Search

Color image watermarking has achieved great success in various applications such as copy protection, content authentication, tamper detection and recovery, etc. The present paper provides a detailed overview of watermarking along with its characteristics, evaluation metrics, and current applications. We then provide a comprehensive survey of different approaches along with their merits and limitations. Furthermore, we summarize each of the approaches in detail, including objectives, goals, embedding location, evaluation metrics, and weaknesses, and discuss recent challenges and their possible solutions. We believe this paper will provide readers with comprehensive insight into the field of watermarking research.

With the rapidly rising interest in geographic information system (GIS) contents, a large volume of valuable map data has been unlawfully distributed by pirates. Therefore, the secure storage and transmission of classified national digital map datasets have been increasingly threatened. As the importance of secure, large-volume map datasets has increased, vector map security techniques that focus on secure network and data encryption have been studied. These techniques are required to ensure access control and prevent illegal copying of digital maps. This paper presents perceptual encryption on the vector compression domain for copy protection and access control of vector maps. Our algorithm compresses all vector data of polylines and polygons by lossless minimum coding object (MCO) units and perceptually encrypts using two processes using the mean points and directions of MCOs. The first process changes the position of vector data by randomly permuting the mean points of MCOs, the so-called position encryption. The second process changes the geographic shape by circularly encrypting the directions of vertices in MCOs by the XOR operator. Experimental results have verified that our algorithm can encrypt GIS digital maps effectively and simply and can also improve the compression ratio, unlike general data encryption techniques, and thus, our algorithm is very effective for a large volume of GIS datasets. We design a lossy/lossless compression and perceptual encryption algorithm for vector map.Our algorithm ensures access control and copyright protection of vector map.Each object is performed independently for random access about specified location.All objects are compressed as a unit of minimum coding object (MCO) units.All objects are perceptually encrypted using mean points and directions of MCO.

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.

The purpose of this paper is to investigate how different types of strategic interaction affect firms’ optimal levels of digital rights management (DRM). In our game-theoretical duopoly model, the firms do not directly compete with prices, but they become interdependent while coping with digital piracy. Our analysis shows that (1) stricter public copy protection by the government leads to lower DRM levels and more piracy when the firms regard their DRM levels as ‘‘strategic substitutes,” but to higher DRM levels and less piracy when the firms perceive their DRM levels as ‘‘strategic complements,” and (2) a higher degree of similarity between the DRM systems leads to lower DRM levels and more piracy. We also discuss the policy implications of these findings.

We present methods to efficiently analyze scalable, compressed H.264/scalable video coding (SVC) video streams. Relying solely on information present in the compressed stream, we estimate the global camera motion, perform motion segmentation and use a simple matching process to track moving objects over time. Object energy images are constructed in order to help resolve the problem of object correspondence during the occlusions of multiple objects. To save computing time, we analyze lower spatial layers of the stream and add higher layer information only if necessary. We draw 2-D object trajectories in the view plane of the camera and use the temporal evolution of the objects' properties to estimate the relative distance to the camera, resulting in a pseudo 3-D representation of the trajectories. Finally, the suitability of the motion parameters to perform video retrieval/copy detection tasks is demonstrated. We therefore form two simple descriptors that are invariant to a series of transformations.

In this paper, we present Waveprint, a novel method for audio identification. Waveprint uses a combination of computer-vision techniques and large-scale data-stream processing algorithms to create compact fingerprints of audio data that can be efficiently matched. The resulting system has excellent identification capabilities for small snippets of audio that have been degraded in a variety of manners, including competing noise, poor recording quality and cell-phone playback. We explicitly measure the tradeoffs between performance, memory usage, and computation through extensive experimentation. The system is more efficient in terms of memory usage and computation, while being more accurate when compared with previous state of the art systems. The applications of Waveprint include song identification for end-consumer use, copyright protection for audio assets, copyright protection for television assets and synchronization of off-line audio sources, such as live television.

With the increasing demands of copyright protection, watermarking technology has being paid more and more attention. In the design of a watermarking algorithm, a good watermark detection scheme can improve the detection rate, which pushes an increasing number of researchers to work with optimum detectors. In this paper, we propose a locally optimum using a locally most powerful test with respect to Barni's multiplicative water marking which is based on the human visual system (HVS). In the proposed detection scheme, the probability density function of DWT coefficients is modeled using the generalized Gaussian distribution, and the decision threshold is obtained by the Neyman-Pearson (NP) criterion. Additionally, we prove that the existing correlation detection is a special case of the proposed locally optimum detection, and we provide an improved correlation threshold under the condition of locally optimum detection.

In this paper, a novel asymmetric public-key watermarking scheme for static images is proposed. The watermark is embedded with the use of a private key, while the decoding uses only a simple public key. The asymmetric watermark carries certain number of bits of information. However, neither the knowledge of the public key, nor the knowledge of the hidden information, allows the attacker to remove the watermark. That information can be read from an attacked image, in particular from a geometrically transformed image. Moreover, the proposed watermark could be used as a synchronization template for another private-key watermark.

Digital watermarking is a helpful technology for providing copyright protection for valuable multimedia data. In particular, video watermarking deals with several issues, which are unique to various types of media watermarking. In this paper, these issues, including compressed domain watermarking, real-time detection, bit-rate control, and resistance to watermark estimation attacks, will be addressed. Since video sequences are usually compressed before they are transmitted over networks, we first describe how watermark signals can be embedded into compressed video while keeping the desired bit-rate nearly unchanged. In the embedding process, our algorithm is designed to operate directly in the variable length codeword (VLC) domain to satisfy the requirement of real-time detection. We describe how suitable positions in the VLC domain can be selected for embedding transparent watermarks. Second, in addition to typical attacks, the peculiar attacks that video sequences encounter are investigated. In particular, in order to deal with both collusion and copy attacks that are fatal to video watermarking, the video frame-dependent watermark (VFDW) is presented. Extensive experimental results verify the excellent performance of the proposed compressed video watermarking system in addressing the aforementioned issues.

In digital watermarking, robustness is still a challenging problem if different sets of attacks need to be tolerated simultaneously. In this paper, we deal with this problem by using an integrated solution involving side-informed embedding, moment normalization, and content-dependent watermarks. First, a new image watermarking method based on the concept of communications with side information is proposed. We investigate the characteristics of mean filtering in formulating new watermark embedding and extraction processes. Second, regarding resistance to geometrical attacks, we do not rely on the concept of pilot signals because they are vulnerable to synchronization removal attacks. We instead use block-based watermarking and moment normalization mechanisms to recover geometrical distortions. Third, regarding resistance to the copy attack, the content-dependent watermark is employed to avoid treating an un-watermarked image as one that has been watermarked. The robustness of our approach has been verified using both the StirMark and the copy attack.

Digital watermarking has been widely applied to solve copyright protection problems of digital media relating to illegal use or distribution. In the past few years, several gray-level image watermarking schemes have been proposed, but their application to color image watermarking schemes is scarce and usually works on the luminance or individual color channel. In this paper, a new color image watermarking scheme based on the color quantization technique is proposed. Experimental results are shown to demonstrate the validity of the proposed scheme. Furthermore, the proposed scheme can be applied to other multimedia applications that are based on the color quantization technique.

This paper examines the publisher's optimal copy-protection policies. Even if copying is more cost-efficient than producing an original, private copying harms the publisher for two reasons. First, the copy users’ contribution to the original's price is too small, and second, there is a time lag between providing the original and distributing copies. If and only if both production costs of copies and institutional costs of the distribution of copies are sufficiently small; does controlling the number of copies benefit the publisher. However, the publisher's optimal number of copies is too low from a social welfare perspective.

We discuss wavelet filter parametrization as a means to add security to wavelet-based watermarking schemes. It turns out that our proposed scheme is resistant to unauthorized detection and unauthorized removal attacks and is equally robust as compared to the use of standard wavelet filters in case the underlying watermarking scheme is spread-spectrum based. Quantization-based watermarking techniques are not suited to be enhanced by this approach. We assess the security, quality and robustness of our approach in the light of four selected watermarking algorithms. Furthermore, we present an attack tailored to exploit a common weakness in image-adaptive watermarking and propose filter parametrization as a suitable countermeasure.

Digital watermarking was introduced at the end of the 20th century to provide means of enforcing copyright protection once the use and distribution of digital multimedia data have exploded. This technology has first been intensively investigated for still images and recent efforts have been put to exhibit unifying characteristics. On the other hand, the situation is rather different in the context of video watermarking, where unrelated articles are scattered throughout the literature. The purpose of this paper is consequently to give an in-depth overview of video watermarking and to point out that it is not only a simple extension of still images watermarking. New applications have to be considered, specific challenges have to be taken up and video-driven approaches have to be investigated.

This paper proposes a novel method to detect copied versions of digital images. The proposed copy detection scheme can be used as either an alternative approach or a complementary approach to watermarking. A test image is reduced to an 8×8 sub-image by intensity averaging, and the AC coefficients of its discrete cosine transform (DCT) are used to compute distance from those generated from the query image, of which a user wants to find copies. A challenge is that the replicated image may be processed to elude copy detection or enhance image quality. We show ordinal measure of DCT coefficients, which is based on relative ordering of AC magnitude values and using distance metrics between two rank permutations, is robust to various modifications of the original image. The optimal threshold selection scheme using the maximum a posteriori criterion is also described. The efficacy of the proposed method is extensively tested with both cluster-free and cluster-based detection scheme.

In the paper we discuss how one could solve the second problem of digital watermarking. It has been presented a solution to copy protection of multimedia objects and dozens of schemes and algorithms have been proposed. Two main problems seriously darken the future of this technology though. The large number of attacks and weaknesses which appear as fast as new algorithms are proposed emphasizes the limits ofthis technology and in particular the fact that it may not match users' expectations. Requirements, tools and methodologies to assess the current technologies are almost non-existent. The lack of benchmarking ofcurrent algorithms is blatant. This confuses rights holders as well as software and hardware manufacturers and prevents them from using the solution appropriate to their needs. Indeed basing long-lived prQtection schemes on badly tested watermarking technology does not make sense

The music and software industry are employing copy-protection devices in CDs and digital downloads to strengthen their weak appropriability regimes that leave ample opportunities for modern-day piracy. The effectiveness of the strategy is explained on the grounds that (a) the knowledge involved in copy protection is generally too sophisticated for consumers to circumvent, and (b) consumers are not allowed to use circumvention techniques created by knowledgeable third parties. Copy protection is controversial, because it deprives consumers of making home copies of music and software, and hence overrules copyright law that exempts the copying for private use. It is argued that the technical enforcement of copyright protection in the home domain of millions of individuals necessitates a wide consensus between business and society about the legitimacy of private and fair use.

Advances in digital technology have provided rights holders with the opportunity to develop new ways of formatting and distributing works but also allow unauthorized reproduction on an unprecedented scale. The digital age has made copying by private individuals easier, posing an increasing threat to the interests of rights holders. Whilst the law has developed to counter unlawful copying one suggestion is that technology itself can provide the solution: the often quoted phrase “the answer to the machine is in the machine”. There is no doubt that there has been a proliferation of copy protection devices and measures. Recent cases demonstrate that an effective legal framework is required to complement copy protection measures and stem the growth of unauthorized copying.

It is well known that a digital signature scheme and digital timestamp are two well-defined security methods for copyright protection. However, these techniques are not suitable for directly dealing with digital images. For this reason, digital watermarking has received considerable attention for copyright protection. Unfortunately, there are still some challenges in the proposed watermarking schemes. Here, we will introduce cryptographic tools into watermarking, in such a way that both the advantages of cryptographic tools and digital watermarking are available. The publicly verifiable property and tolerant distortion property are therefore possible. Based on this idea, a lossless and robust copyright-protection scheme, distinct from conventional watermarking techniques, is proposed. Our scheme is strong enough to resist common image processing, geometric distortions and some intentional attacks. Some of the attacks are still challenges for the proposed watermarking methods. A series of experiments are conducted to prove the robustness property. The StirMark and unZign attacks are adopted as benchmark verification.

A great number of digital watermarking approaches do exist, but it seems that transform domain watermarking dominates the field. The detection of such schemes is based on thresholds extracted by statistic rules on which the method relies. In this work, we propose an improved detector for such techniques. It extends the traditional schemes by taking into account the similarity diagrams that are widely used until now as an evidence of the watermarks existence and uniqueness.

The paper deals with the statistical analysis of the behaviour of a blind copyright protection watermarking system based on chaotic watermark signals generated by n-way Bernoulli shift maps. The analysis involves theoretical evaluation of the system detection reliability, when a correlator detector is used. The effect of distortions (lowpass filtering, noise corruption of the watermarked data) on the detection reliability is also theoretically investigated. The system is modelled in a communication framework considering the signal as interference and converting the addressed problem to the detection of the underlying watermark signal. The aim of the paper is two-fold: (i) to introduce the n-way Bernoulli shift generated chaotic watermarks and theoretically contemplate their properties with respect to the detection reliability and (ii) to theoretically establish their potential superiority against the widely used (pseudo-)random watermarks. An important property of Bernoulli watermarks is their controllable spectral/correlation properties that renders them ideal for a variety of applications. Bernoulli watermarks can be generated with lowpass spectral properties to withstand lowpass attacks. When no distortions are to be inflicted, white spectrum Bernoulli watermarks can be generated so that their performance converges to that of the random watermarks. Experimental verification of the theoretical analysis results has been performed as well.

A digital home network is a cluster of digital audio/visual (A/V) devices including set-top boxes, TVs, VCRs, DVD players, and general-purpose computing devices such as personal computers. The network may receive copyrighted digital multimedia content from a number of sources. This content maybe broadcast via satellite or terrestrial systems, transmitted bycable operators, or made available as prepackaged media (e.g., a digital tape or a digital video disc). Before releasing their content for distribution, the content owners mayrequire protection byspecifying access conditions. Once the content is delivered to the consumer, it moves across the home network until it reaches its destination where it is stored or displayed. A copy protection system is needed to prevent unauthorized access to bit streams in transmission from one A/V device to another or while it is in storage on magnetic or optical media. Recently, two fundamental groups of technologies, encryption and watermarking, have been identi"ed for protecting copyrighted digital multimedia content. This paper is an overview of the work done for protecting content owners' investment in intellectual property. 2001 Elsevier Science B.V. All rights reserved.

Digital rights management technology is designed to prevent piracy and facilitate the creation of innovative business models around digital content. Its technological limitations may be surpassed only by its economic ones.

Digital mass recording devices for video data will enter the consumer market soon. Service providers are reluctant to offer services in digital form because of their fears for unrestricted duplication and dissemination. Therefore adequate copy protection systems should be developed, most likely based on labeling techniques. In this paper we propose two different techniques for the real-time labeling of digital video. Both methods embed the label information directly into an MPEG compressed video bitstream. The first method embeds the label by changing variable length codes in the bitstream. The second method discards some of the high frequency DCT-coefficients of the bitstream to embed the label. The first technique is computationally less expensive than the second one, however, the second one is more robust against attacks to remove the label. We show that the label can still be extracted after MPEG re-encoding at a lower bit-rate.

This study finds that the most profitable short-term, add-on Terminal Emulator (TE) products are Data-Stream-To-Disk, Multi-Session, and Net-Work Printer capabilities. In the longer term, as fixed costs become avoidable, the same products remain the most profitable, only their rank changes. In the long term Multi-Session is the first, Net-Work Printer is second, and Data-Stream-To-Disk is the last. The selection of appropriate features for TE products can be very difficult for both manufacturers, as well as for end-users. This study describes an interactive microcomputer based Feature Selection System (FSS). The Feature Price Contribution Margin (FPCM) measures to what degree a specific feature meets end-user needs, and measures how profitable they are for the developer and the manufacturer FSS produces a segmented income statement of possible future product lines. It also compares the outcome of integrating and bundling a feature into a product, versus marketing this feature as a separate “add-on” product line to a TE. In such context, it could also be used for litigation support to quantify the damages that result from the absence of a feature to either the vendor or the end-user.

The purpose of this paper is to investigate how different types of strategic interactions between two firms affect their optimal pricing and private copy protection levels of digital products. In our model, the firms do not directly interact with each other in terms of prices, but they become interdependent through private copy protection levels. Our analysis shows that 1) stronger public copy protection leads to lower private copy protection and more piracy when the firms regard their private copy protection levels as "strategic substitutes," but higher private copy protection and less piracy when they treat their private copy protection levels as "strategic complements" and 2) more compatibility between private copy protection systems leads to lower private copy protection and more piracy. We also discuss public policy issues regarding these findings.