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International Conference on Computer Design and Applications (ICCDA)

作者： Wenna Li Zhaohua Cui Liqun Gao School of Information Science and Engineering Northeastern University Shenyang China School of Information and Control Engineering Liaoning Shihua University Fushun China

ISBN: (纸本)9781424471645;9781424471638

Along with the rapid development of information processing, people attach more and more importance to image compression. Most coding techniques for color image compression employ a de-correlation approach, the RGB space is transformed into a de-correlation color space, then the de-correlated color components are encode separately by the same method for examples JPEG and JPEG2000. A different image encoding method of correlation and wavelet transform approach (CWA) based on human visual system, is presented in this paper. Taking into account the human visual characteristics and instead of de-correlating color components, we employ the existing-color correlation Y, G, R components, after Wavelet transform of these components, G component Wavelet Coefficient is the base component to approximate Y, R components' Wavelet Coefficient on the basis of the least linear squares. Then in order to enhance the algorithm's performance, when the Wavelet Coefficient approximation of Y, R components, different sub-band choice different size block on different sub-band characteristics. G component Wavelet Coefficients after of quantization is encoded using adaptive Huffman coder based on different sub-band, and Huffman bit stream can be encoded using arithmetic coder. The Wavelet Coefficient approximation of Y, R components convert char stream, then is encoded using Huffman coder. Experimental results show that the proposed correlation and wavelet transform image coder based on human visual system offers coding performance superior to presently available algorithms based on the common de-correlation approach.

关键词： Image coding Bit rate Wavelet transforms Wavelet coefficients Humans transform coding Visual system Streaming media Information processing Color

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Scalable-to-lossless transform domain distributed video coding

Scalable-to-lossless transform domain distributed video codi...

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IEEE Workshop on Multimedia Signal Processing

作者： Xin Huang Anna Ukhanova Anton Veselov Søren Forchhammer Marat Gilmutdinov DTU Fotonik Technical University of Denmark Lyngby Denmark Saint Petersburg State University of Aerospace Instrumentation Saint Petersburg Russia

Distributed video coding (DVC) is a novel approach providing new features as low complexity encoding by mainly exploiting the source statistics at the decoder based on the availability of decoder side information. In this paper, scalable-to-lossless DVC is presented based on extending a lossy transform Domain Wyner-Ziv (TDWZ) distributed video codec with feedback. The lossless coding is obtained by using a reversible integer DCT. Experimental results show that the performance of the proposed scalable-to-lossless TDWZ video codec can outperform alternatives based on the JPEG 2000 standard. The TDWZ codec provides frame by frame encoding. Comparing the lossless coding efficiency, the proposed scalable-to-lossless TDWZ video codec can save up to 5%-13% bits compared to JPEG LS and H.264 Intra frame lossless coding and do so as a scalable-to-lossless coding.

关键词： Encoding Video codecs Decoding Discrete cosine transforms Video coding transform coding

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A 4D nth-order Walsh orthogonal transform algorithm used for color image coding

A 4D nth-order Walsh orthogonal transform algorithm used for...

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International Conference on Image Analysis and Signal Processing, IASP

作者： Aijun Sang Tiening Sun Hexin Chen Hua Feng School of Communication Engineering Jilin University Changchun China

Based on the multi-dimensional matrix theory, this paper introduced four-dimensional (4D) model, and deduce the Walsh orthogonal transform in 4D nth-order matrix space. This method is used for color image coding. We obtained very good results. 4D nth-order matrix model can express 4D data in a unified mathematical model for processing. On one hand, it considers the high efficiency of classical matrix transform in the aspect of removing redundancy of color space. On the other hand, it overcomes the restriction of traditional two-dimensional matrix multiplication. Favorable image compression effect can be obtained by 4D Walsh orthogonal transform and traditional discrete cosine transform.

关键词： Color Image coding Discrete transforms Mathematical model Sun Discrete cosine transforms transform coding Quaternions Artificial intelligence Digital communication

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Recursive Implementation of the Distributed Karhunen-Loeve transform

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2010年第10期58卷 5320-5330页

作者： Amar, Alon Leshem, Amir Gastpar, Michael Delft Univ Technol Fac Elect Engn NL-2628 CD Delft Netherlands Bar Ilan Univ Sch Engn IL-52900 Ramat Gan Israel Univ Calif Berkeley Dept Elect Engn & Comp Sci Berkeley CA 94720 USA

In the distributed linear source coding problem, a set of distributed sensors observe subsets of a data vector with noise, and provide the fusion center linearly encoded data. The goal is to determine the encoding matrix of each sensor such that the fusion center can reconstruct the entire data vector with minimum mean square error. The recently proposed local Karhunen-Loeve transform approach performs this task by optimally determining the encoding matrix of each sensor assuming the other matrices are fixed. This approach is implemented iteratively until convergence is reached. Herein, we propose a greedy algorithm. In each step, one of the encoding matrices is updated by appending an additional row. The algorithm selects in a greedy fashion a single sensor that provides the largest improvement in minimizing the mean square error. This algorithm terminates after a finite number of steps, that is, when all the encoding matrices reach their predefined encoded data size. We show that the algorithm can be implemented recursively, and compared to the iterative approach, the algorithm reduces the computational load from cubic dependency to quadratic dependency on the data size. This makes it a prime candidate for on-line and real-time implementations of the distributed Karhunen-Loeve transform. Simulation results suggest that the mean square error performance of the suggested algorithm is equivalent to the iterative approach.

关键词： Distributed compression distributed Karhunen-Loeve transform distributed transforms principal component analysis source coding transform coding

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Variable Block Size transforms with Higher Order Kernels for (Ultra) High Definition Video coding

Variable Block Size Transforms with Higher Order Kernels for...

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Conference on Visual Information Processing and Communication

作者： Lee, Bumshik Ahn, Sangsoo Kim, Munchurl Kim, Hui Yong Kim, Jongho Jeong, Se Yoon Korea Adv Inst Sci & Technol Dept Informat & Commun Engn 119 Munji St Daejeon 305732 South Korea ETRI Daejeon 305750 South Korea

ISBN: (纸本)9780819479365

In this paper, 16-order and 32-order integer transform kernels are designed for the HD video coding in H.264 vertical bar MPEG-4 AVC and the performance analyses for large transforms are presented. An adaptive block size transform coding scheme is also proposed based on the proposed transform kernels. Thus, additional 16-order (16 x 16, 16 x 8 and 8x16) and 32-order (32 x 32, 32 x 16 and 16 x 32) transforms are performed in addition to 8 x 8 and 4 x 4 transforms which are exploited in the Fidelity Range Extension of H.264 vertical bar MPEG-4 AVC. The experimental results show that the variable block size transforms with the proposed higher order transform kernels yields 14.96% of bit saving in maximum for HD video sequences.

关键词： transform coding Integer transform High Definition Video coding H.264 vertical bar MPEG-4 AVC

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A Modified BISK Algorithm for 3D Dual-TreeWavelet transform coding

A Modified BISK Algorithm for 3D Dual-TreeWavelet Transform ...

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Data Compression Conference (DCC)

作者： Joseph B. Boettcher James E. Fowler Department of Electrical and Computer Engineering GeoResources Institute (GRI) Mississippi State University Starkville MS USA

In this paper presents a video-coding system that does not perform explicit ME/MC but instead relies on the DDWT to isolate moving signal features. To counteract the redundancy of the DDWT, a noise-shaping process increases the sparsity of the transform coefficients, resulting in a high degree of spatiotemporally coherent regions of insignificant coefficients. The transform coefficients are coded with binary set-partitioning using k-d trees (BISK) in an algorithm (DDWT-BISK) that exploits both the within-subband spatiotemporal coherency as well as cross-subband correlation to achieve efficient coding. Whereas a prior DDWT-based coder (DDWTVC2) exploits correlation as it exists across subbands in the DDWT, our DDWT-BISK coder additionally exploits coherent regions of insignificant coefficients that occur within subbands, a coherence that must necessarily be substantial due to the sparsity imposed by the noise-shaping process.

关键词： transform coding Discrete wavelet transforms Motion estimation Feedback loop Noise shaping Spatiotemporal phenomena Filtering algorithms Motion compensation Discrete transforms Computational complexity

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Luby transform coding Aided Bit-Interleaved Coded Modulation for the Wireless Internet

Luby Transform Coding Aided Bit-Interleaved Coded Modulation...

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IEEE Conference on Vehicular Technology (VTC)

作者： R. Y. S. Tee T. D. Nguyen S. X. Ng L.-L. Yang L. Hanzo School of ECS University of Southampton UK

Bit-Interleaved Coded Modulation using Iterative Decoding (BICM-ID) is amalgamated with Luby transform (LT) coding. The resultant joint design of the physical and data link layer substantially improves the attainable Bit Error Rate (BER) performance. A Cyclic Redundancy Check (CRC) combined with a novel Log-Likelihood Ratio (LLR) based packet reliability estimation method is proposed for the sake of detecting and disposing of erroneous packets. Subsequently, bit-by-bit LT decoding is proposed, which facilitates a further BER improvement at a lower number of BICM-ID iterations. Finally, we revisit the pseudo random generator function used for designing the LT generator matrix.

关键词： transform coding Interleaved codes Modulation coding Internet Cyclic redundancy check Iterative decoding Bit error rate Automatic repeat request Feedback Signal to noise ratio

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Multiple Description transform coding: A New Design Approach

Multiple Description Transform Coding: A New Design Approach

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IEEE International Conference on Multimedia and Expo (ICME)

作者： Bing Zeng Shuyuan Zhu Department of Electronic and Computer Engineering Hong Kong University of Science and Technology Kowloon Hong Kong China

Multiple-description coding (MDC) is an effective technique to support error-prone transmission in the scenario of multiple channels. Typically, an MDC is designed in the DCT domain where a pair-wise correlating transform (PCT) or some generalized version is further applied to some DCT coefficients of each image block. Although these correlating transforms offer a freedom of compromising the overall coding quality and the redundancy, none of them can be made optimal after taking into consideration the quantization characteristics. In this paper, we present a new design approach in which we will do a novel grouping of all DCT coefficients (not necessarily pair-wise) such that the distortion measured on some specified pixels within each image block is minimized. An interesting property of this new MDC design is that, when all descriptions are received, it provides a coding quality that becomes higher than the target quality set in the corresponding single-description coding (SDC) design.

关键词： transform coding Discrete cosine transforms Redundancy Quantization Image reconstruction Design engineering Computer errors Distortion measurement Pixel Image quality

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Luby transform coding Aided Iterative Detection for Downlink SDMA Systems

Luby Transform Coding Aided Iterative Detection for Downlink...

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IEEE Workshop on Signal Processing Systems (SIPS)

作者： C. Y. Wei T. D. Nguyen N. Wu J. Akhtman L.L. Yang L. Hanzo School of ECS University of Southampton UK

A Luby transform (LT) coded downlink Spatial Division Multiple Access (SDMA) system using iterative detection is proposed, which invokes a low-complexity near-Maximum-Likelihood (ML) Sphere Decoder (SD). The Ethernet-based Internet section of the transmission chain inflicts random packet erasures, which is modelled by the Binary Erasure Channel (BE), while the wireless downlink imposes both fading and noise. A novel Log-Likelihood Ratio based packet reliability meric is used for identifying the channel-decoded packets, which are likely to be error-infested. Packets having residual errors must not be passed on to the LT decoder for the sake of avoiding LT-decoding-induced error propagation. The proposed scheme is capable of maintaining an infinitesimally low packet error ratio in the downlink of the wireless Internet for E b /N 0 values in excess of about 3dB.

关键词： transform coding Downlink Multiaccess communication Decoding Internet Transmitters Convolutional codes MIMO Throughput Convolution

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A High-Quality Speech and Audio Codec With Less Than 10-ms Delay

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IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING 2010年第1期18卷 58-67页

作者： Valin, Jean-Marc Terriberry, Timothy B. Montgomery, Christopher Maxwell, Gregory Octasic Inc Montreal PQ H1Y 3L1 Canada Xiph Org Fdn Somerville MA 02144 USA RedHat Inc Westford MA 01886 USA Juniper Networks Inc Herndon VA 20171 USA

With increasing quality requirements for multimedia communications, audio codecs must maintain both high quality and low delay. Typically, audio codecs offer either low delay or high quality, but rarely both. We propose a codec that simultaneously addresses both these requirements, with a delay of only 8.7 ms at 44.1 kHz. It uses gain-shape algebraic vector quantization in the frequency domain with time-domain pitch prediction. We demonstrate that the proposed codec operating at 48 kb/s and 64 kb/s out-performs both G. 722.1C and MP3 and has quality comparable to AAC-LD, despite having less than one fourth of the algorithmic delay of these codecs.

关键词： Audio coding low-delay speech coding super-wideband transform coding

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