Water Marking Research Articles

A Practical BuyerSeller Watermarking Protocol based on Discrete Wavelet Transform

watermarking is the key technology of digital copyright protection. An efficient digital watermarking solution must tackle the problems of copyright protection and trace of pirate copy. Digital water marking is a promising technology to embed information as unperceivable signals in digital contents. It plays a very important role in E-commerce. Buyer-seller watermarking protocols based on Discrete Wavelet Transform (DWT) integrate multimedia watermarking and fingerprinting with cryptography, for copyright protection, piracy tracing, and privacy protection. It uses the public key encryption schemes. In this paper we propose a Practical Buyer Seller watermarking protocol based on Discrete Wavelet Transform (DWT) which is secure and flexible and gives more security from previous watermarking protocols to both buyer and seller. In this we use Public Key Infrastructure (PKI), arbitrator and watermarking certificate authority (WCA) for better security. The protocol has better security property and higher efficiency. Keywordskey infrastructure; copyright protection; Digital watermarking;

"Advanced steganographic approach for hiding encrypted secret message in LSB,LSB+1,LSB+2 and LSB+3 bits in non standard cover files"

In digital steganography normally image, audio or video files are the standard cover files or the host files for embedding secret message such as text, image, audio or video. Nath et al.(2) explored the standard method for hiding secret message inside standard cover files such as image, audio or video files. In the present work we have shown how we can hide secret message in encrypted form in some non standard cover files such as .exe, .com, .pdf, .doc, .xls, .mdb, .ppt files. However, the size of the secret message must be very small in comparison to cover file. The secret message is converted to encrypted form using MSA algorithm(2) and then we hide the encrypted message inside the non standard cover file. To hide encrypted secret message we insert the 8 bits in 2 consecutive bytes of cover file in LSB, LSB+1, LSB+2 and LSB+3 positions. This method could be very effective to hide some information in some executable file. To make the entire process secured we have introduced the password when we hide message and while encrypting the secret message we have to input some text_key. While hiding secret message in cover file we embed 1 byte information in two consecutive bytes of the cover file. There is a risk factor that it may damage the cover file in such a way that the embedded cover file may not behave in proper way as it was behaving before insertion of secret message. However, there is one advantage that we can embed more data in a cover file. We propose that our new method could be most appropriate for hiding any file in any non-standard cover file such as executable file such as .EXE or .COM file, compiler, MS-Office files, Data Base files such as .MDB, .PDF file. Our method will now give open challenge to all user that it is possible to hide any small secret message inside in any non standard cover files. The present work shows that we can hide information in almost all files except pure text or ASCII file. The only restriction is the size of secret message should be extremely small in comparison to cover file. The present method may be implemented in digital water marking in any legal electronic documents, Bank data transactions, in government sectors, in defense, in schools and colleges.

离散余弦变换域抗二次打印-扫描鲁棒零水印算法

Because the existing robust watermarking algorithms cannot involve the research of robustness against dual print-and-scan process,a robust zero-watermarking algorithm against dual print-and-scan process was proposed.The algorithm was based on the stability of the numerical relationship between each block′s direct coefficient and the average of direct coefficients form all blocks in discrete cosine transformation domain.The image was divided into non-overlapping blocks,and each block was transformed with discrete cosine transformation.Zero-watermark sequence was produced by judging the numerical relationship between each block′s direct coefficient and the average of direct coefficients form all blocks.Some tests were carried out including its robustness against single print-and-scan process,conventional signal processing after single print-and-scan process,dual print-and-scan process,and conventional signal processing after dual print-and-scan process.The results show that the proposed algorithm has excellent robustness towards those above attacks.

Advanced Steganography Algorithm using Encrypted secret message

In the present work the authors have introduced a new method for hiding any encrypted secret message inside a cover file. For encrypting secret message the authors have used new algorithm proposed by Nath et al(1). For hiding secret message we have used a method proposed by Nath et al(2). In MSA(1) method we have modified the idea of Play fair method into a new platform where we can encrypt or decrypt any file. We have introduced a new randomization method for generating the randomized key matrix to encrypt plain text file and to decrypt cipher text file. We have also introduced a new algorithm for encrypting the plain text multiple times. Our method is totally dependent on the random text_key which is to be supplied by the user. The maximum length of the text_key can be of 16 characters long and it may contain any character(ASCII code 0 to 255). We have developed an algorithm to calculate the randomization number and the encryption number from the given text_key. The size of the encryption key matrix is 16x16 and the total number of matrices can be formed from 16 x 16 is 256! which is quite large and hence if someone applies the brute force method then he/she has to give trail for 256! times which is quite absurd. Moreover the multiple encryption method makes the system further secured. For hiding secret message in the cover file we have inserted the 8 bits of each character of encrypted message file in 8 consecutive bytes of the cover file. We have introduced password for hiding data in the cover file. We propose that our new method could be most appropriate for hiding any file in any standard cover file such as image, audio, video files. Because the hidden message is encrypted hence it will be almost impossible for the intruder to unhide the actual secret message from the embedded cover file. This method may be the most secured method in digital water marking.

Comparison of Spectrum Sensing Algorithms for Cognitive Radio Systems

Cognitive radio (CR), which is proposed as a technology that utilizes the frequency resources effectively, has studied to relive scarcity of the frequency resources. CR provides opportunistically under-utilize licensed frequency to the secondary user. However, in the wireless channels, due to the effect of fading and shadowing environments, spectrum sensing performance is compromised. Besides, to detect and classify various CR systems, a novel spectrum sensing algorithm is needed. Therefore, in this paper, we proposed the spectrum sensing algorithm with water marking scheme.

可抵抗JPEG压缩的鲁棒可逆水印

A novel reversible watermarking scheme is proposed,which is robust against high-quality JPEG compression.By computing the difference between the means of two adjacent image blocks,employing it to embed the watermark,and using block histogram shifting to avoid overflow/underflow,this technique receives both losslessness and robustness.If the watermarked image does not change at all,the watermark can be extracted out correctly and the original image can be recovered losslessly.If the watermarked image is compressed to some extent,the watermark can still be correctly extracted for semi-fragile authentication.The scheme is successfully applied to three kinds of medical images and commonly used images.Experimental results show that the high visual quality of images,the pure payload,and the robustness of the proposed scheme against compression are acceptable for many applications,including semi-fragile image authentication.

웹 이미지의 저작권 보호를 위한 디지털 워터마킹 시스템

본 논문에서는 원본 이미지에 저작권자의 저작권 정보를 삽입함으로써 저작권을 보호하고 차후 불법적인 도용을 방지하기 위해, 숫자와 로고로 구성된 워터마크 생성, 삽입 및 검출, 검증 시스템을 설계 및 구현한다. 본 시스템은 콘텐츠의 특성과 저작권자의 요구에 따라 워터마크를 숫자 또는 로고로 선택해서 구성할 수 있으며, 저작권 보호에 대한 전문지식이 없는 일반관리자도 용이하게 이용할 수 있는 사용자 인터페이스를 갖추도록 설계하였다. 이러한 디지털 이미지 워터마킹의 적용을 통한 소유권 및 저작권 보호는 궁극적으로 문화콘텐츠 등의 콘텐츠 제작 의뢰자로 하여금 제작 의지를 강화하여 제작 의뢰 건수를 증가시킬 수 있을 것으로 기대된다. 【In this paper, we design and implement watermarking system which create, insert and detect watermark comprised of number or logo to protect copyright and to prevent illegal plagiarism through inserting copyrighting information of owner into the original image. In the proposed system, the number or logo as watermark is selectively inserted according to characteristics of the original contents or requirement of copyrighter. The system also has convenient user interface which general administrator who hasn't expert knowledge for the protection of copyright uses easily. Ownership and copyright protection using digital watermarking technology intensifies creating volition of clients who want to create contents such as cultural contents, Thus, we can expect increasing requests for creating contents such as cultural contents.】

基于无下采样Contourlet变换和人眼视觉系统的稳健盲水印算法

基于无下采样Contourlet变换和人眼视觉系统的稳健盲水印算法

Covert Encryption and Document Authentication using Texture Coding

With the im provem ents in the quality of Com m ercial-Off-The-Shelf (COTS) printing and scanning devices, the ability to counterfeit docum ents has becom e a widespread problem . Consequently, there has been an increasing dem and to develop digital waterm arking techniques which can be applied to both electronic and printed im ages (and docum ents) that can be authenticated, prevent unauthorized copying and withstand abuse and degradation. In this paper, a new approach to digital waterm arking is presented and a range of possible applications are considered. The process is defined by using concepts and techniques borrowed from Cryptography. It is based on com puting a 'scram ble im age' by diffusing a waterm ark im age with a noise field (a cipher). The cover im age (covertext) is then introduced using a sim ple additive process (confusion). The waterm ark is subsequently recovered by rem oving the covertext and then correlating the output with the original (key dependent) noise field. For covert encryption, this approach provides the user with a m ethod of hiding ciphertext (the scram bled im age) in a host im age before the transm ission of t he data. With regard to dcum ent authentication, a diffusion only or ' texture coding' approach that is

Locally optimum detection for Barni's multiplicative watermarking in DWT domain

With the increasing demands of copyright protection, watermarking technology has being paid more and more attention. In the design of a watermarking algorithm, a good watermark detection scheme can improve the detection rate, which pushes an increasing number of researchers to work with optimum detectors. In this paper, we propose a locally optimum using a locally most powerful test with respect to Barni's multiplicative water marking which is based on the human visual system (HVS). In the proposed detection scheme, the probability density function of DWT coefficients is modeled using the generalized Gaussian distribution, and the decision threshold is obtained by the Neyman–Pearson (NP) criterion. Additionally, we prove that the existing correlation detection is a special case of the proposed locally optimum detection, and we provide an improved correlation threshold under the condition of locally optimum detection.

Multimedia Digital Rights Protection Using Watermarking Techniques

ABSTRACTWith the advancement of Internet technologies and its wide usage, it has become easy to illegally copy, distribute, and manipulate digital products. Digital watermarking is a proven method to protect authenticity by identifying the owner of the digital content. Significant work has been reported in the last five years on legal and technical measures for protecting digital rights. This paper explains the concepts of ownership rights and related intellectual property rights and their technical and legal protection measures. It also introduces digital water marking, its classification, features, and applications.

Comments on "Why watermarking is nonsense"

Comments on "Why watermarking is nonsense"

ElGarnal함수를 사용하는 디지털 이미지 워터마킹 기법

디지털 이미지 워터마킹(digital image watermarking)은 이미지 소유자의 정보를 디지털 이미지 속에 삽입시켜 이미지 소유자의 저작권을 보호하는 것을 목적으로 하는 기법이다. 저작권 보호를 위한 디지털 이미지 워터마킹 기법은 기존의 스테가노그라피(steganography)보다 워터마킹 공격에 대한 견고성과 육안적 비구별성을 동시에 추구해야 하고, 워터마킹 알고리즘의 은닉성 대신 키의 은닉성이 보장되어야 하며, 암호학과 마찬가지로 키의 사용으로 허가받지 않은 사용자의 워터마크 검출을 방지할 수 있어야 한다. 본 논문에서는 암호학 함수인 ElGamal함수를 사용하는 워터마킹 기법을 제안한다. 일방향 해쉬 함수를 구현하기 위해 ElGamal일방향 함수와 모듈라 연산을 사용한다. 제안하는 워터마킹 기법은 LSB(least significant bit)공격과 감마 보정 공격에 대해 견고하며 육안적 비구별성(perceptual invisibility)이 높다. 제안하는 워터마킹 기법의 실제 구현 및 실험을 통한 실험 결과를 분석하여 견고성과 육안적 비구별성의 특징을 확인한다 향후 과제로, 키생성을 위한 의사난수성과 비대칭키의 생성을 동시에 달성시키는 알고리즘 연구가 요구된다. Digital image watermarking is a technique for the purpose of protecting the ownership of the image by embedding proprietary watermarks in a digital image. It is required for the digital image watermarking scheme to pursue the robustness against water marking attacks and the perceptual Invisibility more than usual in steganography area, to guarantee not a hidden watermarking algorithm but the publicity of water-marking algorithm details and hidden use of key, which can protect the unauthorized user access from detection. In this paper we propose a new copyright watermarking scheme, which is barred on one-way hash functions using ElGamal functions and modular operations. ElGamal functions are widely used in cryptographic systems. Our watermarking scheme is robust against LSB(least significant bit) attacks and gamma correction attack, and also perceptually invisible. We demonstrate the characteristics of our proposed watermarking scheme through experiments. It is necessary to proceed as the future work the algorithm of achieving at the same time both the pseudo-randomness for the steno-key generation and the asymmetric-key generation.

Research on Fragile Water marking Problems

Research on Fragile Water marking Problems

An investigation into water marking and colour change in tussah silk fabric during moisture absorption

This study investigates the phenomena of water marking and colour change in tussah silk fabric. Fully wetting the fabric and applying a small amount of moisture (by steaming) both result in changes in the fabric's optical properties: fully wetting causes a decrease in the reflectance of the fibre surface, while exposure to small amounts of moisture results in an increase. Lustre changes (reflectance variations) of tussah fabrics after wet or steam treatments are macroscopic effects of changes in the optical reflectance of the fibres and indicate that the visual colour differences in the fabric following water marking or colour change result from structural changes in the fibres.

Adaptive water marking

The watermark is an important protection and identification technique that allows an invisible mark to be placed on top of normal information such as bank note, ID card, magnetic card and valuable documents. Watermarking techniques have been developed to protect digital images against illegal reproduction and illegal modifications when visibility to users is required. Here, we present a new adaptive watermarking algorithm. The adaptive watermark is generated from the image content and can be treated as a digital fingerprint of the image. As a transform based algorithm is used to encode the information in the histogram domain the proposed watermark is robust enough against any degradation, hacking and attack.

Watermarking by numbers

Watermarking by numbers

Chemical Watermarking of Paper

Chemical Watermarking of Paper