AUTHENTICATION OF DIGITAL IMAGE BASED ON DWT-SVD AND TA

Digital watermarking is a process in which data can be hide into other image or audio or document. This data can be anything like secret data or it may be data which provides authenticity. Data can be hide in spatial or in frequency domain. since frequency domain technique is more robust against different kind of signal and non-signal processing attacks. And watermark can be extracted by blind or non-blind techniques.in this paper we proposed blind image watermark techniques and watermark is embedded using frequency domain using discrete wavelet transform, singular value decomposition and torus automorphism technique. This method proves that it is robust against different signal and non-signal processing attacks and watermark can be extracted without cover image

Hiding data in images using steganography techniques with compression algorithms

Steganography is the science and art of secret communication between two sides that attempt to hide the content of the message. It is the science of embedding information into the cover image without causing a loss in the cover image after embedding.Steganography is the art and technology of writing hidden messages in such a manner that no person, apart from the sender and supposed recipient, suspects the lifestyles of the message. It is gaining huge attention these days as it does now not attract attention to its information's existence. In this paper, a comparison of two different techniques is given. The first technique used Least Significant Bit (LSB) with no encryption and no compression. In the second technique, the secret message is encrypted first then LSB technique is applied. Moreover, Discrete Cosine Transform (DCT) is used to transform the image into the frequency domain. The LSB algorithm is implemented in spatial domain in which the payload bits are inserted into the least significant bits of cover image to develop the stego-image while DCT algorithm is implemented in frequency domain in which the stego-image is transformed from spatial domain to the frequency domain and the payload bits are inserted into the frequency components of the cover image.The performance of these two techniques is evaluated on the basis of the parameters MSE and PSNR

On Block Representations in Image Processing Problems

Any orthogonal transformation of the digital grayscale image can be represented by a set of images to be an orthonormal basis. For such representation digital data scattering was considered that is important in applications, particularly for the robust watermarking techniques. We introduce a block matrix, elements of which are basis images. This matrix is found to be useful for representation of multi-dimensional arrays, that can describe a set of digital images. This representation has new features concerning the data scattering. A steganographic scheme for frequency domain watermarking based on this representation is considered

A ROBUST NON-BLIND HYBRID COLOR IMAGE WATERMARKING WITH ARNOLD TRANSFORM

Due to development of the internet technologies and other services, requirement of rightful ownership and copyright is highly required. Hence to protect the copyrighted data from unauthorized user, a robust non-blind hybrid color image watermarking scheme is presented. In this proposed scheme, we use color watermark instead of gray watermark which is generally used in most of the existing digital image watermarking techniques. YCbCr color space used to separate the R, G and B channel of images. Y channel of color watermark is embedded into corresponding Y channel of cover image using proposed scheme. Arnold transform are used to scramble the watermark image before embedding process in order to provide more security. The singular value of bands is going to embed with singular values of watermark by making use of variable scaling factor (a). As original image is required at the time of extraction of watermark hence propose scheme belong to non-blind technique group. The two-fidelity parameter namely Peak signal to noise ratio (PSNR) and structural similarity (SSIM) index are used to measure the imperceptibility whereas similarity between original and extracted watermark is measured by using normalized correlation coefficient (NCC). We also compared the results of proposed scheme with other existing watermarking schemes. The experimental results prove effectiveness of the proposed image watermarking scheme in term of robustness and imperceptibility

On the security of a hybrid SVD-DCT watermarking method based on LPSNR

Watermarking schemes allow a cover image to be embedded with a watermark, for diverse applications including proof of ownership and covert communication. In this paper, we present attacks on watermarking scheme proposed by Huang and Guan. This scheme is hybrid singular value decomposition (SVD) based scheme in the sense that they employ both SVD and other techniques for watermark embedding and extraction. By attacks, we mean that we show how the designers’ security claim, related to proof of ownership application can be invalidated. Our results are the first known attacks on this hybrid SVD-based watermarking scheme. Advances in Image and Video Technology Advances in Image and Video Technology Look Inside Share Share this content on Facebook Share this content on Twitter Share this content on LinkedIn Other actions Export citations About this Book Reprints and Permission