Watermark Insertion Research Articles

Particle Swarm Optimization and Discrete Wavelet Transform based Robust Image Watermarking

Objectives: Watermarking technique on digital images with improved robustness and with optimum results can be achieved by using the intelligent technique Particle Swarm Optimization (PSO). Discrete Wavelet Transform (DWT) is used to uncover perceptually significant coefficients from the digital image. Methods: PSO is one amongst the efficient techniques in optimizing a problem having many numbers of candidates. This robust technique consists of two stages namely embedding and extraction stages. Insertion of watermark into the image is done at the embedding stage. Before embedding watermark into the image perform DWT and select any one of the bands LL, LH, HL and HH. Initially select the coefficients randomly and the optimal DWT coefficients for embedding the watermark at various positions are identified by PSO. Findings: In watermark extraction stage, the embedded watermark is identified by doing the reverse process. Robustness of the digital image watermarks implies the strength of the watermark against various image processing attacks and this can be checked by evaluating Cross Correlation value that is Normalized (NCC) and for fidelity Peak Signal to Noise Ratio (PSNR). It is evident that the robustness of the image is well maintained by this technique. As a further improvement any of the other intelligent technique namely Ant Colony Optimization can be used for optimization evaluation. Applications: Digital image watermarking plays a vital role in copyright infringement issues and it helps in predicting the authorized user by the digital signature that is watermarked in the image.

Quality assured and optimized image watermarking using artificial bee colony

Watermarking is a process of secret information (watermark) insertion in the digital image, which later on helps in finding out the correct owner of that image. The insertion of watermark’s singular values into the host image provide a high value of capacity, robustness and imperceptibility but the scheme remain vulnerable towards false positive attacks. Alternatively, insertion of watermark’s principle components into the host image make the scheme secured towards security errors but it also reduces the robustness and imperceptibility of the scheme. The exact recovery of this information becomes even more difficult after attacks because attacks change the information even further. This eventually leads to low imperceptibility and robustness of scheme. In general, the optimization of embedding strengths for image watermarking focuses on the maximization of both imperceptibility and robustness equally. In doing so, often, imperceptibility suffers as it gets degraded beyond a certain limit (<35 dB). This degradation becomes unacceptable in many fields because important information of host image might get lost. In this study, the optimization is performed with a quality assurance so that imperceptibility of scheme does not fall below a user specific threshold. The proposed scheme shows a very decent performance after optimization.

Multipurpose image watermarking in the domain of DWT based on SVD and ABC

A multipurpose image watermarking scheme is proposed in the present work in order to provide tamper localization, self-recovery and ownership verification of the host image. For robust watermarking, gray scale watermark is utilized to provide generalization and wide applicability to proposed scheme. The host is first transformed into the wavelet domain using DWT (Discrete Wavelet Transform) and then singular values of transformed host are modified in accordance with the principal components of watermark. This insertion make the scheme free from false positive error as well as it provides a decent capacity too. After the insertion of robust watermark, the last two LSB (Least Significant Bit) of host are modified in such a way that it contains the scrambled and deterministic average representation of host itself along with the SVD (Singular Value Decomposition) based tamper localization information. The LSB insertion is used to locate the tampered region as well as to provide the self-recovery feature to the scheme. The robust insertion is also optimized with the help of ABC (Artificial Bee colony) in such a way that maximum robustness can be assured corresponding to user specific threshold of imperceptibility.

Low-Complexity Watermarking into SAO Offsets for HEVC Videos

This paper proposes a new watermarking algorithm to embed watermarks in thr process of sample adaptive offsets (SAO) for high efficiency video coding (HEVC) compressed videos. The proposed method embeds two-bit watermark into the SAO offsets for each coding tree unit (CTU). To minimize visual quality degradation caused by embedding watermark, watermark bits are embedded into SAO offset depending on the SAO types of block. Furthermore, the embedded watermark can be extracted by simply adding four offsets and checking their least significant bits (LSB) at the decoder side. The experimental results show that the proposed method achieves 0.3% BD-rate increase without much visual quality degradation. Two-bit watermark for each CTU is embedded for more bit watermarking. In addition, the proposed method requires negligible computational load for watermark insertion and extraction.

Sliding window used for Robustness Optimization Employing Neighborhood concept and Genetic Algorithm

Fast distribution of digital contents through open networks is not posing a significant problem due to digital media revolution. Modern technologies have also reduced the reproduction time of digital media and its fast distribution. However, this facility has also the darker side where unauthorized users can tamper its contents and manipulate the digital data thus giving rise to serious security concerns. This problem has to be addressed very seriously. Digital watermarking techniques have recently evolved to address the above problems. The usage of these digital watermarks prevent illegal reproduction and usage of digital data as well as help in identifying the origin, author, owner etc even after various manipulations or attack on the digital data. A number of watermarking techniques in spatial and frequency domain were given by various researchers which suffered from problems robustness. Genetic algorithm provides an alternative way of creating watermarks with Promising values of robustness aspect of watermarking. This paper deals with design and development of a new watermarking technique which uses genetic algorithm to identify locations within the cover image for watermark insertion in spatial domain and then apply the average neighborhood concept for the purpose of watermark insertion and extraction ensuring higher robustness and resilience to several possible image attacks. Genetic search often produces same watermark locations in different populations for watermark insertion resulting in poor value of robustness, which need to be checked. Sliding window concept introduced in this paper uses a set of a few genes which are serially shuffled to get new set of locations for watermarking during each population generation and helps in enhancing robustness aspect of watermarking. Roulette-wheel selection has been used while using the genetic algorithms developed in the paper.

Exploring Low Cost Optimal Watermark for Reusable IP Cores During High Level Synthesis

The challenges in the current design process for consumer electronics products include greater complexity and stiff time-to-market pressure, which has led to the usage of reusable intellectual property (IP) cores (such as JPEG and MPEG) as a sustainable solution. This has led to the domain of IP protection for anti-piracy as an important subject of research for a system design. Watermarking is expected to provide the best protection of authorship when applied at higher levels, i.e., during high-level synthesis. It is also well acknowledged that watermark insertion is non-trivial, as it is very difficult to choose a strong signature that results in higher security and less area overhead among available design solutions. This paper presents a novel multi-variable signature encoding for embedding a dynamic watermark in an IP design during architectural synthesis that provides enhanced security against typical attacks. Owing to the involvement of multiple (four) variables in the proposed signature, it is difficult to realize the signature without complete encoding knowledge of the four variables. Second, our approach aims to optimize the embedding cost of the watermark by exploring a low-cost solution through particle swarm optimization-driven design space exploration based on area-delay constraints. Comparison with a recent technique indicated that our watermark incurs lower embedding cost, lower runtime, and less storage hardware.

해상도에 따른 DWT 기반 디지털 영상의 강인성 블라인드 워터마킹

This paper proposes a blind watermarking scheme using DWT satisfying robustness, invisibility, and security to protect the ownership of digital image contents. This scheme does not determine any watermarking position by local image information. It rather inserts the watermark information into all the four lowest frequency subbands after transforming the host image by n-level 2-dimensional DWT, depending on, the sizes of the host image and the watermark data. Its watermark insertion methodology uses some weighting factors according to the kind of the subband and its energy level to adjust the invisibility and the robustness of the watermark. This method is experimented for various pixel-value change attacks and geometric attacks with various images having different resolutions and aspect ratios. With the experimental results and by comparing with existing methods, we show that the proposed method has a great deal of general usage with good watermark invisibility and good robustness against attacks.

Robust watermarking scheme and tamper detection based on threshold versus intensity

Abstract A watermarking field is necessary to prove the copyright, ownership, authenticity and other related security aspects of the electronic data. Semi-Blind watermarking refers to need the watermark image during the extraction process. While, informed watermarking generates the watermark data from the original image itself. Moreover, Tamper detection is useful to discover the tamper zone in the image. In this paper, we propose a semi blind and informed watermarking approach. We build the watermark from the original image using Weber Law. Our approach aims to provide a high robustness and imperceptibility with perfectly tamper detection zone. We divide the original image into blocks and the main pixel is chosen for watermark insertion, where the embedding/extraction operates in the spatial domain. The tamper detection is tested by tampering watermarked image, and then based on the extracted attacked watermark; we can discover the tamper area. Also, the robustness watermarking aspect is proved against different kind of geometric and non-geometric attacks. Based on the experimental results, the imperceptibility and robustness of our watermarking approach are proven and showing perfectly the detection of the tamper zones.

Adaptive Watermarking based on Tree Structure based using 3-4 Level DWT and DCT

An adaptive watermarking scheme provides more contribution related to DWT for image content. In this paper an adaptive watermarkingschemeusing tree structure is proposed.This watermarking method makes use of a classificationprocedure for identifying various parts of the image which can be watermarkedby using the most suited modulation DWT. This classificationdependson a reference image which is derived from the image itself and aprediction of it necessarywhich has the property of being invariant change tothe watermark insertion process.In this paper the results on the basis of psnr, mse, entropy and embedding capability, mean ssim, just noticeable difference have been found. This algorithm is better for the psnr and embedding capability as compared to the previous algorithm. Proposed algorithm has improved successful watermarking image for future work with other compatible algorithm for the security purpose.

Blind Watermarking Scheme based on U matrix Through QSVD Transformation

In this paper, a novel blind color image watermarking technique using U matrix through QSVD transformation is proposed to protect the intellectual property rights of color images. The proposed method tries to insert the watermark through moderating the coefficient of the quaternion elements in U matrix. .In this method, the color image is considered as an array of pure quaternion numbers. Then the array of pure quaternion is divided into non-overlapping blocks and we perform QSVD to the block to get the U matrix. The watermarking is inserted into the coefficient of the quaternion elements in the first column of the U matrix. Besides, in the procedure of watermark insertion and extraction, ensuring higher fidelity and robustness and resilience to several possible image attacks have been considered. The experimental results showed that the proposed method performance created watermarked images with better PSNRs and more robustness versus several attacks such as Salt &Pepper noise, Brightness adjustment, Sharpen and Blurring and Clipping.

Information Hiding Method Using Best DCT and Wavelet Coefficients and Its Watermark Competition

In recent years, information hiding and its evaluation criteria have been developed by the IHC (Information Hiding and its Criteria) Committee of Japan. This committee was established in 2011 with the aim of establishing standard evaluation criteria for robust watermarks. In this study, we developed an information hiding method that satisfies the IHC evaluation criteria. The proposed method uses the difference of the frequency coefficients derived from a discrete cosine transform or a discrete wavelet transform. The algorithm employs a statistical analysis to find the best positions in the frequency domains for watermark insertion. In particular, we use the BCH (Bose-Chaudhuri-Hocquenghem) (511,31,109) code to error correct the watermark bits and the BCH (63,16,11) code as the sync signal to withstand JPEG (Joint Photographic Experts Group) compression and cropping attacks. Our experimental results showed that there were no errors in 10 HDTV-size areas after the second decompression. It should be noted that after the second compression, the file size should be less than 1 25 of the original size to satisfy the IHC evaluation criteria.

An Efficient and Impartial Buyer-Seller Watermarking Protocol

 Buyer-seller watermarking protocols are designed to deter clients from illegally distributing copies of digital content. To be efficient and fair is important to buyer-seller protocols. In this paper, an anonymous and interactive buyer-seller protocol is proposed, which is designed to be impartial and efficient. To solve the unbinding problem and the buyers’ right problem, operations of watermark insertion and digital content selling are performed by a Trusted Third Party in the proposed scheme. Buyers and sellers have equal rights and responsibilities, and computational and corresponding overhead is reduced. We show that the proposed protocol is fair, secure and efficient.

IJARCCE - Computer and Communication Engineering

Digital watermarking is now an established & cost effective method for data authentication and for protection of multimedia data. Many standard and commercially available software are available for this purpose. In this paper an attempt has been made to modify the method of Reddy and Chatterji [13, 14] by using contourlet transform for the watermark signal. The theoretical background of the method along with the simple development of the contourlet transform has been given. The algorithms for watermark insertion and detection are provided. The method was used for many different types of images and watermarks. A set of five such results are given along with the PSNR (peak signal to noise ratio) values of watermarked images and the detected watermarks.

Robust watermarking against print and scan attack through efficient modeling algorithm

This article proposes a blind discrete wavelet transform-discrete cosine transform (DWT-DCT) composite watermarking scheme that is robust against print and scan distortions. First, two-dimensional DWT is applied to the original image to obtain the mid-frequency subbands. Then, a one-dimensional DCT is applied to the selected mid-frequency subbands to extract the final coefficients for embedding the watermark. To specify watermarking parameters, we utilize a Genetic Algorithm to achieve a predefined image quality after watermark insertion. Suitable locations for watermarking are determined by analyzing the effect of a modeling algorithm. This model simulates noise and nonlinear attacks in printers and scanners through noise estimation and system identification methods. The experimental results demonstrate that the proposed algorithm has a high robustness against print and scan attack such that its robustness is higher than related watermarking algorithms.

Robust digital watermarking based on local invariant radial harmonic fourier moments

It is a challenging work to design a robust image watermarking scheme against local geometric distortions. Radial harmonic Fourier moments (RHFMs) is a powerful tool in image processing owing to its better image description capability, lower noise sensitivity, and geometric invariance property. Based on SURF (Speeded-up robust features) detector and invariant RHFMs, we proposed a robust image watermarking scheme against local geometric distortions in this paper. Firstly, the SURF detector, which is a fast and highly performant multiscale feature detector, is used to extract image feature points in original image. Secondly, the stable and non-overlapped local circular regions centered at feature points are thereafter constructed and selected by combining characteristic scales and feature points refinement. And finally, the digital watermark is embedded in the invariant RHFMs of the local circular regions. Similarly to watermark insertion, the digital watermark can be blindly detected from the local circular regions. Experimental results confirm the validity of our approach and its higher robustness against various attacks (especially local geometric distortions) compared to alternative watermarking methods in the literature.

English

Telemedicine is well known application where enormous amount of medical data need to be transferred securely over network and manipulate effectively. Security of digital data, especially medical images, becomes important for many reasons such as confidentiality, authentication and integrity. Digital watermarking has emerged as a advanced technology to enhance the security of digital images. The insertion of watermark in medical images can authenticate it and guarantee its integrity. The watermark must be generally hidden does not affect the quality of the medical image. In this paper, we propose blind watermarking based on Discrete Wavelet Transform (DWT), Discrete Cosine Transform (DCT) and Singular Value Decomposition (SVD), we compare the performance of this technique with watermarking based DWT and SVD. The proposed method DWT, DCT and SVD comparatively better than DWT and SVD method.

Digital Image Watermarking With Random Selection of Watermark Insertion Having Adaptive Strength

We have presented an algorithm of digital image watermarking for gray scale images which we implemented in frequency domain. Before inserting the watermark, we added the Hamming codes row wise as well column wise. Two encryption techniques were implemented on the ECC inserted watermark for its security. The pixel position for inserting the watermark was calculated using starting row and column number for that 8×8 block. Pixel embedding strength is calculated using criteria that low frequency is robust in general signal processing attacks, thus choosing less value to be embedded and vice-versa. Results show that the watermarking algorithm is robust against common signal processing attacks. The algorithm is tested against multiple attacks also.

Minimisation of image watermarking side effects through subjective optimisation

This study investigates the use of structural similarity index (SSIM) on the minimised side effect to image watermarking. For the fast implementation and more compatibility with the standard discrete cosine transform (DCT)-based codecs, watermark insertion is carried out on the DCT coefficients and hence an SSIM model for DCT-based watermarking is developed. For faster implementation, the SSIM index is maximised over independent 4 × 4 non-overlapped blocks, but the disparity between the adjacent blocks reduces the overall image quality. This problem is resolved through optimisation of overlapped blocks, but, the higher image quality is achieved at a cost of high computational complexity. To reduce the computational complexity while preserving the good quality, optimisation of semi-overlapped blocks is introduced. The authors show that while SSIM-based optimisation over overlapped blocks has as high as 64 times the complexity of the 4 × 4 non-overlapped method, with semi-overlapped optimisation the high quality of overlapped method is preserved only at a cost of less than 8 times the non-overlapped method.

A geometrical attack resistant image watermarking algorithm based on histogram modification

In order to avoid geometric distortions in watermark embedding, a geometrical attack resistant image watermarking algorithm is proposed based on histogram modification. The watermark information is embedded into the host image by modifying the number of the gray samples of the image histogram. In a fixed gray range, every three consecutive bins are divided into a group for embedding one-bit watermark, through modifying the sample value of a bin to another of the adjacent bin to realize the watermark insertion. Moreover, to avoid duplicate modification and improve the transparency, only one bin is modified every two neighbor bins, the modified histogram is mapped into the watermarked image. For watermark detection, it is in fact an inverse process of watermark embedding. Watermark is extracted through calculating and judging the relationship of the number of samples of the three successive bins. The experimental results show that the algorithm is robust to both geometrical attacks and those conventional signal processing attacks.

A robust color image watermarking technique using modified Imperialist Competitive Algorithm

In this paper, a novel robust watermarking technique using Imperialistic Competition Algorithm (ICA) in the spatial domain is proposed to protect the intellectual property rights of color images. The proposed method tries to insert the watermark in the blocks which are selected by Modified ICA. In this method, ICA has been customized for watermarking. The color band for watermark insertion is selected based on color dynamic range in each block. Besides, in the procedure of selecting blocks for watermark insertion and extraction, ensuring higher fidelity and robustness and resilience to several possible image attacks have been considered. The experimental results showed that the proposed method performance created watermarked images with better PSNRs and more robustness versus several attacks such as additive noise and blurring in compare to related works.