In response to the growing demand for computation and storage, and increasing vulnerabilities to attacks, maintaining image security and integrity remains a critical challenge. This paper introduces a novel, lossless ...
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In response to the growing demand for computation and storage, and increasing vulnerabilities to attacks, maintaining image security and integrity remains a critical challenge. This paper introduces a novel, lossless image compression algorithm integrating improved fractal coding and a robust encryption method based on a new hyperchaotic system, irregular block permutation, and non-adjacent diffusion. The proposed 4D hyperchaotic system exhibits a wider chaotic range and more complex dynamics than existing systems, generating high-quality pseudo-random sequences for enhanced encryption security. Additionally, a lossless multi-directional delta encoding and segment run-length encoding method, utilizing variable-grid fractal coding, are developed to optimize data compression and preserve information integrity. Furthermore, a Tetris-based permutation and 2D nonlinear diffusion technique is proposed, using irregular patterns and non-adjacent double diffusion to resist various attacks. Experiments show that compared with other compression and encryption algorithms, the proposed algorithm has a higher compression ratio, strong sensitivity to key or plaintext, and can resist various attacks, such as brute-force attacks, statistical attacks and differentiable attacks.
fractal techniques have been used by a number of authors (Barnsley and Sloan, 1988;Jacquin, 1989) to code monochrome images. In this paper we investigate a version of the technique proposed by Jacquin. A number of ext...
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fractal techniques have been used by a number of authors (Barnsley and Sloan, 1988;Jacquin, 1989) to code monochrome images. In this paper we investigate a version of the technique proposed by Jacquin. A number of extensions are made to his coding scheme, and in particular it is shown that one can considerably weaken the requirement on contractivity leading to a coding scheme which preserves high frequencies much better than that proposed by Jacquin.
Main objective of the proposed work is to develop an approach for video coding based on fractal coding using the weighted finite automata (WFA). The proposed work only focuses on reducing the encoding time as this is ...
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Main objective of the proposed work is to develop an approach for video coding based on fractal coding using the weighted finite automata (WFA). The proposed work only focuses on reducing the encoding time as this is the basic limitation why the fractal coding not becomes the practical reality. WFA is used for the coding as it behaves like the fractal coding (FC). WFA represents an image based on the idea of fractal that the image has self-similarity in itself. The plane WFA (applied on every frame), and Plane FC (applied on every frame) coding approaches are compared with each other. The experimentations are carried out on the standard uncompressed video databases, namely, Traffic, Paris, Bus, Akiyo, Mobile, Suzie etc. and on the recorded video, namely, Geometry and Circle. Developed approaches are compared on the basis of performance evaluation parameters, namely, encoding time, decoding time, compression ratio, compression percentage, bits per pixel and Peak Signal to Noise Ratio (PSNR). Though the initial number of states is 256 for every frame of all the types of videos, but we got the different number of states for different frames and it is quite obvious due to minimality of constructed WFA for respective frame. Based on the obtained results, it is observed that the number of states is more in videos namely, Traffic, Bus, Paris, Mobile, and Akiyo, therefore the reconstructed video quality is good in comparison with other videos namely, Circle, Suzie, and Geometry.
We propose a new image compression scheme based on fractal coding of the coefficients of a wavelet transform, in order to take into account the self-similarity observed in each subband. The original image is first dec...
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We propose a new image compression scheme based on fractal coding of the coefficients of a wavelet transform, in order to take into account the self-similarity observed in each subband. The original image is first decomposed into subbands containing information in different spatial directions and at different scales, using an orthogonal wavelet-generated filter bank. Subbands are encoded using local iterated function systems (LIFS), with range and domain blocks presenting horizontal or vertical directionalities. Their sizes are defined according to the correlation lengths and resolution of each subband. The edge degradation and the blocking effects encountered at low bit-rates using conventional LIES algorithm are reduced with this approach. The computation complexity is also greatly decreased by a 12:1 factor in comparison to fractal coding of the full resolution image. The proposed method is applied to standard test images. The comparison with other fractal coding approaches and with JPEG shows an important increase in terms of PPSNR/bit-rate. Especially for images presenting a privileged directionality, the use of adaptive partitions results in about 3 dB improvement in PPSNR. We also discuss the distorsion versus rate improvement obtained on high-frequency subbands when fractal coding instead of pyramidal vector quantization is used. Our approach achieves a real gain in PPSNR for low bit-rates between 0.3 and 1.2 bpp. (C) 1998 Elsevier Science B.V. All rights reserved.
Biometric image hashing techniques have been widely studied and seen progressive advancements. However, only a handful of available solutions provide two-factor cancelability while simultaneously satisfying the tradeo...
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Biometric image hashing techniques have been widely studied and seen progressive advancements. However, only a handful of available solutions provide two-factor cancelability while simultaneously satisfying the tradeoff among all criteria of template protection mechanisms. In this paper, we propose a novel scheme for generating a secure and robust hash from a fingerprint image using Fourier-Mellin transform and fractal coding. First, due to its invariance property, Fourier-Mellin transform is incorporated into the domain fingerprint minutiae blocks to provide feature alignment, therein generating a fixed-length minutiae representation for comparison. Then, dimensionality reduction and texture compression are exploited using fractal coding to generate a robust and compact hash for improved security and recognition. The experimental results demonstrate a favorable recognition performance on benchmarked state-of-the-art schemes from FVC2002 and FVC2004 fingerprint databases. The analyses prove our method's robustness and resiliency to security and privacy attacks. Our method also satisfies the revocability and unlinkability criteria of cancelable biometrics.
In this paper, we investigate the application of fractal concept to the coding of medical images, taking into account the self-similarity at different scales. The approach proposed by Jacquin is very flexible, enablin...
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ISBN:
(纸本)0819420824
In this paper, we investigate the application of fractal concept to the coding of medical images, taking into account the self-similarity at different scales. The approach proposed by Jacquin is very flexible, enabling us to optimize different steps of the associated algorithm. We remark that the choice of the distance used to measure the self-similarity between the range block Ri and the estimated range block Ri is essential to the algorithm. In fact, the choice of the metric determines the optimal parameters of the affine transformation. In our study, we propose two metrics, L2 and L(infinity ) and compare their performances. We also develop a simple fast decoding scheme, necessary for a clinical use. This paper addresses the adaptation of the fractal compression algorithm to medical image modalities. We present the results obtained with two image data bases (numerized mammograms and x-ray angiograms). A comparison with JPEG results shows the improvement with our technique, particularly for low bit rates.
Aiming at content-based image retrieval (CBIR) in fractal domain, this paper puts forward a fast fractal encoding method to extract image features, which is based on a novel non-searching and adaptive quadtree divisio...
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Aiming at content-based image retrieval (CBIR) in fractal domain, this paper puts forward a fast fractal encoding method to extract image features, which is based on a novel non-searching and adaptive quadtree division. As a result, it enhances fractal coding speed sharply, only needs 0.0485 seconds on average for a 256 x 256 image and is approximately 70 times faster than algorithm in addition to good reconstructed image quality. Furthermore, this paper improves image matching algorithm, consequently enhancing the accuracy of query results. In addition, we present a method to further accelerate image retrieval based on the analysis to fractal codes distance and number. Experimental results show that our proposed method is performs highly in retrieval speed and feasible in retrieval accuracy.
Information hiding researchers have been exploring techniques to improve the security of transmitting sensitive data through an unsecured channel. This paper proposes an audio steganography model for secure audio tran...
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Information hiding researchers have been exploring techniques to improve the security of transmitting sensitive data through an unsecured channel. This paper proposes an audio steganography model for secure audio transmission during communication based on fractal coding and a chaotic least significant bit or also known as HASFC. This model contributes to enhancing the hiding capacity and preserving the statistical transparency and security. The HASFC model manages to embed secret audio into a cover audio with the same size. In order to achieve this result, fractal coding is adopted which produces high compression ratio with the acceptable reconstructed signal. The chaotic map is used to randomly select the cover samples for embedding and its initial parameters are utilized as a secret key to enhancing the security of the proposed model. Unlike the existing audio steganography schemes, The HASFC model outperforms related studies by improving the hiding capacity up to 30% and maintaining the transparency of stego audio with average values of SNR at 70.4, PRD at 0.0002 and SDG at 4.7. Moreover, the model also shows resistance against brute-force attack and statistical analysis.
This paper presents an efficient fractal coding scheme for color images and demonstrates its experimental results. The proposed fractal coding scheme utilizes the correlation between a luminance component (Y) and two ...
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ISBN:
(纸本)0819450235
This paper presents an efficient fractal coding scheme for color images and demonstrates its experimental results. The proposed fractal coding scheme utilizes the correlation between a luminance component (Y) and two color difference components (Cr and Cb) of an input color image. The Y, Cr and Cb components are first decomposed to low and high frequency sub-band images. fractal block coding is performed only on the lowest frequency sub-band images of Y, Cr and Cb. The other high frequency sub-band images are encoded by vector quantization (VQ). In the fractal coding process for Y, each range block is encoded by a set of contractive affine transformations of its correspondent domain block. For Cr and Cb, on the other hand, only the range block average values are coded. The other fractal coded data of the correspondent range block of Y are applied also to Cr and Cb. The computer simulation experimental results show that the coded and decoded color images obtained by the proposed scheme give higher SNR values and better image qualities compared to the conventional fractal coding scheme and JPEG.
Securing confidential information over an unsecured communication channel and environment has become an essential aspect. This paper proposes high-capacity audio steganography model based on fractal coding and uniform...
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Securing confidential information over an unsecured communication channel and environment has become an essential aspect. This paper proposes high-capacity audio steganography model based on fractal coding and uniform coefficient modulation, which will be called as HASFC, that simultaneously adjusts the data hiding requirements by increasing the hiding capacity while maintaining the transparency and robustness. HASFC model is based on cover-secret mapping, uniform coefficients modulation and hybrid chaotic map techniques in the transform domain using lifting wavelet. The efficiency of the proposed model is evaluated using a set of experiments, and the audio files are selected from the GTZAN dataset. The empirical findings show improvement in hiding capacity by 30% in comparison with similar techniques in the wavelet domain. Moreover, the transparency is preserved with 50 dB SNR and 4.8 SDG, on average. Furthermore, the proposed model is robust to some signal processing attacks and steganalysis using statistical methods such as the fourth first moment and histogram error ratio. The results signify that the proposed model has notably enhanced the performance of the audio steganography comparing with the related works.
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