Watermark Data Research Articles

Comparison of DCT, SVD and BFOA based multimodal biometric watermarking systems

Digital image watermarking is a major domain for hiding the biometric information, in which the watermark data are made to be concealed inside a host image imposing imperceptible change in the picture. Due to the advance in digital image watermarking, the majority of research aims to make a reliable improvement in robustness to prevent the attack. The reversible invisible watermarking scheme is used for fingerprint and iris multimodal biometric system. A novel approach is used for fusing different biometric modalities. Individual unique modalities of fingerprint and iris biometric are extracted and fused using different fusion techniques. The performance of different fusion techniques is evaluated and the Discrete Wavelet Transform fusion method is identified as the best. Then the best fused biometric template is watermarked into a cover image. The various watermarking techniques such as the Discrete Cosine Transform (DCT), Singular Value Decomposition (SVD) and Bacterial Foraging Optimization Algorithm (BFOA) are implemented to the fused biometric feature image. Performance of watermarking systems is compared using different metrics. It is found that the watermarked images are found robust over different attacks and they are able to reverse the biometric template for Bacterial Foraging Optimization Algorithm (BFOA) watermarking technique.

Robust medical image watermarking technique for accurate detection of tampers inside region of interest and recovering original region of interest

Transmission of medical images among remote places is a general practice in telemedicine. Medical images may be modified intentionally or accidentally as the transmission of these may take place through unsecure networks such as internet. Before making any diagnostic decisions, the medical practitioner has to verify the integrity of region of interest (ROI) in the received medical image in order to avoid wrong diagnosis. Watermarking can be used for checking the integrity of medical images. In this study, the authors propose a novel medical image watermarking method based on integer wavelet transform (IWT). This proposal verifies the integrity of ROI, precisely identifies tampered blocks inside ROI, provides robustness to the data embedded inside region of non-interest (RONI) and recovers original ROI. In the proposed method, the medical image is segmented into ROI and RONI regions. Hash value of ROI, recovery data of ROI and data of patient are embedded into RONI using IWT. Experimental results show that the proposed method provides robustness to the watermark data embedded inside RONI and accurately detects and localises tampered areas inside ROI and recovers the original ROI.

SECURE VIDEO WATERMARKING ALGORITHM BASED ON WAVELET WITH MULTIPLE WATERMARKS

Watermarking is the new advancement that perceives to make clear the issue of unlawful control and dispersion of the data. In our proposed framework, primary secret information is grouped into alternative pixels shares and secondary watermark is concealed in one of the flipped shares. Further rearrange the concealed shares into normal form and stack the allotments into a single image. Now the primary watermarked image is sectioned into various pieces and hidden the piece of watermarked information into specific frames under wavelet. Accordingly the watermark data is requested for with acceptably with the human visual framework which makes them imperceptible. Concealed information is less perceivable and also robust against regular video processing attacks.

Assessment of distortion in watermarked geospatial vector data using different wavelets

With the rapid growth of the Internet, the copyright protection problem occurs frequently, and unauthorized copying and distributing of geospatial data threaten the investments of data producers. Digital watermarking is a possible solution to solve this issue. However, watermarking causes modifications in the original data resulting in distortion and affects accuracy, which is very important to geospatial vector data. This article provides distortion assessment of watermarked geospatial data using wavelet-based invisible watermarking. Eight wavelets at different wavelet decomposition levels are used for accuracy evaluation with the help of error measures such as maximum error and mean square error. Normalized correlation is used as a similarity index between original and extracted watermark. It is observed that the increase in the strength of embedding increases visual degradation. Haar wavelet outperforms the other wavelets, and the third wavelet decomposition level is proved to be optimal level for watermarking.

A Novel Authentication Scheme for Lossy Compressed Images

In this paper, a novel scheme is proposed for watermarking lossy compressed images just before transmission and authenticating them once they are received, away from the core of the compression and de-compression processes. The scheme is inserted into the Joint Photographic Expert Group (JPEG) structure that is encoded using the Discrete Cosine Transform (DCT) at specified locations. The watermark information is extracted from and embedded into specified DCT coefficients, following novel criteria. The scheme is robust to lossy compression; though it is fragile, exposing any slight changes of the probe images. The scheme is also blind, needs no prior information about the original image or the watermark information to authenticate the received image. Experimentally, if the received watermarked data is not manipulated, the proposed scheme verifies them as ‘authenticated’. On the other side, if geometrical or image processing attacks are applied to the watermarked images, they are then verified successfully as ‘not authenticated’. The proposed scheme is further evaluated and compared to similar authentication schemes. The noise added to the original image due to embedding the watermark information is 0.063 dB (decibel), overcoming all results in the reviewed literature.

A Novel Watermarking Method for Synchronous Transmission of Gong-Che Notation Score and its MIDI Information

In this paper, a new watermarking algorithm to realize synchronous transmission of Gong-Che Notation musical score image and its MIDI information was been present. Firstly, it transforms the MIDI information to a sequence of 0 1 codes which is the watermarking data, then it embeds the watermarking data into the Gong-Che Notation musical score image by clockwise inward rotating order, finally, it judges whether the Gong-Che Notation musical score image need expand to avoid loss musical information by computing number of connected component labeling. Experiments shows that the expanded times are no more than Len(M(2))/(2H*W).

Design and Analysis of Efficient Blind Reversible Watermarking Technique

This paper proposes a blind reversible watermarking techniquewhich incorporates the histogram shifting in wavelet domain. The integer wavelet transform is used to transform the image into wavelet domain. The watermark data is embedded into the sub-band coefficients identified by just noticeable distortion (JND)of the transformed host image. To ensure the prohibition of pixel overflow and underflow in spatial domain property inspired pixel adjustment (PIPA) is also employed, finally wavelet-domain statistical quantity histogram shifting and clustering are used for improving robustness and reducing run-time complexity of the extracting process. The experimental results demonstrate predominance of the proposed approach for different host and watermark images. It also demonstrate the efficient recovery of both watermark and host image.

Data quality evaluation in medical database watermarking.

The use of watermarking in the protection of medical relational databases requires that the introduced distortion does not hinder records interpretation. In this paper, we present the preliminary results of a watermarked data quality evaluation protocol developed so as to analyze the perception the practitioner has of the watermark. These results show that some attributes are more appropriate for watermarking than others and also that incoherent or unlikely records resulting from careless watermarking are easily identified by an expert.

QR code based blind digital image watermarking with attack detection code

A QR code based blind digital image watermarking technique with an attack detection feature is described here. The technique describes a key based framework to incorporate image, server port address or website address as watermark data; which increases the extended usability of the embedded data and the adaptability of the verification application. The watermarking problem is formulated as a signal communication problem with watermark data representation, embedding of watermark and attack detection as a source encoding, channel encoding and attenuation detection problems respectively. The mathematical aspects of the respective signal processing problems are extended to digital image watermarking with sufficient background support. The use of QR code ensures extended usability, while the application specific watermark data achieves adaptability of the verification application. The QR code is embedded into the attack resistant HH component of 1st level DWT domain of the cover image and to detect malicious interference by an attacker, a unique image registry code generated from the high frequency structural components of the stego-image is used. The key based approach and the attack resistant embedding domain makes this method robust against visually invariant attacks. The testing results show the compliance of the method with all the proposed aspects.

Robust copyright protection using multiple ownership watermarks.

Generally, conventional transform (DWT and DFT, etc.) -based watermarking techniques provide only one spectrum plane for embedding the watermark, thus the embedding watermark information can be easily removed. To solve this problem, we propose an efficient cellular automata (CA) based watermarking method that CA transform (CAT) with various gateway values can provide many transform planes for watermark embedding according to various CA rules. In this paper, multiple ownership watermarks are first recorded in the form of an elemental image array (EIA), simultaneously, and then the recorded EIA as the watermark data is embedded into the CAT coefficient. An additional advantage of this proposed method is that EIA is composed of many elemental images and each elemental image has its own property of watermarks. Even though most data of elemental images are lost, the watermarks can be reconstructed from the remaining elemental images successfully. Experimental results show that the proposed technique provides good image quality and is robust in varying degree to some image processing attacks.

A survey on reversible watermarking techniques for relational databases

AbstractOver the past few years, reversible watermarking techniques for relational databases have been proposed to provide protection of ownership rights, data tempering, and data integrity. Mainly, these techniques ensure original data recovery from watermarked data, whereas irreversible watermarking schemes only protect ownership rights. This characteristic of reversible watermarking has emerged as a candidate solution for the protection of ownership rights of data, intolerable to modifications such as medical data, genetic data, credit card, and bank account data. The main objective of this paper is to make an extensive survey of the state‐of‐the‐art in reversible watermarking techniques for relational databases to reflect recent research progress and to point out the key issues for future research. In order to analyze these techniques, a classification has been performed on the basis of (i) the extent of modifications introduced by the watermarking scheme in the underlying data and (ii) the robustness of the embedded watermark against malicious attacks. Copyright © 2015 John Wiley & Sons, Ltd.

Fragile audio watermarking with perfect restoration capacity based on an adapted integer transform

We propose a novel audio watermarking scheme which can recover the original audio carrier perfectly if the watermarked audio is modified. Besides, we can adjust the maximum tampered rate allowed and the quality of watermarked audio flexibly as required. In the scheme, an efficient generalized integer transform is improved to embed watermark data which are composed of least significant bits(LSBs) of averages in each patch, reference-bits and check-bits. LSBs are needed in the inverse transform. Then, by comparing the extracted check-bits and calculated ones, the modified area can be localized. Finally, reliable reference-bits and samples data help us reconstruct the original audio without errors. The efficiency of the proposed method is theoretically and experimentally verified.

Blind SVD-based audio watermarking using entropy and log-polar transformation

This paper proposes a blind singular value decomposition (SVD) based audio watermarking scheme using entropy and log-polar transformation (LPT) for copyright protection of audio signal. In our proposed scheme, initially the original audio is segmented into non-overlapping frames and discrete cosine transform (DCT) is applied to each frame. Low frequency DCT coefficients are divided into sub band and entropy of each sub band is calculated. Watermark data is embedded into the Cartesian components of the largest singular value obtained from the DCT sub band with highest entropy value of each frame by quantization. Simulation results indicate that the hidden watermark data is robust against different attacks. The comparison analysis shows that the proposed scheme has high data payload and provides superior performance compared to the state-of-the-art watermarking schemes reported recently.

A novel robust scaling image watermarking scheme based on Gaussian Mixture Model

In this paper, we propose a novel scaling watermarking scheme in which the watermark is embedded in the low-frequency wavelet coefficients to achieve improved robustness. We demonstrate that these coefficients have significantly non-Gaussian statistics that are efficiently described by Gaussian Mixture Model (GMM). By modeling the coefficients using the GMM, we calculate the distribution of watermarked noisy coefficients analytically and we design a Maximum Likelihood (ML) watermark detector using channel side information. Also, we extend the proposed watermarking scheme to a blind version. Consequently, since the efficiency of the proposed method is dependent on the good selection of the scaling factor, we propose L-curve method to find the tradeoff between the imperceptibility and robustness of the watermarked data. Experimental results demonstrate the high efficiency of the proposed scheme and the performance improvement in utilizing the new strategy in comparison with the some recently proposed techniques.

Information hiding with maximum likelihood detector for correlated signals

In this paper, a new scaling based information hiding approach with high robustness against noise and gain attack is presented. The host signal is assumed to be stationary Gaussian with first-order autoregressive model. For data embedding, the host signal is divided into two parts, and just one patch is manipulated while the other one is kept unchanged for parameter estimation. A maximum likelihood (ML) decoder is proposed which uses the ratio of samples for decoding the watermarked data. Due to the decorrelating property of the proposed decoder, it is very efficient for watermarking highly correlated signals for which the decoding process is not straightforward. By calculating the distribution of the decision variable, the performance of the decoder is analytically studied. To verify the validity of the proposed algorithm, it is applied to artificial Gaussian autoregressive signals. Simulation results for highly correlated host signals confirm the robustness of our decoder.

Security Method for Multimedia Content by Using Watermarking

Digital watermarking is a technique developed to help copyright protection of Image, audio & video files. It has been spurred by the growth of the Internet, and the ease of copying. This has led to an unprecedented numbers in copyright infringements. The digital audio & video watermarking is concerned with embedding data in a signal the watermark data can be accurately detected. Watermarking algorithm based on Empirical Mode Decomposition (EMD) is introduced. The signal is divided into frames and each one is decomposed adaptively by Empirical Mode Decomposition into intrinsic oscillatory components. The data embedding rate of EMD algorithm is 46.9-50.3 b/s; the robustness of hidden watermark is identified using Mp3 compression, additive noise, and quantization, cropping, filtering and resampling.

Ontology-guided distortion control for robust-lossless database watermarking: application to inpatient hospital stay records.

In this paper, we propose a new semantic distortion control method for database watermarking. It is based on the identification of the semantic links that exist in-between attribute's values in tuples by means of an ontology. Such a database distortion control provides the capability for any watermarking scheme to avoid incoherent records and consequently ensures: i) the normal interpretation of watermarked data, i.e. introducing a watermark semantically imperceptible; ii) prevent the identification by an attacker of watermarked tuples. The solution we present herein successfully combines this semantic distortion control method with a robust lossless watermarking scheme. Experimental results conducted on a medical database of more than one half million of inpatient hospital stay records also show a non-negligible gain of performance in terms of robustness and database distortion.

Improved integral imaging based image copyright protection algorithm using 3-D computational integral imaging pickup and super-resolution reconstruction technique

Cellular automata transform (CAT) based watermarking method can provide multi-transform planes for embedding watermark. In this paper, to overcome conventional transform-based watermarking methods have only one transform plane for watermark embedding, we propose a CAT-based watermarking system, in which the three-dimensional (3-D) watermark data is decomposed by the computational integral imaging (CII) technique and be embedded into the CAT domain. However, in the 3-D watermark reconstruction process, the computational integral imaging reconstruction (CIIR) technique in CII system that can degrade the quality of the extracted watermark due to the pixel overlapping. We introduce the super-resolution reconstruction technique that can effectively improve this problem. Some experiments are carried out to verify the performance of the CAT-based watermarking scheme. From the experimental results, the proposed watermarking system can provide good imperceptibility and high robustness.

영상의 시점변화와 악의적 공격에 대한 디지털 워터마킹

This paper deals with digital watermarking methods to protect ownership of image with targeting the ultra-high multi-view or free-view image service in which an arbitrary viewpoint image should be rendered at the user side. The main purpose of it is not to propose a superior method to the previous methods but to show how difficult to construct a watermarking scheme to overcome the viewpoint translation attack. Therefore we target the images with various attacks including viewpoint translation. This paper first shows how high the error rate of the extracted watermark data from viewpoint-translated image by basic schemes of the method using 2DDCT(2D discrete cosine transform) and the one using 2DDWT(2D discrete wavelet transform), which are for 2D image. Because the difficulty in watermarking for the viewpoint-translated image comes from the fact that we don`t know the translated viewpoint, we propose a scheme to find the translated viewpoint, which uses the image and the corresponding depth information at the original viewpoint. This method is used to construct the two non-blind watermarking methods to be proposed. They are used to show that recovery of the viewpoint affect a great deal of the error rate of the extracted watermark. Also by comparing the performances of the proposed methods and the previous ones, we show that the proposed ones are better in invisibility and robustness, even if they are non-blind.

Hiding patients confidential datainthe ECG signal viaa transform-domain quantization scheme.

Watermarking is the most widely used technology in the field of copyright and biological information protection. In this paper, we use quantization based digital watermark encryption technology on the Electrocardiogram (ECG) to protect patient rights and information. Three transform domains, DWT, DCT, and DFT are adopted to implement the quantization based watermarking technique. Although the watermark embedding process is not invertible, the change of the PQRST complexes and amplitude of the ECG signal is very small and so the watermarked data can meet the requirements of physiological diagnostics. In addition, the hidden information can be extracted without knowledge of the original ECG data. In other words, the proposed watermarking scheme is blind. Experimental results verify the efficiency of the proposed scheme.