An Optimized Color Image Watermarking Technique Using Differential Evolution and SVD–DWT Domain

In this paper, we propose a robust watermarking technique which combines features of Discrete wavelet transformation (DWT), discrete cosine transformation and singular value decomposition. In this technique DWT is used to decompose the color images into various frequency and time scale. Block DCT is applied on DWT coefficients of various frequency to provide high level of robustness. DCT transformed blocks of size 4x4 are further decomposed using dual SVD technique to get singular values in which watermark is to be hidden. Algorithm is tested using Lena test image in RGB and YIQ color model. As per the results combining feature of DWT-DCT with SVD technique provides robustness against image processing and geometric attacks in YIQ color model than RGB color model.

Watermarking is a useful technique for copyright management. It is widely used in various types of digital content management application of grayscale and colour images. But as of now, there has been no method to watermark for a grayscale image using a colour image. In this paper, a unique watermarking for the grayscale image scheme in the transform domain has been proposed. The presented technique is suitable for the digital rights and security management of the diagnostic medical images in the online database. The proposed watermarking method is composed of Discrete Wavelet Transform (DWT) and Singular Value Decomposition (SVD). Additionally, we have used the Firefly Algorithm (FA) to compute appropriate scaling factor to achieve higher perceptibility and robustness. Performance metrics such as PSNR, SSIM, and NCC are used to evaluate the technique. Experimental analysis shows that the proposed technique is 40-45% improved over the existing methods and almost 50% watermark is recoverable under different image processing attacks proving robustness of the technique.

In this paper, a new robust and secure video watermarking scheme based on discrete Wavelet Transform (DWT), singular value decomposition (SVD), and Laplacian pyramid is proposed for copyright protection applications. The main contributions of this work are: 1) Increasing watermark robustness towards common signal processing attacks by separating the watermark image into a high-frequency image and a low-frequency image using laplacian pyramid. Then, the singular values of each of the low-frequency watermark image and the high-frequency watermark image are hidden in two different DWT subbands of the original video frame. Separating the watermark and hiding its two parts in two different subbands of the DWT of the video frame makes it robust towards noise, filtering, and compression attacks. 2) Improving the quality of the extracted watermarks via correcting the received watermarked videos using SURF points when those videos are geometrically attacked, mainly by rotation, scaling, and shear attacks. 3) Increasing security and avoiding false positive problems (FPP) associated with SVD by using perceptual image hashing in the proposed scheme. Through experimental results and comparisons to other techniques, the proposed scheme has shown very high imperceptibility for the tested watermarked videos in terms of peak signal to noise ratio (PSNR). Also, the proposed scheme has demonstrated high watermark robustness towards various types of attacks, and an improvement in the quality of the extracted watermarks from 4 to 20 dB compared to other techniques.

An enhanced hybrid image watermarking scheme for security of medical and non-medical images based on DWT and 2-D SVD

Digital image watermarking serves as a tool for protection of ownership of the media shared on common platform. This paper presents a robust, blind watermarking technique for colour images based on singular value decomposition (SVD) and discrete wavelet transform (DWT). Watermark is embedded in mid-frequency sub-bands of two-level DWT. These sub-bands are divided into non-overlapping blocks of size 4 × 4, each of which undergoes SVD. The singular values (SV) are updated based on watermark bit and using Lagrange's optimisation principle using two keys. Experiments show that the proposed technique is imperceptible with PSNR > 40 dB. Also, the technique can resist general image processing operations (attacks) on the images with the structural similarity index measure (SSIM) nearly 1 and sufficiently high bit correct ratio (BCR).

Most Discrete Wavelet Transform(DWT)/Singular Value Decomposition(SVD) watermark methods are robust to common attacks, such as loss compression, noise and filtering attacks, but they cannot resist geometrical attacks. As Scale Invariant Feature Transform(SIFT) feature points are invariant to rotation, scaling and translation, a blind DWT-SVD watermark method against geometrical attacks based on SIFT is proposed. The square of the inscribed circle of the host image matrix is chosen as the watermark embedding area. Firstly, the watermark embedding area is decomposed with 1-level DWT and the low-frequency sub-band is divided into non-overlapping blocks; then the SVD is applied to every block. Secondly, the watermark is embedded by quantifying the maximum singular value of each block. Finally, SIFT feature points of the watermarked image are saved to detect and correct possible geometrical attacks. The experimental results show that the proposed method not only has the robustness to any angle of rotation attacks, wide range of scaling attacks and translation attacks, but also can achieve blind extraction.

Efficient video watermarking based on singular value decomposition in the discrete wavelet transform domain

This paper proposes novel robust multiple watermarking technique for color images in spatial domain. The host image is divided into four different regions. Each region consists of four 128*128 blocks in order to hide a watermark. The watermark is a binary image, encrypted and embedded into different regions of the blue component of the host image by altering intensity values of the selected region. Five watermarks can be extracted by comparing the intensities of the selected region of the original image with the corresponding region of the watermarked image. The extracted watermark bits can be determined by calculating the probability of detecting '0' or '1'. Only one watermark will be selected or built from the five extracted watermarks according to the highest value of the normalized cross correlation (NCC). The proposed watermarking technique is shown to be robust for a wide range of attacks, including JPEG2000, JPEG compression, rotation, cropping, scaling, self-similarity, rotation-scaling, rotation-cropping and filtering.

The main problem in using various watermarking methods to secure digital images is how to optimize the trade-off between robustness watermarked image against the effect of distortion and imperceptibility on watermark insertion. This research proposes a watermark insertion method to protect copyright in true color (RGB) images by combining Discrete Wavelet Transform (DWT) and Singular Value Decomposition (SVD) algorithms. DWT process will be done as much as 2 levels then selected subband LL2 to inserted watermark by Singular Value Decomposition (SVD) method. Measuring tool in this research using MSE, PSNR, SSI M for imperceptibility and NC quality measurement for robustness measurement. The results show that the proposed scheme can optimize the trade-off between imperceptibility and robustness. Some attacks are used such as Gaussian noise, salt & pepper noise, crop, blur and rotate for watermarked image resilience. The PSNR and SSIM values produced from this method are fairly stable values above 40 dB for PSNR and above 0.99 for SSIM. While the average value of NC resulting from this method is 1.

Digital image watermarking is one of the largest research fields, and it plays a vital role in digital information authentication and security. Based on the study of watermarking systems, the whole process may be segregated into the processes of watermark embedding and extraction. In this paper, a review of the theoretical and experimental analysis and performance measurement of representative digital image watermarking systems in spatial and transform domains is presented. The significant characteristics of the digital image watermarking scheme are robustness, capacity, imperceptibility, the security of the hiding place, and false-positive of the watermarking algorithm. Comparison of the different watermarking techniques such as the least significant bit (LSB), singular value decomposition (SVD), the discrete wavelet transform (DWT), and the discrete cosine transform (DCT) is presented in a tabular form. A detailed discussion along with an algorithm for digital image encryption/decryption through embedding and extraction is given. A brief comparison of their relative advantages and disadvantages is also noted in this paper.KeywordsInformation hidingWatermarkingSecurityAttacksRobust

This paper presents a new robust hybrid multiple watermarking technique using fusion of discrete wavelet transforms (DWT), discrete cosine transforms (DCT), and singular value decomposition (SVD) instead of applying DWT, DCT and SVD individually or combination of DWT-SVD / DCT-SVD. For identity authentication purposes, multiple watermarks are embedded into the same medical image / multimedia objects simultaneously, which provides extra level of security with acceptable performance in terms of robustness and imperceptibility. In the embedding process, the cover image is decomposed into first level discrete wavelet transforms where the A (approximation/lower frequency sub-band) is transformed by DCT and SVD. The watermark image is also transformed by DWT, DCT and SVD. The S vector of watermark information is embedded in the S component of the cover image. The watermarked image is generated by inverse SVD on modified S vector and original U, V vectors followed by inverse DCT and inverse DWT. The watermark is extracted using an extraction algorithm. Furthermore, the text watermark is embedding at the second level of the D (diagonal sub-band) of the cover image. The security of the text watermark considered as EPR (Electronic Patient Record) data is enhanced by using encryption method before embedding into the cover. The results are obtained by varying the gain factor, size of the text watermark, and cover medical images. The method has been extensively tested and analyzed against known attacks and is found to be giving superior performance for robustness, capacity and reduced storage and bandwidth requirements compared to reported techniques suggested by other authors.

Digital Image Watermarking provides a successful method for content authentication and copyright protection. Thus, it has significant scope in today's era due to the rapid growth of internet users. The watermark should be robust and reliable in addition to being imperceptible to the human eye. In this paper, a hybrid singular value decomposition (SVD) and discrete wavelet transform (DWT) based watermarking scheme is presented. The SVD used in this scheme is a variant of the traditional SVD and is called shuffled SVD (SSVD). The cover image is decomposed into four sub-bands (LL, HL, LH, HH) using DWT. The LL subband is further divided into blocks of appropriate size. The principle components of the watermark image obtained after applying SSVD are embedded in various blocks of the LL sub-band. The proposed scheme shows significant robustness in addition to being false positive free.

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.

A novel secure and robust image watermarking technique for color images is presented in this paper. Besides robustness and imperceptibility (which are the most important requisites of any watermarking scheme), there are two other challenges a good watermarking scheme must meet: security and capacity. Therefore, in devising the presented scheme, special consideration is also given to above-mentioned requirements. In order to do so, principal component analysis is involved to enhance imperceptibility and the unique utilization of singular value decomposition is done to achieve better performance in regard to capacity and robustness. Finally, a novel method is proposed to select constituents of an image for watermark embedding, which further improves the security. As a consequence, four essential requisites of a good watermarking scheme are achieved as visible from experimental results. To measure the behavior of presented watermarking scheme, a number of experiments were conducted by utilizing several color images as host images and as watermarks. The presented technique is compared with the latest available watermarking techniques and attained better results than them.

The presence of duplicated regions in the image can be considered as a tell-tale sign for image forgery, which belongs to the research field of digital image forensics. In this paper, a blind forensics approach based on DWT (discrete wavelet transform) and SVD (singular value decomposition) is proposed to detect the specific artifact. Firstly, DWT is applied to the image, and SVD is used on fixed-size blocks of low-frequency component in wavelet sub-band to yield a reduced dimension representation. Then the SV vectors are then lexicographically sorted and duplicated image blocks will be close in the sorted list, and therefore will be compared during the detection steps. The experimental results demonstrate that the proposed approach can not only decrease computational complexity, but also localize the duplicated regions accurately even when the image was highly compressed or edge processed.