental results have shown the effectiveness of the proposed techniques.
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Shih, Tse-Tsung, and 施澤聰. "MPEG-4 Part.10 AVC Workload Characterization." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/60928883239764894345.
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碩士<br>國立臺灣大學<br>資訊工程學研究所<br>92<br>Multimedia applications have become important workloads for modern computer systems. The latest video coding standard H.264/AVC adopts lots of coding tools, which can improve the coding efficiency and visual quality but also add the implementation complexity a lot. The increasing computation and storage requirements pose challenges to achieve real-time video playback on general-purpose processors (GPPs). In this thesis, I study and analyze the performance of a software implementation of H.264/AVC decoder on GPPs. Through this study, we can find out the performance bottleneck of running the H.264 decoder on a modern GPP. Understanding the characteristics of H.264 decoder allows us to tune hardware processor architecture and software program implementation for performance. I analyze three important program characteristics: the intrinsic available ILP, program locality and control flow predictability. Furthermore, I investigate what application features (sequence content, resolution, bitrate) and new added coding tools (multi-ref frames, CABAC) have direct impact on performance. In this study, I adopt the simulation-based approach to perform workload characterization. It allows us to explore the design space thoroughly and evaluate different architectural enhancements. The important findings of this study includes 1) H.264 decoder does present significant instruction level parallelism. 2) H.264 is computation-bound not memory-bound because block-level data reuse can be captured by data cache. 3) H.264 has poor branch predictability due to nested loops and content dependent branch. Loop unrolling and absolute instruction can reduce branch stall time significantly. 4) For application features, video contents with low motion and smaller resolution increase the inter frame prediction opportunity thereby increasing cache miss rates. Higher bitrate increases execution time of entropy coding. New added multi-ref frame does not have direct impact on cache performance since inter-frame reuse cannot be captured in data cache. CABAC has lower control flow predictability than CAVLC due to bit-wise access to bitstream.
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Chen, Wei-Tao, and 陳維濤. "Computational power sensitive MPEG-4 AVC encoder." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/73257046734952536020.
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碩士<br>國立成功大學<br>資訊工程學系碩博士班<br>92<br>Better Audio-Video compression quality is achieved with the progress of new standards. As we know, the better compression ratio, the more computation complexity we need. AVC Encoder has many times complexity than other encoders before to achieve better compression performance. The huge computation complexity limits its practical applications. Therefore, we want to control the encoder to achieve better quality with limited computation power of the available computer.
Similar to previous encoders, most computation power of AVC encoder is spent on “Motion Estimation”. Therefore, we control the computation complexity of AVC encoder through controlling “Motion Estimation” part. In this paper, we not only modify the coding procedure to improve the performance of AVC Encoder, but also design an algorithm that allocates the available computing power to different coding functions under a preset frame-rate. Computer Simulations are presented for various standard test sequences to show the effect of the algorithms proposed in this thesis.
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Tong, Kin-Lam, and 唐健霖. "An Implementation of MPEG-4 IPMP System." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/60207328568368333953.
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碩士<br>國立交通大學<br>電子工程系<br>91<br>With the widespread of Internet, electronic commercial activities involving the trade of digital multimedia contents over network is getting popular. Therefore, Intellectual Property Management and Protection (IPMP), which protects IP and enables convenient IP trading of contents, becomes an indispensable element of an e-commerce system.
MPEG started a standardization effort on specifying a common interface/protocol for IPMP in 1997. They integrate IPMP systems into the existing MPEG multimedia standards. Up to now, IPMP specifications for MPEG-4 and MPEG-2 are nearly completed. The MPEG committee is currently working on MPEG-21 IPMP.
The goal of this thesis is to study the MPEG-4 IPMP standards and then design and implement an MPEG-4 IPMP application system. The MPEG-4 IPMP system is a message-based system. Tools such as encryption algorithms developed by different companies or entities can communicate with each other through the use of common message exchange protocol. We thus like to develop application examples that can demonstrate the functionality and powerfulness of this standard. This thesis can roughly be divided into three parts. The first part describes the concept, architecture and interfaces of MPEG-4 IPMP. In the second part, we collect, trace and integrate the software tools that can be used for constructing IPMP application systems. Finally, several application examples have been designed and implemented.
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Ma, Shyh-Yih, and 馬仕毅. "Video Processing for MPEG-4 Encoding Systems." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/14127110273531076387.
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博士<br>國立臺灣大學<br>電機工程學研究所<br>89<br>Abstract
This dissertation presents three video processing techniques that are essential for real-time MPEG-4 encoding systems.
The content-based interactivity is one of the most important features of the MPEG-4 visual coding; however, the automatic generation of the shape information is still an open research problem. In the first part of this dissertation, an efficient moving object segmentation is proposed to automatically generate the shape information. Background registration technique is used in this method to construct a reliable background image from the accumulated frame difference information. The moving object region is then separated from the background region by comparing the current frame with the constructed background image. Finally, a post-processing step is applied on the obtained object mask to remove noise regions and to smooth the object boundary. In situations where object shadows appear in the background region, a pre-processing gradient filter is applied on the input image to reduce the shadow effect. Very good segmentation quality and high execution speed are demonstrated by the experimental results. This algorithm is very suitable for real-time MPEG-4 VOP generation.
The motion estimation is always the most computationally intensive part of a video encoding system. In the second part of the dissertation, an efficient motion estimation algorithm for real-time implementations of MPEG-4 encoder on multimedia processors is presented. The motion vector predictor position is used as the starting point in the search process because the correlation between neighboring motion vectors is strong. The line search pattern is used in the proposed algorithm to reduce the memory access as well as to exploit the special multimedia processor instructions for SAD calculations. Experimental results show that the performance of the proposed predictive line search (PLS) is very close to the full search algorithm. Compared with the well-known diamond search fast algorithm, the predictive line search shows better performance and robustness especially for high motion sequences.
In order to exploit the concept of system-on-a-chip, a CMOS active pixel sensor (APS) camera chip with direct frame difference output is reported in the last part of the dissertation. This chip combines an important signal processing for video segmentation with the image sensing circuit to form a smart camera system. The proposed APS cell circuit has in-pixel storage for previous frame image data so that the current frame image and the previous frame image can be read out simultaneously in differential mode. The signal swing of the pixel circuit is maximized for low supply voltage operation. Good image quality and correct signal processing results can be obtained from the experimental results.
These techniques can greatly help the design and implementation of real-time MPEG-4 applications.
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Lei, Chao-Sheng, and 雷朝聖. "The VLC encoder/decoder for MPEG-4." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/79750329993411057859.
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碩士<br>南台科技大學<br>電子工程系<br>92<br>The representation of audio, image and video signals involves a vast amount of data, so signal compression is indispensable. Recently, variable length code (VLC) has been widely used in multimedia and lossless coding compression such as JPEG and MPEG. This thesis describes an efficient class-based VLC encoder/decoder and its VLSI architecture for MPEG-4. It takes advantage of logic optimization techniques, and achieves high throughput. The computation complexity of the proposed VLC is quite low and its memory requirement is small. Hence, it is easily implemented by VLSI and very suitable for real-time MPEG-4 applications.
The VLC architecture has been synthesized on Synopsys Design Compiler with the standard-cell from TSMC 0.35-μm cell library. Finally, the layout for the design was generated with the Avant! tools, Apollo (for floorplan, placement and routing). The gate counts and core size of VLC encoder/decoder are 9624/9486 and / , respectively. In the simulation, it’s clock frequency achieves 50MHz.
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Hsiao, Po-Kang, and 蕭伯剛. "An MPEG-4 Scalable Video Streaming Platform." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/21434608962987963804.
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碩士<br>國立臺灣大學<br>資訊工程學研究所<br>90<br>Nowadays, streaming video over heterogeneous network is ready to take off since the scalable video coding techniques and the underlying network infrastructure have been matured and fully established. However, the streaming server’s support for scalable video is not prevailing. The problems arisen from dealing with the scalable video codecs are bandwidth allocation and QoS guarantee between different layers in end-to-end transmission. We propose a decoding tree concept to assist the decision of bandwidth allocation and scheduling, and a hybrid TCP/UDP transport scheme to conquer the QoS guarantee problem, respectively.
In addition to the support for scalable video streaming, it is also highly desirable that the multimedia-streaming systems provide full VCR functionality to support effective and fast browsing. We provide a coarse-precision solution by seeking to the nearest I-frame and frame dropping.
As for the system implementation, we design a streaming platform based on the specification of MPEG-4 part 8, “MPEG-4 over IP”. We pack the scalable video bitstreams into the standard MP4 container, and design our own session control, multiplexing control and transport control protocols. With the streaming server, player and the mechanisms to support scalable video streaming and VCR functionality, a complete MPEG-4 scalable video streaming platform is built.
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Lu, Chia-Hsien, and 呂家賢. "An Implementation of MPEG-21 IPMP and REL with MPEG-4 IPMPX Framework." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/32104621836942773519.
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碩士<br>國立交通大學<br>電子工程系所<br>94<br>As the network and digital media technologies advance, it is easy nowadays for everyone to create and distribute digital multimedia contents. How to effectively manage and protect the digital content becomes an important issue. In this thesis, the technologies of MPEG-21 IPMP (Intellectual Property Management and Protection) and REL (Rights Expression Language) are adopted to construct a DRM system. The MPEG-4 IPMPX (Intellectual Property Management and Protection Extension) system is also used as a basic framework for our implementation.
To simulate a real-time streaming system, we use the MPEG-21 Testbed as our multimedia delivery platform, which is part 13 of the MPEG-21 standard for testing the multimedia resource delivery. The MPEG-21 IPMP provides ways to protect a DIDL element. The MPEG-21 REL is able to describe various kinds of rights and it provides an authorization model to generate an authorization proof to manage the rights. To implement these standard specifications, we design a set of IPMP Tools, which owns the functionalities of the MPEG-21 IPMP and REL, and we integrate this set of tools into the MPEG-4 IPMPX framework on the MPEG-21 Test Bed. Through the IPMP Message exchange mechanism, an IPMP Tool can request an authorization proof to check if the data processing is permitted.
In order to deliver digital contents securely, we encrypt digital contents by using a server-side encryption Tool. To ensure the security of delivering decryption keys, we propose a content protection mechanism with a key management mechanism. In this mechanism, we design a key server that manages decryption keys and sends encrypted decryption keys to the client. At the end, we develop three application examples to demonstrate that our system can successfully safeguard digital resources and effectively manage the rights.
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Chiou, Ting, and 邱挺. "Design of Psychoacoustic Model for MPEG-4 Advanced Audio Coding and MPEG Layer III." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/79802118166897424790.
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碩士<br>國立交通大學<br>資訊工程系所<br>92<br>This thesis presents an efficient psychoacoustic model providing better quality than the psychoacoustic model II. This thesis considers the design of the psychoacoustic models from two aspects. First, we improve the psychoacoustic model from the aspect of varying tonal and noise masking offset with bands and energy normalization to suppress the distortion, which is called the fishy noise or the birdie noise, caused by the overestimated masking in the harmonic-rich signals. Second, we consider the design issue in implementing the psychoacoustic model in the filterbank used in MP3 and AAC instead of the independent FFT to reduce the computing complexity and storage. The efficient psychoacoustic model provides 60 percentage performance gain compared to the psychoacoustic model II in MPEG-2/4 AAC and MP3. For the quality comparison based on Objective Difference Grade (ODG) and the subjective test, the efficient psychoacoustic model provides quality gain of 0.26 at 128k bit rates and 0.3 at 112k bit rate for MPEG testing bitstream in NCTU-AAC.
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Lin, Yi-Kai, and 林義凱. "VLSI design of a Robust Tri-mode MPEG-2/MPEG-4/XviD Video Decoder." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/15368238933408576124.
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碩士<br>國立成功大學<br>資訊工程學系碩博士班<br>94<br>The technology behind the MPEG-2 and the MPEG-4/XviD shows us some similar skills, including IDCT, de-quantization, variable length coding, motion vector, as well as macro block involving two modes, intra and inter (non-intra). Setting up the
correct parameter for each decoding process, the decoder will run the control path and finish decoding process depends on the input bit-stream data after we merge these two decoding functional unit for the largest efficient.
In order to prevent decoding process crashing, it must employ some constrained rules and skills, the range of the values after de-quantization, the error detection of the variable length coding and the validation of motion vectors. We implement the error handler reach the goal for decoding overall input bit-stream data and see what it decoded.
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Leupold, Jan [Verfasser]. "MPEG-4-Szenenbeschreibung in Telepräsenz-Szenarien / Jan Leupold." 2008. http://d-nb.info/989934675/34.
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Yunhsuan, Lee, and 李韻玄. "A Design of Adaptive Rate MPEG-4 Player." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/82152157746235317036.
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碩士<br>國立海洋大學<br>資訊科學學系<br>90<br>With the evolutions of multimedia technology and the release of image compression standards (MPEG-1/2/4), high—quality multi-media products are widespread gradually. People are getting used to the applications of digital multi-media. But the most common way is to save the data in the media and to play it on the computer or player later.
On the era of Internet, another more attractive solution is the streaming server. Instead of downloading the whole content, users watch the content during the downloading, which not only saves the time and space, but also provides the capabilities for the interactive playing.
The quality of streaming multi-media depends on the quality of networks and also the client’s decoding power. In our research, we assume that the Internet already provides sufficient quality for the streaming, and the client uses its CPU to perform the decoding, which is a common situation in the lower-end embedded system. Our experiment shows that if the client cannot provide enough CPU resource to decode all the picture frames it received, some frames are dropped and others might get blurred due to the reference relationship between frames. A monitor mechanism was proposed to actively notify the server so that the server can dynamically adjust the frame rate up and down. On the other hand, users can decide the playing quality themselves, which bypassed the automatic adjustment.
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Huang, Yang-Chih, and 黃揚智. "A Study on Interactive Support of MPEG-4." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/79940370599963039256.
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碩士<br>國立交通大學<br>電子工程系<br>88<br>The MPEG-4 standard adopts an object-based audiovisual representation model with hyperlinking and interaction capabilities and it supports both natural and synthetic content. It is expected that this standard will become the information coding playground for future multimedia applications. MPEG-4 meets the needs of application fields such as video on the Internet, multimedia broadcasting, content-based audiovisual database access, games, advanced audiovisual communications over mobile networks, tele-shopping, and remote monitoring and control. A major difference with previous audiovisual standards is the object-based audiovisual representation model that builds the foundation of MPEG-4. An object-based scene is built using individual objects that have relationships in space and time, allowing harmonious integration of different types of data into one scene.
The goal of this thesis is to study and simulate the MPEG-4 Systems specifications. Particularly, we focus on the interactive features of the MPEG-4 standard. Three tasks are involved in this thesis. The first task is to study the MPEG-4 Systems specification, especially on scene description and its interactive support. Secondly, we trace and build the MPEG-4 authoring tools and players. The final task is using the MPEG-4 authoring tools to construct interactive scenes to demonstrate the MPEG-4 interactive capabilities. Although MPEG-4 standard committee provides some basic tools for simulating the MPEG-4 systems, these tools and players are not bugs-free. Moreover, the source codes of players are very huge, each of them consists of more than 100,000 lines of C++ code. We struggle to trace and modify these source codes and finally using them to construct demonstration examples successfully at the end. In the meanwhile, we also report several vital bugs in the standard software to the IM1 group.
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YI, Tsai PO, and 蔡柏義. "Integrated MPEG-4 and Digital Video/Audio Storage." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/01808201149026397512.
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碩士<br>國立臺灣科技大學<br>電子工程系<br>93<br>The digital video is popular on the market for the applications. Base on the digital Video is batter than traditional analog video from quality, reliability and available …etc. The digital video have many advantage such as video appreciation、storage and control interface all of the different traditional analog video.
The ISO MPEG committee, after successful completion of the MPEG-1 and the MPEG-2 standards is currently working on MPEG-4, the third MPEG standard. Originally, MPEG-4 was conceived to be a standard for coding of limited complexity audio-visual scenes at very low bit-rates. One of the key functionalities supported by MPEG-4 is robustness in error prone environments. In general, the MPEG-4 standard provides solutions for coding of natural or synthetic video and audio, as well as a system for multiplex/de-multiplex and description of scenes in a truly flexible manner. In the applications they are very extensive of the potential such as IP camera、PDA/GSM、Media center、Video capture and surveillance systems…etc.
The paper integrated on MPEG4 compression, the technology focus on the video、image、audio and voice. The system input is TV decoder; we can playback on the TFT-LCD or TV. The paper includes video/audio capture, the storage by hard disk. We believe that applications will develop on the network and video for future.