Image Watermarking Technique Research Articles

Histogram Modification and Wavelet Transform for High Performance Watermarking

This paper proposes a reversible watermarking technique for natural images. According to the similarity of neighbor coefficients’ values in wavelet domain, most differences between two adjacent pixels are close to zero. The histogram is built based on these difference statistics. As more peak points can be used for secret data hiding, the hiding capacity is improved compared with those conventional methods. Moreover, as the differences concentricity around zero is improved, the transparency of the host image can be increased. Experimental results and comparison show that the proposed method has both advantages in hiding capacity and transparency.

Fast and High Capacity Digital Image Watermarking Technique Based on Phase of Zernike Moments

Zernike Moments (ZMs) are used in many image processing applications, due to their resistance against various signal processing and geometric attacks. Digital image watermarking is one of those application areas, where ZMs are widely used to insert and extract the watermark bits for digital media authentication. In all the existing ZM based watermarking techniques, magnitude of moments is used to insert and extract the watermark. In this paper, the authors’ have proposed a semi blind watermarking technique in which phase of ZMs is used for watermark insertion and extraction. Due to the use of phase of ZMs, 100% detection ratio is achieved against any geometric and other signal processing attacks. To make the proposed technique fast, q-recursive method is used to compute the Zernike polynomials. The use of q-recursive method has also increased the transparency of watermark due to its better reconstruction ability as compared to traditional moment computation method. Through detailed experimentation, it has been confirmed that the proposed watermarking technique is fast, has more imperceptibility, less Bit Error Rate (BER) and more capacity as compared to traditional ZMs magnitude based watermarking technique.

An Artificial Intelligent Technique for Robust Digital Watermarking in Multiwavelet Domain

In this paper, an artificial intelligent technique for robust digital image watermarking in multiwavelet domain is proposed. The embedding technique is based on the quantization index modulation technique and the watermark extraction process does not require the original image. We have developed an optimization technique using the genetic algorithms to search for optimal quantization steps to improve the quality of watermarked image and robustness of the watermark. In addition, we construct a prediction model based on image moments and back propagation neural network to correct an attacked image geometrically before the watermark extraction process begins. The experimental results show that the proposed watermarking algorithm yields watermarked image with good imperceptibility and very robust watermark against various image processing attacks. Keywords—Watermarking, Multiwavelet, Quantization index modulation, Genetic algorithms, Neural networks.

A Neural Watermark Approach

In this paper we propose the coupling of a watermarking technique for images, called least significant bit, in the multiple classes random neural network. For that, we design a training process of the watermark pattern, an embedding process of the learned pattern in the original image, and a detecting process of this pattern in the carrier image. The removal of the watermark is not considered in this work, since the aim is to study the capability of detection of our neural approach of any manipulation over the carrier image. We define several attacks to compare the robustness of our approach with previous works (rotation, JPEG compression, scaling, noise, cropping, Horizontal Flip, Brightness and contrast correction), obtaining very good results with our approach. Additionally, we obtain very good performances in terms of the Peak Signal to Noise Ratio and Noise Generated criteria.

Hierarchical encrypted image watermarking using fractional Fourier domain random phase encoding

In this paper, a hierarchical encrypted image watermarking technique based on a fractional domain random phase encoding method is proposed. Multiple watermarks encrypted at multiple levels are mul- tiplexed in the fractional Fourier domain and added into a host image. The watermarks are encrypted by the conventional fractional Fourier do- main double random phase encoding scheme. The proposed method offers extra security. The invisible watermark is recovered by applying correct random phase masks along with the correct fractional orders. The metric peak signal-to-noise ratio is used to evaluate the visual qual- ity of the watermarked image. To check the robustness of the proposed technique, the effects of image processing operations, such as cropping, meanfiltering, medianfiltering, and noise, are also studied. For watermark authentication, the correlation value is calculated between the original and retrieved watermarks. Simulation results are presented in support of the proposed idea. C

Comparative Analysis of Normalization based Image Watermarking Techniques

This paper presents a comparative study of watermarking schemes. The embedding of watermark is performed after the image normalization. By normalization process the normalized image achieves invariance properties against geometric attacks which include rotation, scaling and translation of an image. Watermarking is done using five methods DCT Zigzag, DCT blocks, DWT, Zernike transform, SVD-DCT. Similarity measures are calculated in order to compare the five watermarking schemes.

AN ADAPTIVE DIGITAL IMAGE WATERMARKING USING FUZZY GRADIENT ON DCT DOMAIN

In this paper, an adaptive digital image watermarking technique using fuzzy gradient on DCT domain is presented. In our approach, the image is divided into separate blocks and the DCT is applied on each block individually. Then, the watermark is inserted in the transform domain and the inverse transform is carried out. We increase the robustness of the watermark by increasing the watermark strength. However, this reduces the fidelity of the watermarking scheme. This is because the fidelity and robustness of watermarking are generally in conflict with each other. To improve the fidelity, a new fuzzy-based method is introduced. In this method, a fuzzy gradient-based mask is generated from the host image. Then, as a post-processing stage, the generated mask is combined with the watermarked image. Experimental results show that the proposed technique has high fidelity as well as high robustness against a variety of attacks.

Oblivious Image Watermarking in Discrete Multiwavelet Domain using QIMM

This paper proposes a novel oblivious image watermarking technique for the copyright protection and authentication of still images, based on Discrete Multiwavelet Transform (DMWT) and Quantization Index Modulus Modulation (QIMM). The multiwavelet coefficients of an image are quantized using QIMM and the coefficients are modified according to the binary watermark logo. Watermark extraction does not require the original image. Experimental results show that, the proposed watermarking scheme is robust to image compression and rotational attacks. It is superior to the method proposed by Lin et al. [10] in terms of Peak Signal to Noise Ratio (PSNR) and Bit Error Rate (BER).

Blind dewatermarking method based on wavelet transform

Along with the improvement of image watermarking techniques, the necessity for effectively and comprehensively evaluating various algorithms becomes imperative. In this paper, we first propose a new categorization that fits for most of the existing watermarking algorithms that work in the wavelet domain. Then an adaptive watermarking attack for evaluating the robustness of watermarking schemes that are based on the proposed categorization is presented. This attack determines the flat regions, edges, and textures of the watermarked image and based on known features of each region the proposed attack tries to destroy the watermark information. This is done by separately manipulating the wavelet coefficients of each region such that the least visual distortion will be imposed on the attacked image. We study some recent watermarking techniques in terms of the watermark invisibility and robustness through subjective experiments and objective metrics. The average peak signal-to-noise ratio (PSNR) of the watermarked image after applying the proposed attack is more than 35 dB and the average normalized cross correlation (NC) for the extracted watermark is lower than 0.4, so theoretically, the watermark is not detectable. Moreover, the proposed method does not consider any knowledge about the underlying watermarking algorithm.

DCT영역에서 스크램블된 이진 위상 컴퓨터형성홀로그램을 이용한 디지털 영상 워터마킹 기술

본 논문에서는 DCT 영역에서 스크램블된 이진 위상 컴퓨터형성홀로그램을 이용한 디지털 영상 워터마킹 기술을 제안하였다. 워터마크 삽입과정은 워터마크로 사용되는 은닉영상 대신 은닉영상을 손실 없이 재생할 수 있는 이진 위상 컴퓨터홀로그램을 생성하고 이를 스크램블기법으로 암호화 하여 워터마크로 사용한다. 그리고 암호화된 워터마크에 가중치 함수를 곱하고 호스트영상의 DCT 영역에서 DC성분에 삽입한 후 IDCT를 수행한다. 워터마크의 추출은 워터마킹된 영상과 원래의 호스트영상의 DCT계수 차이를 구하고, 삽입시 적용한 가중치 함수를 나눈 후 디스크램블링 하여 복호화 한다 그리고 복호화된 워터마크를 역푸리에 변환하여 은닉영상을 재생한다 마지막으로 원래의 은닉영상과 복호화된 은닉영상과의 상관을 통해 워터마크의 존재여부를 결정한다. 제안된 워터마킹 기술은 이진 값으로 구성된 은닉영상의 홀로그램정보를 이용하고 스크램블링 암호화 기법을 활용하였음으로 기존의 어떠한 워터마킹 기술보다 압축, 잡음 및 절단과 같은 다양한 외부공격에 안전하고 견실한 특징을 가지고 있음을 컴퓨터시뮬레이션을 통해 그 장점들을 확인하였다. In this paper, we proposed a digital image watermarking technique using scrambled binary phase computer generated hologram in the discrete cosine transform(DCT) domain. For the embedding process of watermark. Using simulated annealing algorithm, we would generate a binary phase computer generated hologram(BPCGH) which can reconstruct hidden image perfectly instead of hidden image and encrypt it through the scramble operation. We multiply the encrypted watermark by the weight function and embed it into the DC coefficients in the DCT domain of host image and an inverse DCT is performed. For the extracting process of watermark, we compare the DC coefficients of watermarked image and original host image in the DCT domain and dividing it by the weight function and decrypt it using descramble operation. And we recover the hidden image by inverse Fourier transforming the decrypted watermark. Finally, we compute the correlation between the original hidden image and recovered hidden image to determine if a watermark exits in the host image. The proposed watermarking technique use the hologram information of hidden image which consist of binary values and scramble encryption technique so it is very secure and robust to the various external attacks such as compression, noises and cropping. We confirmed the advantages of the proposed watermarking technique through the computer simulations.

A Study on Digital Image and Video Watermarking Schemes using Neural Networks

The use of computer network communication makes information exchange and transmission relatively simple and quick. But with digital image, audio and video products like multimedia, copyright protected security questions will be exposed in such communication environments. Digital watermarks have been recently proposed for authentication of both video and still images. This paper gives a review of a few of the proposed image and video watermarking techniques using neural networks.

Comparative Performance Analysis of DWT-SVD BasedColor Image Watermarking Technique in YUV, RGB and YIQ Color Spaces

In this paper, robust color image watermarking technique based on discrete wavelet transform-singular value decomposition (DWT-SVD) with Arnold scrambling is proposed and tested with YUV, RGB and YIQ color spaces. The PSNR and NC are compared for YUV, RGB and YIQ color spaces and complete analysis is presented. The decomposition is done with 'Haar' which is simple, symmetric and orthogonal wavelet and the direct weighting factor is used in watermark embedding and extraction process. The results are tested with standard database color images of size 512ൈ512 and grey scale watermark of 64ൈ64 sizes. The presented scheme is non blind. The maximum recorded PSNR is 53.1701 for R channel and up to 52.3337 for Y channel and maximum value of NC equal to 0.9997 for U channel and average value remains 0.99 indicating best recovery of watermark for all channels. The proposed scheme is also tested for different attacks like compression, scaling, rotation, cropping noise etc in YUV, RGB and YIQ color spaces and comparative results are presented.

Digital Image Watermarking Technique Based on Different Attacks

Digital watermarking is used to hide the information inside a signal, which cannot be easily extracted by the third party. Its widely used application is copyright protection of digital information. It is different from the encryption in the sense that it allows the user to access, view and interpret the signal but protect the ownership of the content. One of the current research areas is to protect digital watermark inside the information so that ownership of the information cannot be claimed by third party. With a lot of information available on various search engines, to protect the ownership of information is a crucial area of research. In recent year, several digital watermarking techniques are presented based on discrete cosine transform (DCT), discrete wavelets transform (DWT) and discrete fourier transforms (DFT). In this paper, we proposed an algorithm for digital image watermarking technique based on singular value decomposition; both of the L and U components are explored for watermarking algorithm. This technique refers to the watermark embedding procedure and watermark extracting procedure. Digital image watermarking techniques for copyright protection is robust. The experimental results prove that the quality of the watermarked image is good and that there is strong resistant against many attacks. The image watermarking techniques help to achieve artificial intelligence. Digital image watermarking is the most effective solution in this area and its use to protect the information is increasingly exponentially day by day.

On Secure Digital Image Watermarking Techniques

Digital watermarking is used to hide the information inside a signal, which can not be easily extracted by the third party. Its widely used application is copyright protection of digital information. It is different from the encryption in the sense that it allows the user to access, view and interpret the signal but protect the ownership of the content. One of the current research areas is to protect digital watermark inside the information so that ownership of the information cannot be claimed by third party. With a lot of information available on various search engines, to protect the ownership of information is a crucial area of research. In latest years, several digital watermarking techniques are presented based on discrete cosine transform (DCT), discrete wavelets transform (DWT) and discrete fourier transforms (DFT). In this paper, we propose an algorithm for digital image watermarking technique based on singular value decomposition; both of the L and U components are explored for watermarking algorithm. This technique refers to the watermark embedding algorithm and watermark extracting algorithm. The experimental results prove that the quality of the watermarked image is excellent and there is strong resistant against many geometrical attacks.

A DWT based Dual Image Watermarking Technique for Authenticity and Watermark Protection

A DWT based Dual Image Watermarking Technique for Authenticity and Watermark Protection

Wavelet-based image watermarking with visibility range estimation based on HVS and neural networks

This work proposes a wavelet-based image watermarking (WIW) technique, based on the human visible system (HVS) model and neural networks, for image copyright protection. A characteristic of the HVS, which is called the just noticeable difference (JND) profile, is employed in the watermark embedding to enhance the imperceptibility of the technique. First, we derive the allowable visibility ranges of the JND thresholds for all coefficients of a wavelet-transformed image. The WIW technique exploits the ranges to compute the adaptive strengths to be superimposed in the wavelet coefficients while embedding watermarks. An artificial neural network (ANN) is then used to memorize the relationships between the original wavelet coefficients and its watermark version. Consequently, the trained ANN is utilized for estimating the watermark without the original image. Many existing schemes require the original image to be involved in the calculation of the JND profile of the image. Finally, computer simulations demonstrate that both transparency and robustness of the WIW technique are superior to that of other proposed methods.

Color image watermarking based on self-embedded color permissibility with preserved high image quality and enhanced robustness

A robust wavelet-based blind technique for color image watermarking is proposed denoted as color image watermarking using self-embedded color permissibility (CIW-SECP) is proposed. CIW-SECP technique is based on embedding two watermarks in a spread-spectrum fashion in the U and V planes of the YUV color space. The watermark weights are generated based on the so-called “color permissibility” of the U and V planes. These weights are generated and self-embedded in the relative U and V planes based on the color characteristics of the image under question. Experimental results have shown that the CIW-SECP technique exhibits very high imperceptibility (PSNR∈[71.21–85.95] dB) as well as superior performance against most prominent attacks.

A digital robust image watermarking against desynchronization attacks

In this paper, a robust image watermarking technique using support vector regression (SVR) and particle swarm optimization is introduced to protect intellectual property rights of the gray images in discrete cosine transform domain against a variety of desynchronization attacks. After the division of the original image to 8 × 8 non-overlapping blocks, frequency coefficients of each block are found using discrete cosine transform. Positions of the inputs and output, among the low frequency coefficients which have the significant characteristics of the image, which are used to train SVR are obtained by using particle swarm optimization technique. After SVR is trained using the obtained positions of the inputs and output, watermark embedding and extracting processes are implemented using the trained SVR. Experiments implemented using the optimized coefficients selected among low frequency coefficients show that our watermarking technique has better watermark extracting success after the desynchronization attacks. Key words: Robust image watermarking, support vector regression, particle swarm optimization.

Nonblind and Quasiblind Natural Preserve Transform Watermarking

This paper describes a new image watermarking technique based on the Natural Preserving Transform (NPT). The proposed watermarking scheme uses NPT to encode a gray scale watermarking logo image or text, into a host image at any location. NPT brings a unique feature which is uniformly distributing the logo across the host image in an imperceptible manner. The contribution of this paper lies is presenting two efficient nonblind and quasiblind watermark extraction techniques. In the quasiblind case, the extraction algorithm requires little information about the original image that is already conveyed by the watermarked image. Moreover, the proposed scheme does not introduce visual quality degradation into the host image while still being able to extract a logo with a relatively large amount of data. The performance and robustness of the proposed technique are tested by applying common image-processing operations such as cropping, noise degradation, and compression. A quantitative measure is proposed to objectify performance; under this measure, the proposed technique outperforms most of the recent techniques in most cases. We also implemented the proposed technique on a hardware platform, digital signal processor (DSK 6713). Results are illustrated to show the effectiveness of the proposed technique, in different noisy environments.

Multi-channel watermarking scheme based on HVS for color image in DCT domain

A blind watermarking algorithm for digital image based on Discrete Cosine Transform (DCT) was proposed. First,the original image was transformed from RGB color space into YCbCr color space,which has excellent independence of every channel,and then the watermarking was embedded into all three color spaces. Secondly,the watermarking was embedded by image watermarking technique of DCT,and the embedding capacity depended on Human Visual System (HVS). The experimental result indicates that the algorithm is visually imperceptible and robust to general image processing.