检索结果-内蒙古大学图书馆

Forgery localization in images based on joint statistics of image blocks with neighbouring blocks

IET image PROCESSING 2021年第9期15卷 1893-1908页

作者： Singhal, Divya Gupta, Abhinav Jaypee Inst Informat Technol Dept Elect & Commun Engn A-10Sect 62 Noida 201301 Uttar Pradesh India

Flawless image forensic analysis necessitates precise identification of tampering regions in digital images along with the determination of state of an image (original or forged). Most of the efforts towards localization of forgeries involve localization of information-changing forgeries with less focus towards localization of information-preserving forgeries. This paper proposes a new information-preserving forgery localization method to localize 10 different tampering types exploiting the fact that joint statistics of locally forged regions and neighbouring original regions is disturbed. The proposed 18-dimensional detector is trained using ensemble classifier for fine-grain identification of forged regions in post-JPEG compressed images and results are compared with two recent state-of-the-art detectors. The results demonstrate the effectiveness of the proposed detector with significant performance gain over existing detectors, particularly for localization in images that are compressed with low quality factors of compression.

关键词： Optical, image and video signal processing image and video coding Computer vision and image processing techniques

来源：评论

学校读者我要写书评

暂无评论

Kolmogorov superposition theorem for image compression

引用

IET image PROCESSING 2012年第8期6卷 1114-1123页

作者： Leni, P. -E. Fougerolle, Y. D. Truchetet, F. Univ Burgundy IUT Le Creusot CNRS UMR 6306 LE2I Lab F-71200 Le Creusot France

The authors present a novel approach for image compression based on an unconventional representation of images. The proposed approach is different from most of the existing techniques in the literature because the compression is not directly performed on the image pixels, but is rather applied to an equivalent monovariate representation of the wavelet-transformed image. More precisely, the authors have considered an adaptation of Kolmogorov superposition theorem proposed by Igelnik and known as the Kolmogorov spline network (KSN), in which the image is approximated by sums and compositions of specific monovariate functions. Using this representation, the authors trade the local connectivity and the traditional line-per-line scanning, in exchange of a more adaptable and univariate representation of images, which allows to tackle the compression tasks in a fundamentally different representation. The contributions lie in the several strategies presented to adapt the KSN algorithm, including the monovariate construction, various simplification strategies, the proposal of a more suitable representation of the original image using wavelets and the integration of this scheme as an additional layer in the JPEG 2000 compression engine, illustrated for numerous images at different bit rates.

关键词： image representation splines (mathematics) data compression KSN algorithm JPEG 2000 compression Computer vision and image processing techniques monovariate construction image and video coding image pixel image coding wavelet-transformed image monovariate representation wavelet transforms Interpolation and function approximation (numerical analysis) compression task image compression Kolmogorov spline network Kolmogorov superposition theorem line-per-line scanning Integral transforms in numerical analysis Igelnik monovariate function

来源：评论

学校读者我要写书评

暂无评论

Design of a context-adaptive variable length encoder for real-time video compression on reconfigurable platforms

引用

IET image PROCESSING 2012年第4期6卷 301-308页

作者： Licciardo, G. D. Albanese, L. Freda Univ Salerno Dept Elect & Informat Engn DIEII I-84084 Salerno Italy

In this study, a new context-adaptive variable length-coding encoder architecture is proposed particularly aimed to be implemented with field programmable logics (FPL) like FPGAs. The design implements different approaches in order to minimise the area cost as well as to speed up the coding efficiency, which allows real-time compression of 1080 p video streams coded in YCbCr 4:2:0 format. Priority cascading logics have been implemented in order to increase the parallelisation degree of the pre-coding stage, thus favouring the limitation of the number of clock cycles needed for the extraction of symbols from the input data, whereas the employment of the arithmetic table elimination technique has allowed a large-area reduction of the encoder thanks to the elimination of 18 of the 38 tables needed for the encoding stage. The design achieves real time elaboration with an operation frequency of 63 MHz and occupies 2200 look-up table (LUT)s when implemented on a low-cost, low-end XILINX Spartan 3 FPGA, thus overcoming the most recent FPL implementation and making this encoder quite comparable both in terms of area and speed with some recently proposed ASIC implementations, so that it turns out to be a valid alternative also for application specific implementations.

关键词： precoding parallelisation degree field programmable logics look-up table reconfigurable platform data compression table lookup variable length codes field programmable gate arrays FPL implementation Xilinx Spartan 3 real-time video compression coding efficiency priority cascading logics image and video coding precoding stage arithmetic table elimination technique low-end XILINX Spartan 3 FPGA Logic circuits Computer architecture video coding Logic and switching circuits clocks reconfigurable architectures YCbCr 4:2:0 format context-adaptive variable length-coding encoder architecture video signal processing video streaming length-coding encoder architecture symbols extraction clock cycle ASIC implementation

来源：评论

学校读者我要写书评

暂无评论

Texture segmentation in the joint photographic expert group 2000 domain

引用

IET image PROCESSING 2011年第6期5卷 554-559页

作者： Hsin, H. -C. Natl United Univ Dept Comp Sci & Informat Engn Taipei Taiwan

image segmentation is an important task in many image processing systems. For efficient transmission over a band-limited channel, original images are often compressed before being stored in databases. In order to avoid the burden of decompressing an image, it is desirable to extract features directly from a code stream. This approach saves computational time significantly. The look up table used for the MQ coder defined in joint photographic expert group 2000 (JPEG2000) called the MQ table provides probability models for bit-plane coding of wavelet coefficients, the wavelet histogram information can be obtained directly from a JPEG2000 code stream. Thus, the MQ feature based on the MQ table is proposed to segment an image in the JPEG2000 domain directly. Experimental results of clustering these features by using the simple K-means algorithm show the potential of MQ feature.

关键词： texture segmentation band-limited channel data compression image processing systems code stream Computer vision and image processing techniques image and video coding image coding MQ feature image segmentation pattern clustering wavelet coefficients feature extraction joint photographic expert group 2000 domain image compression image texture Computational complexity computational complexity /(-means algorithm computational time JPEG2000 code stream bit-plane coding wavelet histogram information

来源：评论

学校读者我要写书评

暂无评论

Colour image watermarking for tamper proofing and pattern-based recovery

引用

IET image PROCESSING 2012年第5期6卷 445-454页

作者： Liu, K. -C. Information Educating Center Taiwan Hospitality and Tourism College Taiwan

The rapid development of the internet allows digital media being easily delivered, copied and even tampered. The watermarking issue has thus focused mainly on the medium of authentication. In this study, an efficient self-embedding watermarking scheme for colour image authentication is proposed. The scheme is designed to achieve tamper proofing and high-quality recovery. The scheme is efficient because the validity of image blocks is simply proofed by using a dual-option parity-check method and morphological operations. The former is used to generate authentication information for obtaining better results of tamper proofing and the latter is used to further improve the neighbouring connectivity of the proofing results. To achieve high-quality recovery of the tampered image, the feature information of the host colour image and its corresponding block-edge-pattern information are properly organised to embed into three colour components of the host colour image. Meanwhile, the embedding information is appropriately distributed over luminance and chrominance components of the colour image in the YCbCr colour space such that the quality of the watermarked image can be better obtained. The simulation results show that the proposed watermarking scheme can effectively proof the tempered region with high detection rate and can restore the tempered region with high quality.

关键词： image colour analysis Internet Computer vision and image processing techniques tamper proofing image watermarking image and video coding image block validity image coding colour image authentication information high-quality pattern-based recovery high-quality recovery self-embedding watermarking scheme feature information dual-option parity-check method morphological operation digital media image sensors colour image watermarking Data security chrominance component luminance component block-edge-pattern information

来源：评论

学校读者我要写书评

暂无评论

Optimal model-based complexity control for H.264 video encoding

引用

IET image PROCESSING 2012年第1期6卷 60-71页

作者： Chien, M. -C. Chang, P. -C. Natl Cent Univ Dept Commun Engn Tao Yuan 320 Taiwan

An H.264 video encoder adopts multiple encoding tools to achieve high coding efficiency at the expense of high computational complexity. The allowable computational complexity for real-time video encoding, however, is generally limited in a wireless handset. This research proposes a complexity control mechanism that is composed of two algorithms to minimise the distortion of each encoded video frame under the computational complexity constraint and the rate constraint. The first proposed algorithm performs optimal complexity allocation among encoding tools based on a new complexity-rate-distortion (C-R-D) model. This model precisely describes how each encoding tool influences the C-R-D performance of the encoder with concise formulas. Accordingly, the algorithm obtains the optimal complexity of each encoding tool by a closed-form solution with small complexity overhead. Based on a new C-D model of motion estimation, this work proposes the second algorithm that performs optimal complexity allocation among macro-blocks to further allocate suitable complexity to each macro-block. Experiments performed on a software-optimised source code show that these two algorithms yield superior performance to the existing algorithms.

关键词： closed-form solution high computational complexity constraint H.264 video encoder wireless handset image and video coding motion estimation radiocommunication complexity-rate-distortion model H.264 video encoding optimal complexity allocation video coding real-time video encoding optimal model-based complexity control mechanism video signal processing Radio links and equipment high coding efficiency software-optimised source code communication complexity multiple encoding tools

来源：评论

学校读者我要写书评

暂无评论

Visual secret sharing for general access structures by random grids

引用

IET INFORMATION SECURITY 2012年第4期6卷 299-309页

作者： Wu, X. Sun, W. Sun Yat Sen Univ Sch Informat Sci & Technol Guangzhou 510006 Guangdong Peoples R China Sun Yat Sen Univ Sch Software Guangzhou 510006 Guangdong Peoples R China

Visual secret sharing (VSS) is a way to protect a secret image among a group of participants by using the notions of perfect ciphers and secret sharing. However, each share generated by conventional VSS is m times as big as the original secret image, where m is called pixel expansion. Random grid (RG) is an alternative approach to implement VSS without pixel expansion. However, reported RG-based VSS methods are threshold schemes. In this study, RG-based VSS for general access structures is presented. Secret image is encoded into n RGs while qualified sets can recover the secret visually and forbidden sets cannot. The proposed scheme is a generalisation of the threshold methods, where those reported RG-based schemes can be considered as the special cases of the proposed scheme. Experimental results are provided, demonstrating the effectiveness and advantages of the proposed scheme.

关键词： general access structure visual secret sharing cryptography Computer vision and image processing techniques image and video coding image coding secret image Data security Cryptography pixel expansion RG-based VSS method threshold method random grid approach perfect cipher

来源：评论

学校读者我要写书评

暂无评论

Acceleration of fractal image compression using fuzzy clustering and discrete-cosine-transform-based metric

引用

IET image PROCESSING 2012年第7期6卷 1024-1030页

作者： Jaferzadeh, K. Kiani, K. Mozaffari, S. Semnan Univ Elect & Comp Dept Semnan Iran

The encoding step in a fractal image compression is very time consuming, because a large numbers of sequential search through a list of domains are needed to find the best match for a given range block. Adaptive domain clustering is one solution to overcome this computational burden. The use of a new metric with fewer operations for domain-range blocks comparison is fruitful. In this study, range and domain blocks are categorised by fuzzy c-mean-clustering approach and compared with the use of new metric based on discrete cosine transform coefficient. Experimental results show that by clustering image pixels into five clusters, the encoding step was 8.88 times faster than the full-search method (no clustering) at the expense of some reduction in the decoded image's quality. But the proposed method with the same number of clusters speeds up the encoding process by 45 with lower PSNR decay.

关键词： adaptive domain clustering discrete cosine transforms domain-range blocks comparison fractal image compression acceleration sequential search image quality decoding encoding process Computer vision and image processing techniques image and video coding image coding fuzzy set theory Integral transforms pattern clustering discrete-cosine-transform-based metric fuzzy clustering decoding image pixels clustering encoding step Combinatorial mathematics fuzzy c-mean-clustering approach domain blocks fractals

来源：评论

学校读者我要写书评

暂无评论

Efficient compression algorithm for hyperspectral images based on correlation coefficients adaptive 3D zerotree coding

引用

IET image PROCESSING 2008年第2期2卷 72-82页

作者： Liu, G. Zhao, F. Xi An Jiao Tong Univ Sch Elect & Informat Engn Xian 710049 Peoples R China

The authors propose an efficient compression algorithm for hyperspectral images, which is based on the correlation coefficients adaptive asymmetric tree three-dimensional (3D) set partitioning in hierarchical trees (AT-3DSPIHT) coding of the asymmetric 3D wavelet transform (A3D-DWT) coefficients. According to the characteristics of the correlation coefficients between adjacent spectral bands, a binary tree spectral band grouping algorithm is carried out to divide the adjacent spectral bands into different mode groups. Along with this, an appropriate A3D-DWT with the corresponding decomposition levels and a proper AT-3D zerotree are determined adaptively. Several airborne visible/infrared imaging spectrometer images are used to evaluate the proposed algorithm. Compared with the state-of-the-art 3D-DWT based algorithms, the proposed adaptive AT-3DSPIHT achieves the best compression performance at lower bit rates. Moreover, at the low correlated adjacent bands, the proposed algorithm also outperforms the 2DSPIHT algorithm.

关键词： adaptive 3D zerotree coding discrete wavelet transform geophysical signal processing Function theory, analysis data compression spectral analysis Geophysics computing Computer vision and image processing techniques image and video coding correlation coefficient image coding Integral transforms adaptive codes discrete wavelet transforms binary tree spectral band grouping algorithm hyperspectral image compression Algebra, set theory, and graph theory Geophysical techniques and equipment trees (mathematics) set theory correlation methods Instrumentation and techniques for geophysical, hydrospheric and lower atmosphere research asymmetric tree three-dimensional set partitioning Combinatorial mathematics hierarchical trees

来源：评论

学校读者我要写书评

暂无评论

Performance of an efficient heuristic scheduling algorithm for MPEG-4 traffic in high data rate wireless personal area network

引用

IET COMMUNICATIONS 2011年第8期5卷 1090-1095页

作者： Yang, G. Hu, H. Rong, L. Du, Y. Zhejiang Univ Dept Informat Sci & Elect Engn Hangzhou 310058 Zhejiang Peoples R China Shanghai Res Ctr Wireless Commun Shanghai 200050 Peoples R China Huawei Technol Co Ltd Shanghai 200050 Peoples R China

In this research, the authors study the impact of a controlling parameter on system performances of our previously proposed heuristic channel-aware scheduling algorithm. In addition, parameter optimisation for a combined performance measure is also discussed. The investigation is carried out through numerical simulations via ns-2. When compared with other algorithms, the proposed algorithm uniformly shows the best performance, with the performance gain being more evident for bad channel. The findings are useful for system designers.

关键词： image and video coding heuristic channel-aware scheduling algorithm video coding video signal processing Radio links and equipment Other computer networks MPEG-4 traffic wireless personal area network video communication Computer communications personal area networks ns-2 simulations scheduling

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：