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IEEE TRANSACTIONS ON IMAGE PROCESSING 2012年第6期21卷 3108-3114页

作者： Zhang, Xinpeng Feng, Guorui Ren, Yanli Qian, Zhenxing Shanghai Univ Sch Commun & Informat Engn Shanghai 200072 Peoples R China

This paper proposes a novel scheme of scalable coding for encrypted images. In the encryption phase, the original pixel values are masked by a modulo-256 addition with pseudorandom numbers that are derived from a secret key. After decomposing the encrypted data into a downsampled subimage and several data sets with a multiple-resolution construction, an encoder quantizes the subimage and the Hadamard coefficients of each data set to reduce the data amount. Then, the data of quantized subimage and coefficients are regarded as a set of bitstreams. At the receiver side, while a subimage is decrypted to provide the rough information of the original content, the quantized coefficients can be used to reconstruct the detailed content with an iteratively updating procedure. Because of the hierarchical coding mechanism, the principal original content with higher resolution can be reconstructed when more bitstreams are received.

关键词： Hadamard transform image compression image encryption scalable coding

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scalable coding of very high resolution video using the virtual zerotree

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 1997年第5期7卷 719-727页

作者： Wang, Q Ghanbari, M UNIV ESSEX DEPT ELECT SYST ENGN COLCHESTER CO4 3SQ ESSEX ENGLAND

coding of HDTV and super high definition video requires not only high performance compression but also compatibility and scalability to satisfy transmission channels of various speeds and capacity and receivers working at different resolutions, A compatible and scalable coding scheme has been developed for these video signals, Wavelet decomposition is performed such that the low frequency band is of common intermediate format (CIF) order, which forms a low-resolution core of the full-sized video and is coded by MPEG. The high-frequency wavelet coefficients are coded by the proposed virtual zerotree which encodes the wavelet coefficients more efficiently than the simple zerotree, Also embedded in the scheme is the hierarchical motion compensation that gives high performance with a large capable compensation range, requires minimum computation, and reduces overhead motion information.

关键词： high quality video motion estimation scalable coding video compression wavelet transform

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scalable coding of 3D holoscopic image by using a sparse interlaced view image set and disparity map

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MULTIMEDIA TOOLS AND APPLICATIONS 2018年第1期77卷 1261-1283页

作者： Liu, Deyang An, Ping Ma, Ran Yang, Chao Shen, Liquan Li, Kai Shanghai Univ Sch Commun & Informat Engn Shanghai 200072 Peoples R China Anqing Normal Univ Sch Comp & Informat Anqing 246133 Peoples R China

3D holoscopic imaging, also known as integral imaging, light field imaging or plenoptic imaging, can provide natural and fatigue-free 3D visualization. Holoscopic contents captured by the plenoptic camera contain both spatial and angular information of a 3D scene. Therefore, view images with different perspectives can be rendered from the holoscopic contents. A coding scheme to compress the 3D holoscopic image by exploiting the high spatial correlation among the rendered view images will be advantageous. Therefore, in this paper, an efficient scalable coding scheme is proposed to compress the 3D holoscopic image by utilizing such high spatial correlation. We firstly re-arrange the holoscopic contents to form an interlaced view image. A sparse format is then proposed to express the interlaced view image. With the reconstructed image derived by disparity map based sifting and interpolation, the full interlaced view image is coded by using the reconstructed image as a reference frame. As an outcome of the representation, a scalable structure with three layers can be provided by the proposed scheme. Experimental results demonstrate that the 3D holoscopic image can be compressed efficiently with over 44 percent bit rate reduction compared with HEVC. Meanwhile, the proposed scheme can also surpass several other prediction schemes in this field.

关键词： 3D holoscopic image Image coding scalable coding HEVC

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scalable coding based on adaptive subband for interlaced video sequences

Scalable coding based on adaptive subband for interlaced vid...

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International Conference on Image Processing

作者： Sawada, K Yoshida, T Aichi Inst of Technology Aichi-ken Japan

ISBN: (纸本)0818681837

Resolution scalability refers to a picture coding property where pictures at lower different resolutions can be reconstructed by decoding only the subsets of a single coded bit-stream, while the full resolution picture is reconstructed by decoding the total bit-stream. This paper presents a resolution scalable video coding scheme for interlaced video sequences. The proposed scalable coding scheme employs adaptive in-field/in-frame subband for spatial scalability, where in-field subband and in-frame subband are adaptively used for moving portions and stationary portions, respectively. It also employs adaptive field/frame subsampling for temporal scalability. Experimental results have demonstrated that the proposed adaptive subband gives better picture quality especially for reconstructed lower resolution pictures compared to non adaptive subband.

关键词： Interlaced Video scalable coding subband Self tuning Scalability

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MPEG-2 spatial scalable coding and transport stream error concealment for satellite TV broadcasting using Ka-band

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IEEE TRANSACTIONS ON BROADCASTING 1998年第2期44卷 233-242页

作者： Hsu, YF Chen, YC Huang, CJ Sun, MJ Natl Tsing Hua Univ Dept Elect Engn Hsinchu Taiwan

In this paper, an effective MPEG-2 spatial scalable video codec is designed, and error concealment technique of associated transport stream is proposed. The spatial scalability can provide robust error resilience for Ka-band rain attenuation, as well as the co-existence of HDTV and SDTV systems. In MPEG-2, the spatial scalable encoder combines both spatial and temporal predictions. This paper proposes a near optimal spatial-temporal weighting analyzer to properly assign cv eights Simulation shows that the proposed spatial scalable codec structure outperforms the performance of the other MPEG-2 codecs for TV broadcasting in Ka band using satellites. We also propose a suitable error protection and concealment method for MPEG-2 transport stream. With the combination of scalable coding and error protection systems, the proposed system will achieve high link availability.

关键词： digital television direct broadcasting by satellite error correction microwave propagation television broadcasting television interference television standards tropospheric electromagnetic wave propagation video codecs 18 to 30 GHz HDTV Ka-band MPEG-2 sp microwave propagation television broadcasting codecs tropospheric electromagnetic wave propagation error protection television interference Television Digital television video codecs transport stream Extremely high frequencies error correction scalable coding television standards

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JPEG 2000 Extensions for scalable coding of Discontinuous Media

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2023年 32卷 3092-3107页

作者： Mathew, Reji Naman, Aous Thabit Li, Yue Taubman, David Univ New South Wales Sch Elect Engn & Telecommun Sydney NSW 2052 Australia

In this paper we propose novel extensions to JPEG 2000 for the coding of discontinuous media which includes piecewise smooth imagery such as depth maps and optical flows. These extensions use breakpoints to model discontinuity boundary geometry and apply a breakpoint dependent Discrete Wavelet Transform (BP-DWT) to the input imagery. The highly scalable and accessible coding features provided by the JPEG 2000 compression framework are preserved by our proposed extensions, with the breakpoint and transform components encoded as independent bit streams that can be progressively decoded. Comparative rate-distortion results are provided along with corresponding visual examples which highlight the advantages of using breakpoint representations with accompanying BD-DWT and embedded bit-plane coding. Recently our proposed extensions have been adopted and are in the process of being published as a new Part 17 to the JPEG 2000 family of coding standards.

关键词： Image coding Transform coding Transforms Discrete wavelet transforms Media Encoding Spatial resolution JPEG 2000 scalable coding DWT EBCOT

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Multi-Objective Optimization and Characterization of Pareto Points for scalable coding

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2019年第7期29卷 2096-2111页

作者： Hwang, Wen-Liang Lee, Chia-Chen Peng, Guan-Ju Acad Sinica Inst Informat Sci Taipei 115 Taiwan Realtek Semicond Corp Hsinchu 300 Taiwan Natl Chung Hsing Univ Dept Appl Math Taichung 402 Taiwan

In this paper, we formulated the optimal bit-allocation problem for a scalable codec for images/videos as a graph-based constrained vector-valued optimization problem with many optimal solutions, which are referred to as Pareto points. Pareto points are generally derived using weighted sum scalarization;however, it has yet to be determined whether all Pareto points can be derived using this approach. This paper addresses this issue. When presented as a theorem, our results indicate that as long as the rate-distortion function of each resolution is strictly decreasing and convex and the Pareto points form a continuous curve, then all Pareto points can be derived using scalarization. The theorem is verified using the state-of-the-art scalable coding method H.264/SVC and a scalability extension of High Efficiency Video coding (HEVC). We highlight a number of easily interpretable Pareto points that represent a good trade-off between candidate resolutions. The proximity point is defined as the Pareto point closest to the ideal performance for each resolution. We also model the Pareto points as a function of total bit rate and demonstrate that the Pareto points at other target bit rates can be predicted.

关键词： scalable coding multi-criterion optimization

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On the Role of the Refinement Layer in Multiple Description coding and scalable coding

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IEEE TRANSACTIONS ON INFORMATION THEORY 2011年第3期57卷 1443-1456页

作者： Wang, Jia Chen, Jun Zhao, Lei Cuff, Paul Permuter, Haim Shanghai Jiao Tong Univ Dept Elect Engn Shanghai 200240 Peoples R China McMaster Univ Dept Elect & Comp Engn Hamilton ON L8S 4K1 Canada Stanford Univ Dept Elect Engn Stanford CA 94305 USA Princeton Univ Dept Elect Engn Princeton NJ 08544 USA Ben Gurion Univ Negev Dept Elect & Comp Engn IL-84105 Beer Sheva Israel

We clarify the relationship among several existing achievable multiple description rate-distortion regions by investigating the role of refinement layer in multiple description coding. Specifically, we show that the refinement layer in the El Gamal-Cover (EGC) scheme and the Venkataramani-Kramer-Goyal (VKG) scheme can be removed;as a consequence, the EGC region is equivalent to the EGC* region (an antecedent version of the EGC region) while the VKG region (when specialized to the 2-description case) is equivalent to the Zhang-Berger (ZB) region. Moreover, we prove that for multiple description coding with individual and hierarchical distortion constraints, the number of layers in the VKG scheme can be significantly reduced when only certain weighted sum rates are concerned. The role of refinement layer in scalable coding (a special case of multiple description coding) is also studied.

关键词： Contra-polymatroid multiple description coding rate-distortion region scalable coding successive refinement

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scalable coding & QoS control for next generation network

Scalable coding & QoS control for next generation network

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3rd IASTED International Conference on Communications and Computer Networks

作者： Zhang, C Tu, GF Yi, WD Chinese Acad Sci Grad Sch Sch Informat Sci & Engn Beijing 100049 Peoples R China

ISBN: (纸本)0889865442

scalable video coding and the quality of serves (QoS) is the next generation networks (NGN) key technique in order to adapt various clients' requirement (e.g. quality, spatial resolution and temporal resolution) and bandwidth variation in heterogeneous network. We propose a reduced dimension scalable video coding using wavelet transformation and QoS control method based on fractal interpolation for the next generation network, and realize different types of bit-stream decoders with different complexity and access bandwidth can coexist. Simulation result shows that the wavelet fractal interpolation algorithm bas better performance than the Bi-linear interpolation and no interpolation. When the channel is congests, the network is the lost high frequency sub-band and transmit low frequency sub-band, and the receiver can recover the lost high frequency by WFI or BLI to satisfy different clients' requirements.

关键词： scalable coding QoS for the NGN reduced dimension segmentation

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SNR and temporal scalable coding of 3-D mesh sequences using singular value decomposition

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JOURNAL OF VISUAL COMMUNICATION AND IMAGE REPRESENTATION 2009年第7期20卷 439-449页

作者： Heu, Jun-Hee Kim, Chang-Su Lee, Sang-Uk Korea Univ Dept Elect & Comp Engn Sch Elect Engn Seoul South Korea Seoul Natl Univ Sch Elect Engn Signal Proc Lab Seoul South Korea Seoul Natl Univ INMC Seoul South Korea

A signal-to-noise ratio (SNR) and temporal scalable coding algorithm for 3-D mesh sequences using singular value decomposition (SVD) is proposed in this work. The proposed algorithm employs SVD to represent a mesh sequence with a small number of basis vectors, and encodes those basis vectors with a bit plane coder. We analytically derive the contribution of each bit plane to the reconstructed mesh quality, and transmit the bit planes in the decreasing order of their amounts of contribution. As the decoder receives more bit planes, it reconstructs higher quality mesh sequences progressively. Moreover, we develop a temporal prediction mode to improve the rate-distortion (R-D) performance further, which also supports temporal scalability. Simulation results demonstrate that the proposed algorithm yields significantly better R-D performance than conventional SVD-based coders. (C) 2009 Elsevier Inc. All rights reserved.

关键词： 3-D mesh coding scalable coding Rate-distortion optimization Singular value decomposition SNR scalability Temporal scalability Bit plane coding Mesh sequence

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