Copyright Protection Of Digital Images Research Articles

A Hybrid Domain Color Image Watermarking Based on DWT–SVD

In recent years, digital image watermarking has been emerged as a promising solution for copyright protection and authentication problem of digital images. Among several existing watermarking schemes, very few have been designed for the authenticity and copyright protection problem of color images. To protect the copyright and validate the authenticity of color images, in this paper a hybrid robust image watermarking scheme based on discrete wavelet transform (DWT) and singular value decomposition is proposed and simulated. Initially, RGB color image is switched to YCbCr color space from which only Y achromatic component is considered for watermark data insertion. In the next step, Y component of the YCbCr color model is decomposed into non-overlapping blocks and subsequently DWT are applied to each block. In this work, non-overlapping decomposed gray watermark image blocks are embedded into singular values of DWT-transformed cover image blocks. Proposed technique’s simulation result established the robustness by extracting adequate watermark data from the restructured cover image after applying common geometric transformation attacks (like rotation, flip operation, cropping, scaling, shearing and deletion of lines or column operation), common enhancement technique attacks (like lowpass filtering, histogram equalization, sharpening, gamma correction, noise addition), JPEG compression attacks and combinational attacks (like combination of geometric transformation attacks and common enhancement technique attacks, combination of geometric transformation attacks and JPEG compression attacks, combination of common enhancement technique attacks and JPEG compression attacks, and combination of geometric transformation attacks and geometric transformation attacks).

Digital image ownership authentication via camouflaged unseen-visible watermarking

In recent years, end users can easily capture digital images using several devices, such as smartphones, mobile devices and digital imaging cameras, allowing such images to be easily copied, manipulated, transmitted or format converted without any restrictions. This fact suggests the necessity to develop digital tools, such as digital watermarking, to solve the issues associated with copyright protection and ownership authentication of digital images. To claim the ownership of a digital image, we propose a camouflaged, unseen-visible watermarking technique based on luminance and texture properties in conjunction with an image enhancement criterion. The proposed method has some advantages over invisible and visible watermarking methodologies in terms of readability and imperceptibility of the watermark, respectively. The experimental results demonstrate that the proposed scheme is effective and applicable for digital images on a variety of topics, including natural scenes and man-made objects, both indoors and outdoors. A comparison with previously reported methods based on unseen-visible watermarking techniques is also provided.

Hybrid blind robust image watermarking technique based on DFT-DCT and Arnold transform

In this paper, a robust blind image watermarking method is proposed for copyright protection of digital images. This hybrid method relies on combining two well-known transforms that are the discrete Fourier transform (DFT) and the discrete cosine transform (DCT). The motivation behind this combination is to enhance the imperceptibility and the robustness. The imperceptibility requirement is achieved by using magnitudes of DFT coefficients while the robustness improvement is ensured by applying DCT to the DFT coefficients magnitude. The watermark is embedded by modifying the coefficients of the middle band of the DCT using a secret key. The security of the proposed method is enhanced by applying Arnold transform (AT) to the watermark before embedding. Experiments were conducted on natural and textured images. Results show that, compared with state-of-the-art methods, the proposed method is robust to a wide range of attacks while preserving high imperceptibility.

Histogram shifting-based blind watermarking scheme for copyright protection in 5G

In this article, we propose a novel robust and blind image watermarking scheme based on speeded up robust feature points for copyright protection of digital images in the fifth generation (5G) wireless communication. Encryption techniques have been already incorporated in the current wireless communication technologies. Similarly, copyright protection through watermarking can also be incorporated in future 5G wireless communication. The novelty of the proposed image watermarking scheme is that a new histogram shifting procedure has been introduced on the non-overlapping circular regions around the selected stable keypoints on the image. A new similarity measure based on longest common subsequence is also introduced to find the closeness between two watermark bit sequences even when they have different sizes. The proposed method outperforms the existing competing methods on standard image database (University of Southern California-Signal and Image Processing Institute) in terms of robustness, visual quality, and data embedding rate.

A Study on the Copyright Protection and Improvement of Digital Image

A Study on the Copyright Protection and Improvement of Digital Image

A Robust Image Watermarking Scheme Based on SVD in the Spatial Domain

With the development of image processing technology, the copyright protection of digital images has become an urgent problem to be solved. As an effective method, the robust digital watermarking technique emerges at a historic moment. Currently, most robust watermarking schemes are performed in the transform domains, such as the discrete cosine transform (DCT) and singular value decomposition (SVD). Compared with spatial domain watermarking schemes, these methods have achieved good performance, such as better robustness and higher security. However, the computational complexity increases with the use of forward and reverse transforms. In this paper, we analyze the SVD-based watermarking scheme and its impact on the spatial domain. Based on this analysis and the mathematical characteristics of SVD, we present a robust image watermarking scheme where a binary watermark is embedded into the largest singular value of each image block in the spatial domain. Several experiments are conducted to verify the performance of the proposed watermarking scheme. The experimental results show that compared with the existing SVD domain watermarking schemes, our proposed method has maintained good robustness against various attacks. Moreover, it avoids the false positive problem existing in traditional SVD-based watermarking schemes and has lower computational complexity.

New Copyright Protection Scheme for Digital Images Based on Visual Cryptography

ABSTRACTThe paper proposes a robust and blind watermarking scheme based on visual cryptography for copyright protection of digital images. It shuffles the pixel locations of the binary watermark using Arnold cat map transform to realize the effect of encryption for better security and it divides the image into blocks of equal size. Two secret shares are generated from the watermark and the image based on visual cryptography by comparing the global mean value of the pixels in the image with the mean values of all pixels of randomly selected blocks. As documented in the experimental results, the proposed scheme is more robust in comparison with other visual cryptography-based watermarking schemes. It can resist several attacks such as JPEG compression, gamma correction, impulse noise, Gaussian noise, blurring, median filter, rotation, scaling, and sharpening attacks on different types of images. The computational time for generating secret shares and detection of the watermark is comparatively small.

An Approach for Image Copyright Protection by using Walsh Hadamard Method

Protecting copyrighted image from abuse, misuse and piracy is being critical day by day. Digital image Copyright Protection is considered as a solution to prevent the piracy of original image data. In this article, the authors propose copyright protection method using the well-known Walsh Hadamard transformation along with discrete wavelet transformation and singular value decomposition to achieve robust and imperceptible copyrighted image. The optimum scaling factor which decides the strength of signature image to be embedded is obtained at 0.3. The proposed article ensures imperceptibility of copyrighted image which is determined by Peak signal to noise ratio value greater than 35dB. Normalized Correlation value nearly equals to 0.9999 provides robustness against different attacks such as image cropping, rotations and noise on copyrighted image. Journal of the Institute of Engineering, 2016, 12(1): 162-168

A copyright protection scheme for digital images based on shuffled singular value decomposition and visual cryptography.

This paper proposes a new watermarking algorithm based on the shuffled singular value decomposition and the visual cryptography for copyright protection of digital images. It generates the ownership and identification shares of the image based on visual cryptography. It decomposes the image into low and high frequency sub-bands. The low frequency sub-band is further divided into blocks of same size after shuffling it and then the singular value decomposition is applied to each randomly selected block. Shares are generated by comparing one of the elements in the first column of the left orthogonal matrix with its corresponding element in the right orthogonal matrix of the singular value decomposition of the block of the low frequency sub-band. The experimental results show that the proposed scheme clearly verifies the copyright of the digital images, and is robust to withstand several image processing attacks. Comparison with the other related visual cryptography-based algorithms reveals that the proposed method gives better performance. The proposed method is especially resilient against the rotation attack.

A New Robust Blind Copyright Protection Scheme Based on Visual Cryptography and Steerable Pyramid

In this paper, we proposed a novel blind digital image copyright protection scheme based on Steerable pyramid transform (SPT) and visual cryptography (VC). Unlike traditional watermarking schemes, the proposed method does not alter the original image by embedding the watermark image. Steerable pyramid transform is performed on the original image, and the low sub-band is selected. The watermark image is divided into two random looking images, called private and public shares using the visual secret sharing scheme and the selected low sub-band features. To reveal the watermark image, the two shares are stacked together while using each share separately reveals no information about the watermark image. A series of attacking experiments are performed on the original image to test the robustness of the proposed method. The experimental results show excellent visual imperceptibility and robustness against a variety of attacks.

Copyright Protection for Digital Colour Images Using Dual Watermarking Technique by Applying Improved DWT, DCT and SVD

The main objective of the majority of research in Digital Image Watermarking technique is to improve the robustness of attacks.In this paper, a new algorithm has been proposed based on Discrete Wavelet Transform, Discrete Cosine Transformation in association with Singular Value Decomposition for embedding the dual watermark which provides an efficient copyright protection.Here the primary watermark is embedded into the secondary watermark and the resultant image is used as a watermark for the host or cover image. The primary and secondary watermarks are retrieved back by using an efficient watermark retrieving algorithm. During the processes of embedding the scaling factor is varied to improve the quality of watermarked image. In this proposed algorithm the watermarked image is extracted back with same quality, high peak signal to noise ratio and normalized correlation coefficients. The quality of the extracted watermarks is authenticated using Peak Signal to Noise Ratio and Normalized Correlation Coefficient. Compared with previous methods the proposed algorithm has a significantly higher robustness against various geometrical and removal attacks.Nearly 28 attacks like Cropping, Rotating at various angles, Sharpening, Motion Blur, rescaling, resizing and adding noise like Salt and Pepper noise, Gaussian noise, Spackle noise, filters like average filter, median filters are attempted. Even after attempted all such attacks both the watermarks are retrieved back with the same quality and high normalized correlation coefficient.

Dual plane multiple spatial watermarking with self-encryption

Watermarking has established itself as a promising solution in the context of digital image copyright protection. Frequency domain watermarking is mainly preferred due to associated robustness and perceptual issues but requires a large amount of computation. On the other hand spatial domain watermarking is much faster but lacks when robustness is concerned. In this paper a block based spatial domain watermarking technique for color images is proposed that is fast and robust. Two-way embedding introduced in the paper provides capability to previously estimate perceptual degradation in host image due to watermark embedding. Multiple watermarking in two component images is used to achieve better imperceptibility and better robustness. Self-encryption introduced aims to remove dependency over external secret key however optional encryption with random secret keys is proposed for providing better security. Proposed embedding technique is an effort to achieve proper balance between robustness and quality degradation of image. Experiments suggest proposed method is robust against processing attacks such as spatial filtering transformations image enhancement and loss compression.

PDE based scheme for multi-modal medical image watermarking.

BackgroundThis work deals with copyright protection of digital images, an issue that needs protection of intellectual property rights. It is an important issue with a large number of medical images interchanged on the Internet every day. So, it is a challenging task to ensure the integrity of received images as well as authenticity. Digital watermarking techniques have been proposed as valid solution for this problem.MethodsIt is worth mentioning that the Region Of Interest (ROI)/Region Of Non Interest (RONI) selection can be seen as a significant limitation from which suffers most of ROI/RONI based watermarking schemes and that in turn affects and limit their applicability in an effective way. Generally, the ROI/RONI is defined by a radiologist or a computer-aided selection tool. And thus, this will not be efficient for an institute or health care system, where one has to process a large number of images. Therefore, developing an automatic ROI/RONI selection is a challenge task. The major aim of this work is to develop an automatic selection algorithm of embedding region based on the so called Partial Differential Equation (PDE) method. Thus avoiding ROI/RONI selection problems including: (1) computational overhead, (2) time consuming, and (3) modality dependent selection.ResultsThe algorithm is evaluated in terms of imperceptibility, robustness, tamper localization and recovery using MRI, Ultrasound, CT and X-ray grey scale medical images. From experimental results that we have conducted on a database of 100 medical images of four modalities, it can be inferred that our method can achieve high imperceptibility, while showing good robustness against attacks. Furthermore, the experiment results confirm the effectiveness of the proposed algorithm in detecting and recovering the various types of tampering. The highest PSNR value reached over the 100 images is 94,746 dB, while the lowest PSNR value is 60,1272 dB, which demonstrates the higher imperceptibility nature of the proposed method. Moreover, the Normalized Correlation (NC) between the original watermark and the corresponding extracted watermark for 100 images is computed. We get a NC value greater than or equal to 0.998. This indicates that the extracted watermark is very similar to the original watermark for all modalities.ConclusionThe key features of our proposed method are to (1) increase the robustness of the watermark against attacks; (2) provide more transparency to the embedded watermark. (3) provide more authenticity and integrity protection of the content of medical images. (4) provide minimum ROI/RONI selection complexity.

A Semi-Blind Robust DCT Watermarking Approach for Sensitive Text Images

This paper presents a new approach to address the challenges associated with integrity verification, proof of authenticity, tamper detection and assurance of copyright protection for digital images propagated online. In particular, the problem addressed here primarily relates to the protection of sensitive online textual images that may be targeted for counterfeiting or intentional/unintentional modifications which would result with a fake copy being disseminated. Typically, sensitive text images are characteristic of further challenges and constraints on embedding/extraction techniques compared to their more general digital picture/image counterparts. With many digital protection schemes addressing the problem of less-sensitive content comprising of a rich set of colours and textures, this paper proposes a novel watermarking approach for the case of sensitive text images in order to confirm content originality and integrity verification under some known constraints of the image type. Hence, a new approach based on discrete cosine transform and linear interpolation is proposed and applied on digital Quran text images, which are considered as ideal samples of content with stringent sensitivity requirements. Detailed results had presented the significance of this approach and had demonstrated the high robustness obtained when faced with various attack scenarios that include rotational attacks, JPEG compression attacks, noising attacks and median filtering attacks. Significantly, a major contribution of this paper was found in the novel watermark extraction approach which had enabled perfect watermark extraction under a range of attack scenarios. Finally, a significant advantage of the proposed approach was found in its broad applicability for authentication and protection of other sensitive and less-sensitive digital image content.

A watermarking scheme for digital images based on visual cryptography

A robust and blind watermarking scheme based on visual cryptography for copyright protection of digital images is proposed in this paper. It generates two shares of the secret image based on visual cryptography by comparing the pixel value of the image with the mean of the pixel values in each image block. The experimental results show that the proposed scheme clearly verifies the copyright of the digital images and is more robust in comparison with other visual cryptography based watermarking methods on a variety of attacks.

Adaptive Digital Watermarking for Copyright Protection of Digital Images in Wavelet Domain

Abstract Digital image watermarking is the process of embedding watermark into a digital image for authentication and thereby protecting the digital image from copyright violation. In this paper, an adaptive invisible watermarking scheme is proposed in wavelet domain. The proposed method is adaptive in the sense that the scaling and embedding factors are calculated using Bhattacharyya distance and the fourth cumulant moment - kurtosis. The proposed method can be easily employed to preserve the ownership rights and in addition for piracy of digital data prevention. The proposed method is robust to all image and signal processing attacks and highly secured for the protection of copyright information as the process is executed in wavelet domain. Experimental results and statistical evaluation of the results shows the efficacy of the proposed method.

Effect of Weight Factor on The Performance of Hybrid Column Wavelet Transform used for Watermarking under Various Attacks.

Digital image watermarking is aimed at copyright protection of digital images. Strength of embedded watermark plays an important role in robustness and invisibility of watermarking technique. In this paper, effect of two parameters namely, watermark strength and middle frequency coefficients of host image used for embedding watermark is studied. In the given watermarking technique, watermark is normalized before embedding. This reduces the strength of watermark so that there will be minimum possible distortion in watermarked image. However, it has been observed in our work proposed in previous paper that, such embedment responds poorly to various image processing attacks like compression, cropping, resizing, noise addition etc. Hence in this paper, an attempt has been made to increase the strength of embedded watermark by using suitable weight factor so that robustness of watermarking technique proposed in our previous paper is further increased with small acceptable decrease in imperceptibility. Also middle frequency elements of host image selected for embedding watermark are varied by selecting different rows of host such that slowly we move from middle frequency components towards high frequency components. For certain attacks like image cropping, selection of middle frequency coefficients affects the robustness achieved. Increase in weight factor significantly improves the performance of given watermarking technique by more than 50% as proposed in our previous paper where weight factor value was 25.

A Robustness Watermarking Achievement Algorithm with Block Compressed Sensing Theory

In order to take into account the tradeoff relation between the watermark quality and the watermark robustness in digital image copyright protection, a novel generation method of image watermarking is proposed with block compressed sensing in DWT domain. The watermark data are formed by utilizing measurement values of blocking compressed sensing to fingerprint image, and are embedded into all sub-blocks of the LLn sub-band of the transformed host image. Experimental results show that the introduction of compressed sensing theory improves the robustness for resisting attacks and recovery quality of the fingerprint image watermarking.

A Fingerprint-Based Digital Images Watermarking for Identity Authentication

In this paper the combination of fingerprint verification methods with watermarkingtechnology to provide copyright protection and authentication of digital images is proposed. The goalof this study is to investigate how watermarking processing affects the quality of biometric watermarks.Performed experiments showed that extracted fingerprint images have roughly equal verification performance even if some watermarked images undergo additional degradation. Proposed methodologywill be improved using more sophisticated fingerprint verification methods and subsequently incorporated into multimodal watermarking schemes.

A Fingerprint-Based Digital Images Watermarking for Identity Authentication

In this paper the combination of fingerprint verification methods with watermarkingtechnology to provide copyright protection and authentication of digital images is proposed. The goalof this study is to investigate how watermarking processing affects the quality of biometric watermarks.Performed experiments showed that extracted fingerprint images have roughly equal verification performance even if some watermarked images undergo additional degradation. Proposed methodologywill be improved using more sophisticated fingerprint verification methods and subsequently incorporated into multimodal watermarking schemes.