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Digital watermarking technology would be very useful as part of a related service introduction system (RSIS); which links physical objects in the real world, such as printed photographs, to those in the cyber world. In this paper, we focus on a camera-equipped mobile phone as an RSIS terminal, and propose a fast watermark detection scheme for the captured images. The proposed scheme consists of two processes; to correct geometric distortion of the captured image, and to detect watermark information from the corrected image. For our scheme, we also propose a fast quadrangle detection algorithm and a robust watermarking algorithm. Moreover, we introduce a quantitative evaluation method for determining the reliability of watermark detection, which is essential for RSIS services. Finally, we show that the proposed scheme enables users to detect embedded information far less than one second, even when implemented as a Java application on a mobile phone with limited resources, and our experiments confirm the efficiency of our scheme.

Evaluating and benchmarking software and hardware field programmable gate array (FPGA)-based digital watermarking are considered challenging tasks because of multiple and conflicting evaluation criteria. A few evaluation and benchmarking techniques/frameworks have been implemented to digital watermarking or steganography; however, these approaches still present certain limitations. In particular, fixing some attributes on account of other attributes and well-known benchmarking approaches are limited to robust watermarking techniques. Thus, this study aims toward a new methodology for evaluation and benchmarking using multi-criteria analysis for software and hardware “FPGA”-based digital watermarking or steganography. To achieve this objective, two iterations are conducted. The first iteration consists of two stages: discussing software and hardware “FPGA”-based digital watermarking or steganography to create a dataset with various samples for benchmarking and discussing the evaluation method and then discussing the test for software and hardware “FPGA”-based digital watermarking or steganography according to multi-criteria evaluation (i.e., complexity, payload and quality) to create a decision matrix. The second iteration applies different decision-making techniques (i.e., SAW, MEW, HAW, TOPSIS, WSM and WPM)) to benchmark the results of the first iteration (i.e., software or hardware FPGA-based digital watermarking or steganography approaches). Then, the discussed mean, standard deviation and paired sample $t$-test results are used to measure the correlations among different techniques based on the ranking results. The discussion findings are described as follows: (1) the integration of developer and evaluator preferences into the evaluation and benchmarking for software and hardware FPGA-based digital watermarking or steganography, (2) the process of assigning weights and (3) visualizing large-scale data sample in either software or hardware FPGA-based digital watermarking or steganography algorithms.

Digital watermark technology has been proposed as an effective method to protect the copyright of multimedia data. An adaptive image watermark scheme based on fuzzy inference system that in discrete wavelet transform domain is proposed. By exploiting the brightness and texture characteristics of human visual system and considering properties of the original image wavelet coefficient, a fuzzy inference system is designed whose inputs are parameters of brightness and texture of the original image and output is the strength of embedded watermarks. It ensures that the watermark embedding strength is determined adaptively. The experimental results show that the watermarks embed by the proposed scheme are robust against attacks commonly used image processing methods such as JPEG compression, Gaussian noise, cropping, mean filtering, median filtering, rotation, and rescaling etc. Proposed scheme are shown to provide very good results in term of image imperceptibility, too.

This paper presents a new approach based on multi-dimensional evaluation and benchmarking for data hiding techniques, i.e., watermarking and steganography. The novelty claim is the use of evaluation matrix (EM) for performance evaluation of data hiding techniques; however, one major problem with performance evaluation of data hiding techniques is to find reasonable thresholds for performance metrics and the trade-off among them in different data hiding applications. Two experiments are conducted. The first experiment included LSB techniques (eight approaches) based on different payload results and the noise gate approach; a total of nine approaches were used. Five audio samples with different audio styles are tested using each of the nine approaches and considering three evaluation criteria, namely, complexity, payload, and quality, to generate watermarked samples. The second experiment involves the use of various decision-making techniques simple additive weighting (SAW), multiplicative exponential weighting (MEW), hierarchical adaptive weighting (HAW), technique for order of preference by similarity to ideal solution (TOPSIS), weighted sum model (WSM) and weighted product method (WPM) to benchmark the results of the first experiment. Mean, standard deviation (STD), and paired sample t-test are then performed to compare the correlations among different techniques on the basis of ranking results. The findings are as follows: (1) A statistically significant difference is observed among the ranking results of each multi-criteria decision-making (MCDM) technique, (2) TOPSIS-Euclidean is the best technique to solve the benchmarking problem among digital watermarking techniques. (3) Among the decision-making techniques, WSM has the lowest rank in terms of solving the benchmarking problem. (4) Under different circumstances, the noise gate watermarking approach performs better than LSB algorithms.

In this paper, a moment estimation method of the embedding strength for the digital image watermark is discussed. Under the assumptions that watermark are a known, zero-mean, binary valued sequence and that the original image data are an i.i.d. random sequence from a Weibull distribution, embedding strength should be estimated by observing to the averages of the watermarked image, the averages of the original image, and calculating briefly between them. The approach is based on moment estimation method of the watermark embedding strength. The experimental results show that this method is effective for De Rosa et.al.’s watermark detector. Moreover, according to the addition, multiplication and fused embedding rules, we also compare and analyze their performance using PSNR. The conclusions are useful to the research in the future.

In order to enhance robustness and security of the embedded watermark, a novel digital watermark algorithm based on chaos, image iteration and wavelet transform is proposed in this paper. Firstly, we obtain a watermark carrier of original image's low-frequency smooth part by a wavelet multilevel decomposition of original image. Then, we iterate this carrier with watermark to generate a sub-image. Finally, we reconstruct the sub-image and other part images, which are decomposed by wavelet transform. By this means, an image embedded a watermark is obtained. Sensitivity to the initial condition of chaotic system ensures watermark's security, meanwhile, watermark iterated at low-frequency part of original image also guarantee watermark's robustness. At last, the simulation results have certified rationality of this scheme.

In this paper, a new watermarking algorithm based on wavelet transform for MP3 digital audio signal is proposed. By using multi-resolution of the wavelet transform, the watermark is embedded into the L-level resolution, which makes the watermark be adapted into the original audio but cannot be sensed. The experimented results demonstrate that the watermarked signal is indistinguishable from the original signal and the watermark can be successfully detected after MP3 compression and decompression. The key using in procession of the watermark sequences greatly improve the security.

This article introduces a new encrypt technique applied in radio station—using digital watermark to insert the information into common carrier in order to protect the secret information and delude the illegal interceptors. It also gives the algorithm of the insertion and detection of watermark based on the change of the discrete wavelet.

With the fast development of the E-commerce, the electronic seal has become an important means of the signature, non-counterfeit, non-interpolation, data integrality assurance, and non-repudiation of the electronic document, as well as the legality and validity assurance of the signed document. This paper proposes a safe E-seal system that is based on the digital watermark technology. This E-seal system is very practical in the fields such as E-commerce, E-politics, E-medicine, and so on.

A new approach to blind digital watermarking based on the DMWT is presented in this paper. OBSA multi-wavelets have randomicity as to selection of the prefilter. A prefilter Q can be constructed through genetic algorithm according to fitness function for different images. A grey watermark image is decomposed to bit-planes. One level DMWT is realized by using the prefilter Q and OBSA multiwavelet. The watermark bit-planes are embedded in low frequency parts. "0" or "1" of the watermark bit-planes is represented by even or odd number respectively, and vice versa. The experiment results have shown that the proposed approach has the desired properties such as invisibility, reliable detection, and robustness against cropping operation.

We propose a new wavelet-based watermarking technique. The key idea of our scheme is to combine two ideas: multiresolution representation of image and odd-even quantization embedding/extracting watermark. Because many complementary watermarks need to be hidden, the watermark image designed is image-adaptive. The meaningful and complementary watermark images was embedding into the original image (host image) by odd-even quantization modifying coefficients, which was selected form the details wavelet coefficients of the original image, if their magnitudes are larger than their corresponding Just Noticeable Difference thresholds. The tests show good robustness against best-known attacks. Further research may improve the performance by refining JND thresholds.

In this paper we propose a method of embedding a two-valued image watermark into a still gray image based on wavelet transform. The process of embedding watermark is as follows: At first we divide the original image into some small blocks and implement wavelet transform for every small block. Then we change the two-valued image watermark into 1-deminsion sequence of digital watermark and logically embed this sequence of digital watermark into those wavelet coefficients. In order to enhance the robustness of the watermark we group these small blocks into two sets and embed the same sequence of digital watermark into every set of small blocks. In the process of detecting watermark we synthesize the two sequences of detected watermark so as to get a more accurate sequence of digital watermark. At last by the correlativity of pixel in a image we obtain the final treated image watermark. The experimental results show that this method has not only better invisibility but also the better robustness. Specially it is very robust to various attacks, such as mid-value filter, mean value filter, geometric transformation and so on.

Identifying the passport is important to border control police work. Wavelet decomposition and reconstruction be used to adding and detecting the digital watermark to a color image such as picture of man or woman and then made and identified the passport. Tests showed that the method we have proposed is validity to identify the passport. It can be used to avoiding the passport forgery.

Digital watermark protocol technique can prove the origination of a digital media, such as video, audio, or still image, so it is used for copyright protection. One problem with traditional digital watermark techniques is that if an illegal copy of the media is found it is impossible to determine who distribute it. In order to solve this problem, an undeniable digital watermark protocol is proposed in this paper. In this protocol, both the seller and the buyer generate the sequence of digital watermark jointly based on zero-knowledge proof. In cases where an unauthorized copy is found, it must the buyer distribute it. Experimental results show that the proposed scheme is robust against some image processing and lossy compression.

In this paper, a new robust digital image watermarking algorithm based on wavelet is proposed. Instead of embedding watermark into a source image, this algorithm uses the source image and the watermark to generate a secret key which will be kept by a third party for copy right protection and watermark detection, and the quality of the source image is not degraded. Moreover, by dividing the wavelet coefficient bands of the source image into some sections and making use of average compare strategy, this algorithm is robust against a lot of attacks, including image compressing, Gaussian noise, blurring and cropping. Experiments in this paper illustrate its effectiveness and robustness.

With the development and widespread application of multimedia and network technologies, the protection of multimedia contentssuch as image, audio, and video becomes an urgent problem. As the powerful tool for copyright protection and authentication, digital watermark technology has gained wide attention and development. The principle of digital watermark technology is briefly introduced in this paper, and the copyright authentication scheme which applied in WWW is proposed.