检索结果-内蒙古大学图书馆

5th International Congress on image and Signal Processing (CISP)

作者： Zhang, Aihua Yang, Pei Nanjing Univ Posts & Telecommun Nanjing Jiangsu Peoples R China

ISBN: (纸本)9781467309646

The fractal image coding algorithm is a kind of brand-new coding algorithm, which uses the self-similarity of the image to realize the image data's compression. But for each range block, searching out the best matched domain block is a extremely time-consuming thing. A faster encoding algorithm is thus proposed in this paper. The proposed algorithm uses an inequality linking the root-mean-square(RMS) and the relative error, sets up a kick-out condition based on the relative error to avoid the excessive searching, and thus the remaining domain blocks could be discarded, so its runtime is significantly shortened. The simulation results on 2 test images with different complexities demonstrate that the proposed scheme could averagely achieve the speed-up of 32 times as the baseline fractal algorithm with full searching, while it gives an insignificant degradation in the subjective quality of the decoded image.

关键词： image compression fractal image encoding relative error kick-out condition

来源：评论

学校读者我要写书评

暂无评论

Robust Search Method for fractal image encoding Using Fringe Based Property 12

Robust Search Method for Fractal Image Encoding Using Fringe...

引用

12 IEEE Int C Elect Energy Env Communications Computer Control

作者： Aggarwal, Indu Gupta, Richa Amity Univ ASET CSE Dept Noida India

ISBN: (纸本)9781467365406

In this paper, the fringe property based fractal image encoding is introduced to reduce the encoding time. The main drawback of fractal encoding is high encoding time. There have been various researches carried out to overcome the limitation of fractal encoding and to speed up the encoder. A remarkable improvement was made by neighborhood region search strategies which classify the image blocks on the basis of some feature vectors of image to restrict the region for best matching pair of domain and range and also reduces the search complexity to logarithmic time. The neighborhood search strategy used in spatial domain reduces the encoding time from linear time to logarithmic time. The same principle was followed by neighborhood search in DCT based lowest frequency domain by reducing the search space to gather image blocks with similar fringe shapes. In addition to spatial domain based approach, it take less time to map the range blocks and domain blocks which consecutively consumes lesser time to encode image. The proposed algorithm used k-nearest neighbor search to find the similar fringe shaped range and domain blocks to be mapped on the basis of DCT lowest coefficients in horizontal and vertical directions and then using similarity measure;the virtual codebook was prepared to encode the image and then decoded the image using averaging of pixels of selected domains. The proposed approach gave high PSNR value, high compression ratio and reduced MSE computations with little decay in image quality which is acceptable.

关键词： DCT fringe property fractal image encoding k-neighborhood search

来源：评论

学校读者我要写书评

暂无评论

Hybrid encoding analysis of fractal image compression method based on wavelet transform

Hybrid encoding analysis of fractal image compression method...

引用

7th International Conference on Machine Learning and Cybernetics

作者： Xu, Xiao-Yan Chen, Philip Dai, Juan Shanghai Maritime Univ Dept Elect Engn Shanghai 200135 Peoples R China Univ Texas San Antonio Elect & Comp Engn Dept San Antonio TX USA Kunming Univ Sci & Technol Fac Mech & Elect Eng Kunming 650093 Peoples R China

ISBN: (纸本)9781424420957

Firstly, the principle and characteristics of fractal image encoding is introduced, and a kind of hybrid image compression method is developed for the improvement of image compression quality, which is the combination of fractal image encoding and wavelet decomposition. In the process of encoding, the image is dealt by three level wavelet decomposition, and the high frequency section of the decomposed image adopts scatheless predicting encoding, while the low frequency section adopts fractal compression encoding. In the process of decoding, the high frequency section carries out scatheless predicting decoding, while the low frequency section is decoded to ITS (iterative function system) code which is used for subimage reconstruction. The experimental result shows that the application of the designed hybrid image compression method can increase the signal-to-noise ratio of an image while the high compression ratio of the image is guaranteed.

关键词： fractal image encoding IFS (iterative function system) wavelet decomposition hybrid encoding

来源：评论

学校读者我要写书评

暂无评论

HYBRID encoding ANALYSIS OF fractal image COMPRESSION METHOD BASED ON WAVELET TRANSFORM

HYBRID ENCODING ANALYSIS OF FRACTAL IMAGE COMPRESSION METHOD...

引用

2008 International Conference on Machine Learning and Cybernetics(2008机器学习与控制论国际会议)

作者： XIAO-YAN XU PHILIP CHEN JUAN DAI Electrical Engineering Department Shanghai Maritime University Shanghai 200135 China Electrical and Computer Engineering Department University of Texas at San Antonio TX 78249 U.S. Faculty of Mechanical and Electrical Eng. Kunming University of Science and Technology Kunming 650

Firstly, the principle and characteristics of fractal image encoding is introduced, and a kind of hybrid image compression method is developed for the improvement of image compression quality, which is the combination of fractal image encoding and wavelet decomposition. In the process of encoding, the image is dealt by three level wavelet decomposition, and the high frequency section of the decomposed image adopts scatheless predicting encoding, while the low frequency section adopts fractal compression encoding. In the process of decoding, the high frequency section carries out scatheless predicting decoding, while the low frequency section is decoded to IFS (iterative function system) code which is used for subimage reconstruction. The experimental result shows that the application of the designed hybrid image compression method can increase the signal-to-noise ratio of an image while the high compression ratio of the image is guaranteed.

关键词： fractal image encoding IFS (Iterative Function System) Wavelet Decomposition Hybrid encoding

来源：评论

学校读者我要写书评

暂无评论

Adaptive approximate nearest neighbor search for fractal image compression

引用

IEEE TRANSACTIONS ON image PROCESSING 2002年第6期11卷 605-615页

作者： Tong, CS Wong, M Hong Kong Baptist Dept Math Kowloon Hong Kong Peoples R China

fractal image encoding is a computationally intensive method of compression due to its need to find the best match between image subblocks by repeatedly searching a large virtual codebook constructed from the image under compression. One of the most innovative and promising approaches to speed up the encoding is to convert the range-domain block matching problem to a nearest neighbor search problem. This paper presents an improved formulation of approximate nearest neighbor search based on orthogonal projection and pre-quantization of the fractal transform parameters. Furthermore, an optimal adaptive scheme is derived for the approximate search parameter to further enhance the performance of the new algorithm. Experimental results showed that our new technique is able to improve both the fidelity and compression ratio, while significantly reduce memory requirement and encoding time.

关键词： .collage error range blocks domain pool domain block fractal image encoding Adaptive approximate

来源：评论

学校读者我要写书评

暂无评论

fractal image COMPRESSION BASED ON MATCHING ERROR THRESHOLD

引用

fractalS-COMPLEX GEOMETRY PATTERNS AND SCALING IN NATURE AND SOCIETY 2009年第1期17卷 109-115页

作者： Wang, Xing-Yuan Zou, Li-Xian Dalian Univ Technol Sch Elect & Informat Engn Dept Comp Dalian 116024 Liaoning Prov Peoples R China

This paper proposes a fractal image encoding algorithm based on matching error threshold: first the authors set up two kick-out conditions to reduce the capacity of the codebook, and then set up a matching threshold when searching the best matching blocks, which can shorten its runtime greatly. Meanwhile, the authors discard the isometric transformations that are mentioned in most literatures, because the usage of the isometric transformations only increase the computational complexity, the same or even better reconstructed image can achieve through reducing the sliding step of producing domain blocks. Experimental results indicate that the proposed algorithm can both shorten the encoding time greatly and achieve the same or better reconstructed image quality as compared with the basic fractal encoding algorithm with full search.

关键词： fractal fractal image encoding image Compression Matching Error

来源：评论

学校读者我要写书评

暂无评论

A hardware architecture for real-time image compression using a searchless fractal image coding method

引用

JOURNAL OF REAL-TIME image PROCESSING 2007年第3期1卷 225-237页

作者： Jackson, David Jeff Ren, Haichen Wu, Xianwei Ricks, Kenneth G. Univ Alabama Dept Elect & Comp Engn Tuscaloosa AL 35487 USA

In this paper we present a novel hardware architecture for real-time image compression implementing a fast, searchless iterated function system (SIFS) fractal coding method. In the proposed method and corresponding hardware architecture, domain blocks are fixed to a spatially neighboring area of range blocks in a manner similar to that given by Furao and Hasegawa. A quadtree structure, covering from 32 x 32 blocks down to 2 x 2 blocks, and even to single pixels, is used for partitioning. Coding of 2 x 2 blocks and single pixels is unique among current fractal coders. The hardware architecture contains units for domain construction, zig-zag transforms, range and domain mean computation, and a parallel domain-range match capable of concurrently generating a fractal code for all quadtree levels. With this efficient, parallel hardware architecture, the fractal encoding speed is improved dramatically. Additionally, attained compression performance remains comparable to traditional search-based and other searchless methods. Experimental results, with the proposed hardware architecture implemented on an Altera APEX20K FPGA, show that the fractal encoder can encode a 512 x 512 x 8 image in approximately 8.36 ms operating at 32.05 MHz. Therefore, this architecture is seen as a feasible solution to real-time fractal image compression.

关键词： fractal image encoding Quadtree Searchless Real-time image compression

来源：评论

学校读者我要写书评

暂无评论

image coding method based on fractal prediction

Image coding method based on fractal prediction

引用

Conference on Visual Information Processing VI

作者： Zhang, ZB Zhu, GX Zhu, YT Cao, HQ Huazhong Univ. of Science and Technology (China)

ISBN: (纸本)0819424897

A novel image compression method is proposed, in this paper, based on fractal prediction. The original image is decimated into a smaller image which is encoded with fractal method based on the fact that the smaller the size of an image, the shorter the time of encoding. A fractal prediction is obtained by decoding an image, at a same size as the original image, from the fractal codes of the decimated image. The prediction image is subtracted from the original image to arrive at a difference image, which is encoded based on DCT for error correction. Experimental results show that this algorithm is faster that typical fractal image coding methods, and the reconstructed image have good fidelities to the original image at relatively high compression. This method combines the advantages of fractal coding and JPEG coding together.

关键词： fractal image encoding fractal image compression image coding image compression JPEG DCT fractal interpolation fractal prediction fractal IFS

来源：评论

学校读者我要写书评

暂无评论

A New Simple Fast DCT Coefficients-Based Metric Operation for fractal image Compression

A New Simple Fast DCT Coefficients-Based Metric Operation fo...

引用

2nd International Conference on Computer Engineering and Applications

作者： Kiani, Korush Jaferzadeh, Keyvan Rezaei, Hadi Gholami, Samaneh Semnan Univ Elect & Comp Eng Dept Semnan Iran univ Coll Nabi Akram Tabriz Iran

ISBN: (纸本)9780769539829

In fractal image compression the encoding step is computationally expensive, because every range block must be compared to all domain blocks in the codebook to find the best-matched one during the coding procedure. In this paper, a fast fractal encoding algorithm using DCT coefficients-based Metric operation is proposed. Simulation results show that the runtime of the proposed algorithm is reduced greatly compared to the existing methods. At the same time, the new algorithm also achieved high compression ratio.

关键词： component fractal image compression DCT transformation fractal image encoding Metric

来源：评论

学校读者我要写书评

暂无评论

Suboptimal fractal coding scheme using iterative transformation

引用

OPTICAL ENGINEERING 2001年第5期40卷 703-712页

作者： Kang, HS Chung, JW Hyundai Co Ltd Seoul South Korea Serome Technol Inc R&D Ctr Seoul South Korea

This paper presents a new fractal coding scheme to find a suboptimal transformation by performing an iterative encoding process. The optimal transformation can be defined as the transformation generating the closest attractor to an original image. Unfortunately, it is impossible in practice to find the optimal transformation, due to the heavy computational burden. In this paper, however, by means of some new theorems related with contractive transformations and attractors, it is shown that for some specific cases the optimal or suboptimal transformations can be obtained. The proposed method obtains a suboptimal transformation by performing iterative processes as is done in decoding. Thus, it requires more computation than the conventional method, but it improves the image quality. For a simple case where the optimal transformation can actually be found, the proposed method is experimentally evaluated against both the optimal method and the conventional method. For a general case where the optimal transformation is unavailable due to heavy computational complexity, the proposed method is also evaluated in comparison with the conventional method. (C) 2001 Society of Photo-Optical Instrumentation Engineers.

关键词： fractal image encoding optimal transformation iterative coding

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：