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Transform and embedded coding techniques for maximum efficiency and random accessibility in 3-D scalable compression

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2005年第10期14卷 1632-1646页

作者： Leung, R Taubman, D Univ New S Wales Sch Elect Engn & Telecommun Sydney NSW 2052 Australia

This study investigates random accessibility and efficiency enhancements in highly scalable video and volumetric compression. With the advent of interactive multimedia technology, random accessibility has emerged as an increasingly important consideration in the design and optimization process. In this paper, we assess the impact that the transform, embedded coding components, and code-block configurations have on the compression efficiency and accessibility of a scalable codestream. We develop performance bounds on techniques which exploit temporal redundancy within the confines of a feed-forward compression system. We also examine their random access properties to argue the significance of motion-adaptive subband transforms. When information-theoretic measures are used to determine the potential benefits of three-dimensional (3-D) context coding, we find that most of the coding gain is attributed to code-block extension, rather than interstice context modeling itself. To gain further insight into the tradeoffs that the coding part has to offer, we run a series of simulations to determine code-block partitioning strategies which maximize reconstruction quality and space-time localization. The LIMAT framework and EBCOT coding paradigm have laid a solid foundation for further progress in the development of highly scalable 3-D compression systems.

关键词： coding efficiency context modeling motion-adaptive transform random accessibility scalable compression

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An improved spatio-temporal-SNR FGS video coding scheme using motion compensation on enhancement layers

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Journal of Shanghai University(English Edition) 2006年第4期10卷 325-329页

作者：江涛张兆杨马然石旭利 School of Communication and Information Engineering Shanghai University Shanghai 200072 P.R. China

In this paper an effective MC ＋ FGSST structure is explored, which is appropriate for scalable video coding. The structure obtains spatio-temporal-SNR fine granular scalability, and achieves high coding efficiency at the same time. Users can acquire their necessary scalability by choosing and combining them. Then, a high-powered codec solution based on this structure is presented. Subsequently, a focus issue on the right number of bit-planes should be used for motion compensation is discussed, and an algorithm is presented for this issue. The proposed codec saves a lot of hardware expense. Simulation results indicate that the performance of MC ＋ FGSST structure is superior to that of FGSST structure.

关键词： fine granularity scalability （FGS） coding efficiency motion compensation spatio-temporal scalability.

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Efficient audio coding with optimized subband configurations

Efficient audio coding with optimized subband configurations

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Workshop on Applications of Signal Processing to Audio and Acoustics

作者： Ali, MT Mian, MS Univ Engn & Technol Dept Elect Engn Lahore Pakistan

ISBN: (纸本)0780391543

A dynamic subbands design selection scheme for perceptual audio coding is presented which optimizes the coding efficiency in association with all improved utilization of the masking potential of the signal. The choices for subbands design Selection include critical hands, uniform subbands, uniform subbands with a non-uniform last hand and a non-uniform-non-critical (NUNC) subbands distribution. A particular consideration is given to corresponding critical band boundaries while formulating NUNC subbands, to minimize the perception of coding noise. The design selection decision is made by First identifying the best tradeoff between empty quantizer slots and amount of side information, followed by a minimization or the perceptual entropy (PE) estimates. A further analysis is carried Out to identify the prominent spectral peaks (PSPs), with a view to efficiently utilize their masking potential by the bit allocation algorithm which makes a bit cut first to subbands with PSPs. Test results based oil ITU-R recommendation BS.1 116 show that Our coding scheme performs slightly better as compared to MPEG-4 AAC verification model (V-M) for a majority of signal types from the SQAM database. The paper Concludes with a discussion Of future research implications of the work.

关键词： audio coding entropy ITU-R recommendation BS.1116 MPEG-4 AAC verification model SQAM database bit allocation algorithm coding efficiency coding noise critical bands dynamic subbands design selection scheme nonuniform last band nonuniform-noncritical subb Audio coding Subbands Allocation Algorithm critical band entropy code efficiency side information

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Packet loss concealment in predictive audio coding

Packet loss concealment in predictive audio coding

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Workshop on Applications of Signal Processing to Audio and Acoustics

作者： Wabnik, S Schuller, G Hirschfeld, J Kraemer, U Fraunhofer Inst Digital Media Technol D-98693 Ilmenau Germany

ISBN: (纸本)0780391543

In this paper we present and evaluate Several concealment strategies for packet losses in the context of it low delay predictive audio coder. Our goal is to minimize the audible impact of a packet loss. The problem is that the Predictive coder is backward adaptive, hence depending on past values. There is a predictor reset, but to increase coding efficiency. the distance between two resets is several hundred packets. Hence, not only the lost packet itself cannot be reconstructed, but the transmitted data LIP to the next reset does not result in an exact reconstruction of the audio signal. Our approach is to try to use its much information as possible from the still available data until the next reset. and to reconstruct an audio signal such that distortions are least objectionable. To compare different approaches, we conducted it listening test. The result is that an adaptive reconstruction filter works best in this context.

关键词： audio coding adaptive reconstruction filter audible impact audio signal coding efficiency packet loss concealment packet losses predictive audio coding Packet loss Audio coding audio signals code efficiency audio coder Data Security

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Generalized theory of hunting-free framing codes for digital transmission and multiplexing

Generalized theory of hunting-free framing codes for digital...

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9th World Multi-Conference on Systemics, Cybernetics and Informatics

作者： Takasaki, Yoshitaka Toyo Univ Dept Elect & Elect Engn Kawagoe Saitama 3508585 Japan

ISBN: (纸本)9789806560543

Generalized theory of hunting-free framing codes is invesigated as extentions of previous results based on multipled block codes (MBCs). First, the principles of MBC based codes are overviewed to show their capacities for realizing hunting-free reframing. Then it is shown that modification of above codes can be used for obtaining more generalized version of code formats. Finally, optimization and comparison of efficiencies of generalized hunting-free framing codes are investigated to show their improved efficiencies.

关键词： digital transmission framing hunting-free fi-aming generalized codes coding efficiency

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Automatic speech decomposition and speech coding using MDCT-based hidden Markov chain and wavelet-based hidden Markov tree models

Automatic speech decomposition and speech coding using MDCT-...

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Workshop on Applications of Signal Processing to Audio and Acoustics

作者： Tantibundhit, C Boston, JR Li, CC El-Jaroudi, A Univ Pittsburgh Dept Elect & Comp Engn Pittsburgh PA 15261 USA

ISBN: (纸本)0780391543

Speech is decomposed into three different components. based on the idea of Daudet and Torresani (Signal Processing, vol. 82, no. 11, pp. 1595, 2002), as signal = tonal + transient + residual. The tonal and transient components identified using a small number of coefficients of the modified discrete cosine transform (.MDCT.) and the wavelet transform, respectively. Determinations of the significant MDCT and wavelet coefficients in the algorithm of Daudet and Torresani, referred as the D&T algorithm, ire achieved by thresholds. All MDCT coefficients are assumed to be independent as well as wavelet coefficients. However, the MDCT coefficients probably have statistical dependencies, namely the clustering, and persistence properties, and so do the wavelet coefficients. We propose a modification to the D&T algorithm, that can capture statistical dependencies by utilizing the hidden Markov model. The Viterbi and the Maximum a Posteriori (MAP) algorithms, used to find file optimal state distribution, are applied to determine the significant MDCT and wavelet coefficients automatically. The modified algorithm was used to encode 43 monosyllabic Consonant-Vowel-Consonant (CVC) words and 3 sentences. Results showed that the modified algorithm improves the coding efficiency by 37% compared with the threshold method of D&T algorithm when equal numbers of significant coefficients;are used.

关键词： discrete cosine transforms hidden Markov models maximum likelihood estimation speech coding trees (mathematics) wavelet transforms MAP algorithms Viterbi algorithms automatic speech decomposition clustering properties coding efficiency hidden Markov chai speech coding Hidden Markov models Viterbi algorithm mdct(modified discrete cosine transform) discrete cosine transforms wavelet transforms Wavelet coefficients maximum likelihood estimation code efficiency Markov chain algorithms THRESHOLDING METHOD

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Improving coding efficiency in grid-based hybrid video coding schemes

Improving coding efficiency in grid-based hybrid video codin...

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IEEE International Conference on Acoustics, Speech, and Signal Processing

作者： Heising, G Heinrich Hertz Inst Nachrichtentech Berlin GmbH Image Proc Dept D-10587 Berlin Germany

ISBN: (纸本)0780374029

In the past many grid-based video coding schemes using image warping prediction have been proposed. The advantage of grid-based motion compensation is its ability to model nontranslational motion. Disadvantages are the interdependency of motion vectors which require more complex motion estimation strategies and its restricted ability to model motion boundaries. In this paper different solutions to cope with the latter deficiency are presented and compared with respect to coding efficiency, In particular, three adaptive modes for handling motion discontinuities and a block-adaptive loop filtering are presented. It is shown that these are key components for achieving a high coding gain in grid-based hybrid coding. Introducing these features into a wavelet-based video coder leads to a coding gain of up to 2,5 dB compared to ITU H263+ and MPEG-4.

关键词： video coding transform coding motion compensation motion estimation adaptive filters coding efficiency grid-based video coding hybrid video coding image warping prediction motion compensation motion estimation block-adaptive filtering loop filtering wavelet-based coder coding gain ITU H.263+ MPEG-4

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coding efficiency of multi-ring and single-ring differential chain coding for telewriting application

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IEE PROCEEDINGS-VISION IMAGE AND SIGNAL PROCESSING 2001年第4期148卷 241-247页

作者： Andrieux, J Seni, G Eurecom Inst F-06904 Sophia Antipolis France Motorola Inc Human Interface Labs Palo Alto CA 94304 USA

The recent availability of small personal digital assistants (PDAs) with a touchscreen and communication capabilities has been an influential factor in the renewed interest in telewriting, a technique for the exchange of handwritten information through telecommunications means. In this context, differential chain coding algorithms for compression of the handwritten ink are revisited. In particular, it is shown that the coding efficiency of multi-ring differential chain coding (MRDCC) is not always better when compared to single ring differential chain coding (DCC), as previously suggested. These, algorithms were tested on over 300 handwritten messages using a relative compactness criterion and a per-length distortion measure. The probabilities of relative vectors in MRDCC and DCC are related, an expression for relative compactness in the MRDCC case is introduced, and the application of Freeman's criteria for the selection of the appropriate code for a family of curves is illustrated.

关键词： .rings ink quantisation chain codes coding efficiency single-ring

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Application of multipled block codes to hunting-free reframing and asynchronous multiplexing

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IEICE TRANSACTIONS ON COMMUNICATIONS 2004年第11期E87B卷 3187-3194页

作者： Yoshida, H Takasaki, Y Toyo Univ Grad Sch Engn Kawagoe 3508585 Japan

\Application of multipled block codes (MBCs) for realizing new flexible and efficient transmission systems that feature in huntingfree reframing and asynchronous multiplexing is investigated. First, the principles of MBC are overviewed to show the capacities of filterless clock recovery. Then it is shown that modification of simple frame structure of MBC line code can be used for attaining hunting-free reframing for multiplexing systems. Two types of MBCs are developed to this end. While the one uses header blocks for hunting-free reframing, the other uses distributed frame patterns. Header design of multipled block codes (MBC) for hunting-free reframing (HFR) is investigated for frame patterns with and without violation compensation. The feasibility of hunting-free reframing is tested in an experimental system. Application of hunting-free reframing to asynchronous multiplexing is also investigated and tested in an experimental system. Finally, advantages of hunting-free multiplexing systems are discussed.

关键词： multipled block codes hunting-free reframing header type frame asynchronous multiplexing coding efficiency

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RNS-based implementation of 8x8 point 2D-DCT over field-programmable devices

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ELECTRONICS LETTERS 2003年第1期39卷 21-23页

作者： Fernández, PG Lloris, A Dept Electron & Tecnol Computadores Granada 18071 Spain

A new implementation of an 8 x 8 two-dimensional discrete cosine transform (2D-DCT) processor based on the residue number system (RNS) is presented. This architecture makes use of a fast cosine transform algorithm. It is shown that the RNS implementation of the 2D-DCT over field-programmable logic devices leads to a 129% throughput improvement over the equivalent binary system.

关键词： residue number systems discrete cosine transforms image coding data compression pipeline arithmetic field programmable gate arrays RNS-based implementation 2D-DCT image compression coding efficiency pipelined architecture field-programmabl Image compression discrete cosine transforms residue number systems image coding pipeline arithmetic Field programmable gate arrays Data compression code efficiency

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