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Still Color Image Coding Based on Fractal Approximation of 2 D DCT
静止彩色图象压缩编码技术

Zhu Yanqiu,Chu Lianyu,Chen Hexin,
朱艳秋
,陈贺新

中国图象图形学报 , 1997,
Abstract: In the field of still color image coding,there is a widespread problem that the correlation among components is not fully explored. In this paper,emphasis is placed on the high structural self similarity among components of a color image and a fractal coding method based on 2 D DCT is promoted. In this method,after reducing the redundancy within each component by 2 D DCT,the redundancy among components is further reduced by fractal coding. Simulation results demonstrate a better performance of this method than that of the JPEG method.
Secure Fractal Image Coding  [PDF]
Shiguo Lian
Computer Science , 2007,
Abstract: In recent work, various fractal image coding methods are reported, which adopt the self-similarity of images to compress the size of images. However, till now, no solutions for the security of fractal encoded images have been provided. In this paper, a secure fractal image coding scheme is proposed and evaluated, which encrypts some of the fractal parameters during fractal encoding, and thus, produces the encrypted and encoded image. The encrypted image can only be recovered by the correct key. To keep secure and efficient, only the suitable parameters are selected and encrypted through in-vestigating the properties of various fractal parameters, including parameter space, parameter distribu-tion and parameter sensitivity. The encryption process does not change the file format, keeps secure in perception, and costs little time or computational resources. These properties make it suitable for secure image encoding or transmission.
Fractal Image Coding with Digital Watermarks
M. Candik,D. Levicky,Z. Klenovicova
Radioengineering , 2000,
Abstract: In this paper are presented some results of implementation of digitalwatermarking methods into image coding based on fractal principles. Thepaper focuses on two possible approaches of embedding digitalwatermarks into fractal code of images - embedding digital watermarksinto parameters for position of similar blocks and coefficients ofblock similarity. Both algorithms were analyzed and verified on grayscale static images.
Approximation Error Based Suitable Domain Search for Fractal Image Compression
Vijayshri Chaurasia,Ajay Somkuwar
International Journal of Engineering Science and Technology , 2010,
Abstract: Fractal Image compression is a very advantageous technique in the field of image compression. The coding phase of this technique is very time consuming because of computational expenses of suitable domain search. In this paper we have proposed an approximation error based speed-up technique with the use of feature extraction. Proposed scheme reduces the number of range-domain comparisons with significant amount and gives improved time performance.
Some Modifications of Fractal Image Coding
D. Levicky,M. Candik,R. Pundzak
Radioengineering , 1999,
Abstract: In this paper some modifications of fractal image coding are presented. Proposed methods are based on correlation coefficients computing as an alternative approach to searching of similarity between blocks. The convergence speed of decoding process is faster then convergence speed of standard method. The convergence process with modified start conditions of decoding process are analysed and verified on gray scale static images too.
Fractal Image Coding
分形图象编码

He Aijun,Ma Zhengming,
何爱军
,马争鸣

中国图象图形学报 , 1999,
Abstract: This is an overview on fractal image coding. On the base of collecting and reading related documents, we describe the current research status of fractal image coding and make a remark on its prospect.
Several Remarks on Fractal Image Block Coding
L. Dedera,J. Chmurny
Radioengineering , 1997,
Abstract: In this paper the dependence of PSNR on the size of both a codebook pool and range blocks is compared. The statistical properties of the values of transformation coefficients and distances between coded range blocks and optimal domain blocks in the fractal image block coding scheme are discussed.
Fractal coding based on image local fractal dimension
Conci, Aura;Aquino, Felipe R.;
Computational & Applied Mathematics , 2005,
Abstract: fractal codification of images is based on self-similar and self-affine sets. the codification process consists of construction of an operator which will represent the image to be encoded. if a complicated picture can be represented by an operator then it will be transmitted or stored very efficiently. clearly, this has many applications on data compression. the great disadvantage of the automatic form of fractal compression is its encoding time. most of the time spent in construction of such operator is due on finding the best match between parts of the image to be encoded. however, since the conception of automatic fractal image compression, researches on improvement of the compression time are widespread. this work aims to provide a new idea for decrease the encoding time: a classification of image parts based on their local fractal dimension. the idea is implemented on two steps. first, a preprocessing analysis of the image identify the complexity of each image block computing its dimension. then, only parts within the same range of complexity are used for testing the better self-affine pairs, reducing the compression time. the performance of this proposition, is compared with others fractal image compression methods. the points considered are image fidelity, encoding time and amount of compression on the image file.
Fractal coding based on image local fractal dimension  [cached]
Aura Conci,Felipe R. Aquino
Computational and Applied Mathematics , 2005,
Abstract: Fractal codification of images is based on self-similar and self-affine sets. The codification process consists of construction of an operator which will represent the image to be encoded. If a complicated picture can be represented by an operator then it will be transmitted or stored very efficiently. Clearly, this has many applications on data compression. The great disadvantage of the automatic form of fractal compression is its encoding time. Most of the time spent in construction of such operator is due on finding the best match between parts of the image to be encoded. However, since the conception of automatic fractal image compression, researches on improvement of the compression time are widespread. This work aims to provide a new idea for decrease the encoding time: a classification of image parts based on their local fractal dimension. The idea is implemented on two steps. First, a preprocessing analysis of the image identify the complexity of each image block computing its dimension. Then, only parts within the same range of complexity are used for testing the better self-affine pairs, reducing the compression time. The performance of this proposition, is compared with others fractal image compression methods. The points considered are image fidelity, encoding time and amount of compression on the image file.
Comparative Study: Block Truncating Coding, Wavelet and Fractal Image Compression  [PDF]
Dinesh Gupta,Pardeep Singh,,Nivedita,Sugandha Sharma
International Journal of Computer Technology and Applications , 2012,
Abstract: We undertake a study of the performance difference of different transform coding techniques i.e. Block truncating coding, wavelet and fractal image compression. This paper focuses important features of transform coding in compression of still images, including the extent to which the quality of image is degraded by the process of compression and decompression. The above techniques have been successfully used in many applications. The techniques are compared by using the performance parameters PSNR, CR and reduced size. Images obtained with those techniques yield very good results
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