检索结果-内蒙古大学图书馆

still image coding based on vector quantization and fractal approximation

IEEE TRANSACTIONS ON image PROCESSING 1996年第4期5卷 587-597页

作者： Kim, IK Park, RH Department of Electronic Engineering Sogang University Seoul South Korea

In this paper, we propose a coding algorithm for still images using vector quantization (VQ) and fractal approximation, in which low-frequency components of an input image are approximated by VQ, and its residual is coded by fractal mapping, The conventional fractal coding algorithms indirectly used the gray patterns of an original image with contraction mapping, whereas the proposed fractal coding method employs an approximated and then decimated image as a domain pool and uses its gray patterns, Thus, the proposed algorithm utilizes fractal approximation without the constraint of contraction mapping, For approximation of an original image, we employ the discrete cosine transform (DCT) rather than conventional polynomial-based transforms. In addition, for variable block-size segmentation, we use the fractal dimension of a block that represents the roughness of the gray surface of a region, Computer simulations with several test images show that the proposed method shows better performance than the conventional fractal coding methods for encoding still pictures.

关键词： Fractals approximation image coding discrete cosine transforms original image Vector quantization still images contraction mapping still image coding fractal coding

来源：评论

学校读者我要写书评

暂无评论

Architectural Design of a Fast Search Algorithm and Implementation to Intra-Mode Decision Block of still image coding

引用

JOURNAL OF CIRCUITS SYSTEMS AND COMPUTERS 2022年第8期31卷 2250148-2250148页

作者： Cekli, Serap Akman, Ali Istanbul Univ Cerrahpasa Dept Elect Elect Engn Istanbul Turkey Maltepe Univ Comp Engn Dept Istanbul Turkey

As a requirement of many modern image compression standards faced today, a computational complexity is observed due to the best mode selection in the intra-prediction stage. This computational complexity is tried to be reduced by various techniques without affecting the performance criteria of the image. In this study, a fast search algorithm, which simplifies the mode selection process of the intra-prediction algorithm and provides calculation with less number of modes is proposed. The hardware architecture of this proposed algorithm is implemented for realization. There are two main sections of the intra-prediction algorithm in image compression, namely the image prediction process and the mode selection process. In this study, main objective is to reduce the process time of the mode selection and the simplification of the hardware design. Sum of absolute difference (SAD) is a frequently used criterion to simplify hardware design. The algorithm searches for the most suitable mode in a single step, where the decision is based on the SAD criterion preferred for the simplicity. The proposed algorithm and related hardware architecture is tested by using various experiments. The number of the modes calculated is reduced effectively, while the process is kept within the acceptable limits in terms of peak signal to noise ratio (PSNR) and compression rate (CR) performance criteria. Therefore, the number of clock cycles observed is considerably reduced. The designed architecture is synthesized for the field programmable gate arrays (FPGA) board and the obtained results are given. In addition, these results are compared with the HM reference software where the corresponding results are in accordance with the reference software.

关键词： Intra-prediction still image coding SAD mode selection architecture

来源：评论

学校读者我要写书评

暂无评论

A new side-match finite-state vector quantization using neural networks for image coding

引用

JOURNAL OF VISUAL COMMUNICATION AND image REPRESENTATION 2002年第3期13卷 335-347页

作者： Huang, YL Chang, RF Natl Chung Cheng Univ Dept Comp Sci & Informat Engn Chiayi 62107 Taiwan

The side-match finite-state vector quantization (SMVQ) schemes improve performance over the vector quantization by exploiting the neighboring vector correlations within the image. In this paper, we propose a neural network side-match finite-state vector quantization (NN-SMVQ) scheme that combines the techniques of neural network prediction and the SMVQ coding method. In our coding scheme, the multilayer perceptron network is used to improve the accuracy of side-match prediction by utilizing the property of the neural network nonlinear prediction. The NN-SMVQ scheme not only has the advantages of the SMVQ scheme but also improves the coded image quality. Experimental results are given and comparisons are made using our NN-SMVQ coding scheme and some other coding techniques. In the experiments, our NN-SMVQ coding scheme achieves the better visual quality about edge region and the best PSNR performance at nearly the same bit rate. This new NN-SMVQ scheme is also simple and efficient for the hardware design. Moreover, the new scheme does not adversely affect other useful functions provided by the conventional SMVQ scheme. (C) 2002 Elsevier Science (USA).

关键词： vector quantization SMVQ multilayer feedforward neural network multilayer perceptron MLP still image coding

来源：评论

学校读者我要写书评

暂无评论

A successive approximation vector quantizer for wavelet transform image coding

引用

IEEE TRANSACTIONS ON image PROCESSING 1996年第2期5卷 299-310页

作者： daSilva, EAB Sampson, DG Ghanbari, M UNIV ESSEX DEPT ELECTR SYST ENGN WIVENHOE PK ENGLAND

A coding method for wavelet coefficients of images using vector quantization, called successive approximation vector quantization (SA-W-VQ) is proposed, In this method, each vector is coded by a series of vectors of decreasing magnitudes until a certain distortion level is reached, The successive approximation using vectors is analyzed, and conditions for convergence are derived, It is shown that lattice codebooks are an efficient tool for meeting these conditions without the need for very large codebooks. Regular lattices offer the extra advantage of fast encoding algorithms, In SA-W-VQ, distortion equalization of the wavelet coefficients can be achieved together with high compression ratio and precise bit-rate control, The performance of SA-W-VQ for still image coding is compared against some of the most successful image coding systems reported in the literature. The comparison shows that SA-W-VQ performs remarkably well at several bit rates and in various test images.

关键词： image coding approximation Wavelet coefficients Cloning Vectors wavelet transforms Vector quantization quantizer fast encoding still image coding compression ratio

来源：评论

学校读者我要写书评

暂无评论

2-dimensional optimum band partition based on band blocks for subband image coding

2-dimensional optimum band partition based on band blocks fo...

引用

Meeting on Visual Communications and image Processing

作者： Kameda, M Ohtake, K Miyahara, M Japan Adv Inst Sci & Technol Tatsunokuchi Ishikawa 9231292 Japan

ISBN: (纸本)0819431249

Subband coding is important (1) to decompose an input signal into an adequate set of subbands considering the property of an input signal and (2) to assign an adequate bits in proportion with the power of each subband signal. Investigation of autocorrelation characteristics of several kinds of images reveals us an isotropic correlation model. Based on this theoretical image model, we have derived the optimum band partition that minimizes the quantization noise power of the reconstructed signal at the receiving end. In order to apply the above theoretical optimum band partition to the image coding, we propose the optimum band partition scheme based on an idea of a set of band blocks, and we present the calculation algorithm with the low computational complexity to determine the optimum band partition. Also, we propose two methods to exploit the non-stationary nature of images, and the filter bank configuration to realize the optimum band partition including these methods. The proposed optimum band partition shows better result than that of the blocking DCT in obtaining the higher compression rate and the higher image quality.

关键词： still image coding subband decomposition optimum band partition quantization noise power improvement band block non-stationary nature of image adaptive band partition

来源：评论

学校读者我要写书评

暂无评论

Fractal image compression with region-based functionality

引用

IEEE TRANSACTIONS ON image PROCESSING 2002年第4期11卷 351-362页

作者： Belloulata, K Konrad, J Univ Sherbrooke Dept Genie Elect & Genie Informat Sherbrooke PQ J1K 2R1 Canada Boston Univ Dept Elect & Comp Engn Boston MA 02215 USA

Region-based functionality offered by the MPEG-4 video compression standard is also appealing for still images, for example to permit object-based queries of a still-image database. A popular method for still-image compression is fractal coding. However, traditional fractal image coding uses rectangular range and domain blocks. Although new schemes have been proposed that merge small blocks into irregular shapes, the merging process does not, in general, produce semantically-meaningful regions. We propose a new approach to fractal image coding that permits region-based functionalities;images are coded region by region according to a previously-computed segmentation map. We use rectangular range and domain blocks, but divide boundary blocks into segments belonging to different regions. Since this prevents the use of standard dissimilarity measure, we propose a new measure adapted to segment shape. We propose two approaches: one in the spatial and one in the transform domain. While providing additional functionality, the proposed methods perform similarly to other tested methods in terms of PSNR but often result in images that are subjectively better. Due to the limited domain-block code-book size, the new methods are faster than other fractal coding methods tested. The results are very encouraging and show the potential of this approach for various internet and still-image database applications.

关键词： fractal image coding region-based coding region-based functionalities still image coding

来源：评论

学校读者我要写书评

暂无评论

Objective Performance Evaluation of the HEVC Main still Picture Profile

引用

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2015年第5期25卷 790-797页

作者： Tung Nguyen Marpe, Detlev Heinrich Hertz Inst Nachrichtentech Berlin GmbH Fraunhofer Inst Telecommun Dept Image Proc & Analyt Image & Video Coding Grp D-10587 Berlin Germany

The first version of the High Efficiency Video coding (HEVC) standard was approved by both ITU-T and ISO/IEC in 2013 and includes three profiles: Main and Main 10 for typical video data with 8 and 10 bits, respectively, as well as a profile referred to as Main still Picture (MSP) profile. Apparently, the MSP profile extends the HEVC application space toward still images which, in turn, brings up the question of how this HEVC profile performs relative to existing still image coding technologies. This paper aims at addressing this question from a coding-efficiency point-of-view by presenting a rate-distortion performance analysis of the HEVC MSP profile in comparison to other popular still image and video compression schemes, including JPEG, JPEG 2000, JPEG XR, H.264/MPEG-4 AVC, VP8, VP9, and WebP. In summary, it can be stated that the HEVC MSP profile provides average bit-rate savings in the range from 10% to 44% relative to the whole set of competing video and still image compression schemes when averaged over a representative test set of photographic still images. Compared with Baseline JPEG alone, the average bit-rate saving for the HEVC MSP profile is 44%.

关键词： High Efficiency Video coding (HEVC) Main still Picture (MSP) profile standards still image coding video compression

来源：评论

学校读者我要写书评

暂无评论

Satellite image compression by post-transforms in the wavelet domain

引用

SIGNAL PROCESSING 2010年第2期90卷 599-610页

作者： Delaunay, X. Chabert, M. Charvillat, V. Morin, G. CNES TeSA NOVELTIS F-31520 Ramonville St Agne France IRIT ENSEEIHT F-31071 Toulouse 7 France

This paper proposes a novel compression scheme with a tunable complexity-rate-distortion trade-off. As images increase in size and resolution. more efficient compression schemes with low complexity are required on-board Earth observation satellites. The standard of the Consultative Committee for Space Data Systems (CCSDS) defines a strip-based compression scheme with the advantages of a low complexity and an easy rate control [CCSDS, image Data Compression Recommended Standard CCSDS 122.0-B-1 Blue Book, November 2005]. However, future mission specifications expect higher performance in terms of rate-distortion. The scheme proposed in this paper intends to perform better than the CCSDS standard while preserving low complexity and easy rate control. Moreover, to comply with existing on-board devices, the proposed core compression engine still uses the wavelet transform but in association with a linear post-processing inspired from the bandelet transform. The post-transform decomposes a small block of wavelet coefficients on a particular basis. This basis is adaptively selected within a predefined dictionary by rate-distortion optimization. The computational complexity depends upon the dictionary size and of the basis structure. An extremely simple dictionary, reduced to the Hadamard basis, is proposed. The post-transform efficiency is illustrated by experiments on various Earth observation images provided by the French Space Agency (CNES). (C) 2009 Elsevier B.V. All rights reserved.

关键词： still image coding Discrete transforms Wavelet transform Satellite application

来源：评论

学校读者我要写书评

暂无评论

SOURCE-coding OF SPEECH AND VIDEO SIGNALS

引用

PROCEEDINGS OF THE IEEE 1990年第7期78卷 1233-1249页

作者： SINGHAL, S LEGALL, D CHEN, CT Bell Commun. Res. Morristown NJ

Some digital source coding techniques for speech and video are reviewed. Predictive coding of speech, multipulse and code-excited coders and frequency-domain coders are discussed and compared for the coding of speech signals, and intraframe and still image coding and interframe coding are examined for the coding of image and video signals. The emphasis is on those algorithms that offer high compression while maintaining the perceptual quality of the source signals are discussed. Some algorithms that are general waveform coding algorithms and do not strictly depend on the input source are included

关键词： code-excited coders decoding digital source coding techniques encoding frequency-domain coders general waveform coding algorithms high compression interframe coding intraframe image coding multipulse coders picture processing productive coding reviews speech analysis and processing speech signals still image coding video signals video signals

来源：评论

学校读者我要写书评

暂无评论

DIFFERENTIAL-SPIHT FOR image SEQUENCE coding

DIFFERENTIAL-SPIHT FOR IMAGE SEQUENCE CODING

引用

IEEE International Conference on Acoustics, Speech, and Signal Processing

作者： Yang Hu William A. Pearlman Department of Electrical Computer and Systems Engineering Rensselaer Polytechnic Institute Troy NY 12180

ISBN: (纸本)9781424442959

Efficient image sequence coding exploits both spatial correlation and temporal correlation. SPIHT is a powerful algorithm in exploiting spatial correlations for still image coding. Based on SPIHT, we present a novel approach to exploit temporal correlations for image sequence coding, while maintaining single frame, random access decoding. The socalled Differential-SPIHT takes advantage of inter-frame correlations by reusing the significance testing data of a SPIHT coded frame. From simulation results of videos and volumetric medical images, Differential-SPIHT offers significant reductions in bitrate from conventional two-dimensional (2D) SPIHT for the same reconstruction PSNR, while retaining the desirables features of rate scalability and computational simplicity.

关键词： Compression SPIHT significance map video volumetric medical image Videotapes image sequences still image coding images compression Bit rate interframe Sequence coding Single frame

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：