Wyniki wyszukiwania - Biblioteka Nauki

1

Public watermarking algorithm based on the polarity of DCT coefficients

100%

Yu P. , Liu B.

Image Processing & Communications

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2006

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tom Vol. 11, no 2

63-73

EN

This paper presents a novel public watermarking algorithm based on the AC coefficients distribution properties of an image's DCT transform. This method uses the signs of the DCT coefficients to represent the bit 1 and 0 respectively. Furthermore, the parameters of this scheme can be calculated since we analyze the round-off errors caused by storing a watermarked image. The experiment results show that the algorithm is effective and robust to common image processing operations, such as JPEG lossy compression, Gaussian noise attack, cropping, lowpass filter and histogram equalization.

2

Digital watermarking scheme based on curvelet transform and multiple chaotic maps

100%

Xiao Y. , Xu Y.-C. , Zhou N.-R. , Lin Z.-R.

Optica Applicata

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2023

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tom Vol. 53, nr 2

291--305

EN

The rapid development of digital products brings security issues. Digital watermarking technology is an important means to handle these problems. To enhance the imperceptibility of watermark and locate the possible tampering as well, a digital watermarking scheme based on curvelet transform is presented by combining with multiple chaotic maps. The host image is decomposed into three parts, i.e., coarse layer, detail layer and fine layer, with curvelet transform, and a robust watermark is embedded into the coarse layer for copyright protection of digital products. In addition, an authentication watermark is embedded into the fine layer to detect and locate the illegal changes. Simulation results show that the proposed digital watermarking scheme possesses acceptable robustness and security.

3

Watermarking software in practical applications

100%

Lipiński P.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2011

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tom Vol. 59, nr 1

21-25

EN

In the recent years, several digital watermarking applications have been developed for copyright protection of digital images. In this article we have tested how they perform in practical applications. We have identified the most common operations performed by professional photographers and web developers, and tested the robustness of watermarks embedded using the applications for copyright watermarking. Our aim was to prove that commercially available software does not meet the requirements of photography and web industry. We have also identified areas in which the software should be improved in order to meet current and future requirements of the industry.

4

On domain selection for additive, blind image watermarking

100%

Lipiński P.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2012

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tom Vol. 60, nr 2

317-321

EN

Recently, a variety of digital watermarking schemes have been developed for copyright protection of digital images. In robust watermarking, which is used in copyright protection, transform-based algorithms are used to ensure resilience of the watermark to common signal processing attacks. The most frequently used watermarking algorithms for additive watermark embedding involve DCT, DFT, SVD and DWT domains. In this article we verify which domain is optimal for robust, the additive watermark embedding scheme. We demonstrate that in additive watermark embedding the embedding domain plays more important role than the embedding formula.

5

Authentication in VoIP Telephony with Use of the Echo Hiding Method

100%

Rachoń J. , Piotrkowski Z. , Gajewski P.

Journal of Telecommunications and Information Technology

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2011

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tom nr 1

17-21

EN

The paper describes the method intended to authenticate identity of a VoIP subscriber with use of the data hiding technique that is specifically implemented by means of the echo hiding method. The scope includes presentation of experimental results related to transmission of information via a hidden channel with use of the SIP/SDP signalling protocol as well as results of subjective assessment on quality of a signal with an embedded watermark.

6

Odporność graficznych znaków wodnych na wybrane ataki

100%

Lazoryszczak M. , Boryszek P.

Metody Informatyki Stosowanej

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2007

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tom nr 2(Tom 12)

89-94

PL

W niniejszym artykule nie przedstawiono rozmyślnych działań mających na celu usunięcie bądź zatarcie znaku wodnego, natomiast skupiono się przede wszystkim na atakach wykorzystujących powszechne przekształcenia o z góry dobranych parametrach. Wyniki mogą pozostawiać jednak zbyt wiele do życzenia w kwestii odporności znaków wodnych i ich praktycznego, skutecznego wykorzystania, otwierając tym samym pole do dalszych badań.

EN

Digital watermarking is one of intellectual properties protection methods. It could protect several media. However the most popular are graphics and sound. This paper shortly presents selected, well known methods of watermarking of the digital images and their level of immunity to the different attacks. First of all these attacks are typical transformations such as tossy compression, different filtrations etc. A combined attack is also introduced. This attack consists of some usual transformation usually used separately. But in the real world the images are often changed many times in many ways.

7

Hybrid watermarking scheme based on singular value decomposition ghost imaging

100%

Wu J.-Y. , Huang W.-L. , Wen R.-H. , Gong L.-H.

Optica Applicata

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2020

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tom Vol. 50, nr 4

633--647

EN

A hybrid watermarking algorithm with an optical watermark image based on singular value decomposition (SVD) ghost imaging is designed. Simultaneously, the blended watermarking algorithm is designed based on 4-level discrete wavelet transform (DWT), discrete cosine transform (DCT) and singular value decomposition (SVD). The 4-level diagonal sub-band image is obtained by performing 4-level two-dimensional wavelet transform on the original image, and the coefficient matrix is produced by applying the discrete cosine transform on the 4-level diagonal sub-band image. Then, three matrices are obtained by performing the singular value decomposition on the coefficient matrix. In addition, the optical watermark image is encrypted by an SVD ghost imaging system. The system could generate a secret key, and unauthorized users could not decrypt and reconstruct the original watermark image without this key. Later the encrypted watermark image is generated into the other three matrices by singular value decomposition. Afterwards, the encrypted watermark is embedded in the host image by mutual operation of different matrices in the algorithm. Simulation results validate the feasibility of the proposed hybrid watermarking scheme.

8

Improving Quality of Watermarked Medical Images Using Symmetric Dilated Convolution Neural Networks

88%

Pulgam N. D. , Shinde S. K.

Journal of Telecommunications and Information Technology

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2023

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tom nr 2

46--52

EN

Rapid development of online medical technologies raises questions about the security of the patient’s medical data.When patient records are encrypted and labeled with a watermark, they may be exchanged securely online. In order to avoid geometrical attacks aiming to steal the information, image quality must be maintained and patient data must be appropriately extracted from the encoded image. To ensure that watermarked images are more resistant to attacks (e.g. additive noise or geometric attacks), diﬀerent watermarking methods have been invented in the past. Additive noise causes visual distortion and render the potentially harmful diseases more diﬃcult to diagnose and analyze. Consequently, denoising is an important pre-processing method for obtaining superior outcomes in terms of clarity and noise reduction and allows to improve the quality of damaged medical images. Therefore, various publications have been studied to understand the denoising methods used to improve image quality. The ﬁndings indicate that deep learning and neural networks have recently contributed considerably to the advancement of image processing techniques. Consequently, a system has been created that makes use of machine learning to enhance the quality of damaged images and to facilitate the process of identifying speciﬁc diseases. Images, damaged in the course of an assault, are denoised using the suggested technique relying on a symmetric dilated convolution neural network. This improves the system’s resilience and establishes a secure environment for the exchange of data while maintaining secrecy.

9

Security issues on digital watermarking algorithms

88%

Wójtowicz W. , Ogiela M. R.

Annales Universitatis Mariae Curie-Skłodowska. Sectio AI, Informatica

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2012

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tom Vol. 12, no. 4

123--139

EN

This paper gives a general introduction to the digital watermarking procedures and their security aspects. The first issue is to clarify unifying and differentiating properties of steganography and watermarking. Then the most important aspects of digital watermarking are reviewed by studying application, requirement and design problems. We put emphasis on the importance of digital watermark as an effective technology to protect intellectual property rights and legitimate use of digital images. In the paper we provide an overview of the most popular digital watermarking methods for still images available today. The watermarking algorithms are divided into two major categories of spatial and transform domains. Because of outstanding robustness and imperceptibility the transform domain algorithms are the mainstream of research. Popular transforms of images include the DFT (Discrete Fourier Transform) ([1, 2, 3, 4, 5]), DCT (Discrete Cosine Transform) ([1, 3, 6, 5]) and DWT (Discrete Wavelet Transform) ([1, 3, 4, 7, 6, 5]). In the paper we emphasize the advantageous features of DWT such as local time-frequency and multi-scale analysis, preserving the quality of host image and ensuring high robustness of watermark. Finally, we present three algorithms which are based on the combination of DWT and some other transformations like DFT ([4]), DCT ([6]) and the Arnold transform ([7, 6]). Finally, we discuss security requirements and possible attacks on the watermarking systems.

10

A robust SVD-based image watermarking using a multi-objective particle swarm optimization

88%

Loukhaoukha K. , Nabti M. , Zebbiche K.

Opto-Electronics Review

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2014

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tom Vol. 22, No. 1

45-54

EN

The major objective in developing a robust digital watermarking algorithm is to obtain the highest possible robustness without losing the visual imperceptibility. To achieve this objective, we proposed in this paper an optimal image watermarking scheme using multi-objective particle swarm optimization (MOPSO) and singular value decomposition (SVD) in wavelet domain. Having decomposed the original image into ten sub-bands, singular value decomposition is applied to a chosen detail sub-band. Then, the singular values of the chosen sub-band are modified by multiple scaling factors (MSF) to embed the singular values of watermark image. Various combinations of multiple scaling factors are possible, and it is difficult to obtain optimal solutions. Thus, in order to achieve the highest possible robustness and imperceptibility, multi-objective optimization of the multiple scaling factors is necessary. This work employs particle swarm optimization to obtain optimum multiple scaling factors. Experimental results of the proposed approach show both the significant improvement in term of imperceptibility and robustness under various attacks.

11

An improved self-embedding algorithm: robust protection against lossy compression attacks in digital image watermarking

88%

Yogarajah P. , Condell J. , Curran K. , Cheddad K. , Mckevitt P.

Image Processing & Communications

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2010

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tom Vol. 15, no 1

47-57

EN

Watermarking is the process of embedding watermarks into an image such that the embedded watermark can be extracted later. Lossy compression attacks in digital water-marking are one of the major issues in digital watermarking. Cheddad et al. proposed a robust secured self-embedding method which is resistant to a certain amount of JPEG compression. Our experimental results show that the self-embedding method is resistant to JPEG compression attacks and not resistant to other lossy compression attacks such as Block Truncation Coding (ETC) and Singular Value Decomposition (SVD). Therefore we improved Cheddad et al's. method to give better protection against ETC and SVD compression attacks.

12

Digital watermarking based on error correction coding technique

75%

Niu X. , Lu Z. , Sun S.

Image Processing & Communications

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2000

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tom Vol. 6, no 1-2

23-28

EN

In this paper, a method of embedding a digital watermark into an image is proposed. By taking advantage of zerotree in the rearranged DCT coeffcients for watermarking, the algorithms can extract the watermark without original image. To enhance the robustness of watermarking, the watermark information is coded by error correction coding of Hamming code in our algorithm. Experimental results show that the proposed techniques successfully survive some image processing operations and the lossy compression techniques such as Joint Photographic Experts Group (JPEG).

13

Evaluating regions for digital watermarking with pixel impact factor and quantization in spatial domain

75%

Żurawski C.

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2014

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tom nr 4

73--76

EN

In this article I propose a novel usage of Pixel Impact Factor model to estimate regions for embedding digital watermark in image. Watermarking is performed in spatial domain, with usage of quantization methods. Using different quantization levels allow me to introduce relationship of Pixel Impact Factor and watermark capacity.

PL

W tym artykule proponuję nowe podejście do wyszukiwania regionów do osadzania znaku wodnego w obrazie. Osadzanie wykonywane jest w dziedzinie przestrzennej, z użyciem metod kwantyzacji. Użycie różnych poziomów kwantyzacji pozwala wskazać na związek pomiędzy współczynnikami ‘Pixel Impact Factor’ oraz pojemnością cyfrowych znaków wodnych.

14

Resilience of selected digital watermarking algorithms to transformation, distortion and compression

63%

Woda M. , Czemarmazowicz M.

Studia Informatica

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2017

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tom Vol. 38, nr 3

145--156

PL

Praca dotyczy analizy porównawczej podpisywania obrazów cyfrowych przy użyciu cyfrowych znaków wodnych. W części badawczej przedstawiono narzędzia, testy oraz wyniki przeprowadzonych testów odporności cyfrowych znaków wodnych na przekształcenia, zniekształcenia i kompresję. W zakończeniu omówiono wnioski oraz wskazano kierunki dalszych badań.

EN

The work concerns a comparative analysis of well-known and widely used signing digital images using digital watermarks. It consists of three parts: the introduction to the subject matter, description of algorithms, and the research part. In the research part: tools, tests and results of digital watermarks resistance on the transformation, distortion and compression are presented. In conclusion, the findings are discussed and directions for further research identified.

15

Usuwanie cyfrowych znaków wodnych na podstawie cech autokorelacji obrazu

63%

Bogumił D.

Elektronizacja : podzespoły i zastosowania elektroniki

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2003

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tom Vol. 23, nr 9

17-20

PL

W artykule ujawniono wrażliwość niektórych systemów cyfrowych znaków wodnych na atak bazujący na analizie wartości funkcji autokorelacji obrazu. Przedstawiona metoda pozwala wyodrębnić i całkowicie usunąć znak wodny w sytuacji, gdy dostępny jest tylko obraz ze znakiem. Na atak narażone są m. in. te szeroko rozpowszechnione systemy, które wstawiają do kolejnych bloków obrazu ten sam znak wodny.

EN

In this paper we present a weakness of some watermarking techniques that use autocorrelation function properties. Many widespread systems, both academic and commercial, that insert the same watermark into consecutive image blocks, are vulnerable to this attack. The proposed attack allows separating and removing a watermark on the basis of a watermarked image analysis, without knowledge a of watermarking key.