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493
The first 50 years of electronic watermarking
- EURASIP J. Appl. Signal Process
"... Electronic watermarking can be traced back as far as 1954. The last 10 years has seen considerable interest in digital watermarking, due in large part to concerns about illegal piracy of copyrighted content. In this paper, we consider the following questions: Is the interest warranted? What are the ..."
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Cited by 52 (0 self)
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Electronic watermarking can be traced back as far as 1954. The last 10 years has seen considerable interest in digital watermarking, due in large part to concerns about illegal piracy of copyrighted content. In this paper, we consider the following questions: Is the interest warranted? What are the commercial applications of the technology? What scientific progress has been made in the last 10 years? What are the most exciting areas for research? And where might the next 10 years take us? In our opinion, the interest in watermarking is appropriate. However, we expect that copyright applications will be overshadowed by applications such as broadcast monitoring, authentication, and tracking content distributed within corporations. We further see a variety of applications emerging that add value to media, such as annotation and linking content to the Web. These latter applications may turn out to be the most compelling. Considerable progress has been made toward enabling these applications – perceptual modelling, security threats and countermeasures, and the development of a bag of tricks for efficient implementations. Further progress is needed in methods for handling geometric and temporal distortions. We expect other exciting developments to arise from research in informed watermarking.
Great expectations: The value of spatial diversity in wireless networks
- PROCEEDINGS OF THE IEEE
, 2004
"... In this paper, the effect of spatial diversity on the throughput and reliability of wireless networks is examined. Spatial diversity is realized through multiple independently fading transmit/receive antenna paths in single-user communication and through independently fading links in multiuser commu ..."
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Cited by 45 (8 self)
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In this paper, the effect of spatial diversity on the throughput and reliability of wireless networks is examined. Spatial diversity is realized through multiple independently fading transmit/receive antenna paths in single-user communication and through independently fading links in multiuser communication. Adopting spatial diversity as a central theme, we start by studying its information-theoretic foundations, then we illustrate its benefits across the physical (signal transmission/coding and receiver signal processing) and networking (resource allocation, routing, and applications) layers. Throughout the paper, we discuss engineering intuition and tradeoffs, emphasizing the strong interactions between the various network functionalities.
Quantization index modulation methods for digital watermarking and information embedding of multimedia. The
- Journal of VLSI Signal Processing
, 2001
"... Abstract. Copyright notification and enforcement, authentication, covert communication, and hybrid transmission applications such as digital audio broadcasting are examples of emerging multimedia applications for digital watermarking and information embedding methods, methods for embedding one signa ..."
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Cited by 42 (3 self)
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Abstract. Copyright notification and enforcement, authentication, covert communication, and hybrid transmission applications such as digital audio broadcasting are examples of emerging multimedia applications for digital watermarking and information embedding methods, methods for embedding one signal (e.g., the digital watermark) within another “host ” signal to form a third, “composite ” signal. The embedding is designed to achieve efficient trade-offs among the three conflicting goals of maximizing information-embedding rate, minimizing distortion between the host signal and composite signal, and maximizing the robustness of the embedding. We present a class of embedding methods called quantization index modulation (QIM) that achieve provably good rate-distortion-robustness performance. These methods, and low-complexity realizations of them called dither modulation, are provably better than both previously proposed linear methods of spread spectrum and nonlinear methods of low-bit(s) modulation against square-error distortion-constrained intentional attacks. We also derive information-embedding capacities for the case of a colored Gaussian host signal and additive colored Gaussian noise attacks. These results imply an information embedding capacity of about 1/3 b/s of embedded digital rate for every Hertz of host signal bandwidth and every dB drop in received host signal quality. We show that QIM methods achieve performance within 1.6 dB of capacity, and we introduce a form of postprocessing we refer to as distortion compensation that, when combined with QIM, allows capacity to be achieved.
Writing on Wet Paper
"... In this paper, we show that the communication channel known as writing in memory with defective cells [1][2] is a relevant information-theoretical model for a specific case of passive warden steganography when the sender embeds a secret message into a subset C of the cover object X without sharing ..."
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Cited by 41 (10 self)
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In this paper, we show that the communication channel known as writing in memory with defective cells [1][2] is a relevant information-theoretical model for a specific case of passive warden steganography when the sender embeds a secret message into a subset C of the cover object X without sharing C with the recipient. The set C, also called the selection channel, could be arbitrary, determined by the sender from the cover object using a deterministic, pseudo-random, or a truly random process. We call this steganography “writing on wet paper ” and realize it using a simple variable-rate random linear code that gives the sender a convenient flexibility and control over the embedding process and is thus suitable for practical implementation. The importance of the wet paper scenario for covert communication is discussed within the context of adaptive steganography and perturbed quantization steganography [3]. Heuristic arguments supported by tests using blind steganalysis [4] indicate that the wet paper steganography provides improved steganographic security and is less vulnerable to steganalytic attacks compared to existing methods with shared selection channels.
Quality-Aware Images
- IEEE TRANSACTIONS ON IMAGE PROCESSING, TO APPEAR 1
, 2004
"... We propose the concept of quality-aware image, in which certain extracted features of the original (highquality) image are embedded into the image data as invisible hidden messages. When a distorted version of such an image is received, users can decode the hidden messages and use them to provide ..."
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Cited by 38 (13 self)
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We propose the concept of quality-aware image, in which certain extracted features of the original (highquality) image are embedded into the image data as invisible hidden messages. When a distorted version of such an image is received, users can decode the hidden messages and use them to provide an objective measure of the quality of the distorted image. To demonstrate the idea, we build a practical quality-aware image encoding, decoding and quality analysis system1, which employs 1) a novel reducedreference image quality assessment algorithm based on a statistical model of natural images, and 2) a previously developed quantization watermarking-based data hiding technique in the wavelet transform domain.
Preprocessed and Postprocessed Quantization Index Modulation Methods for Digital Watermarking
, 2000
"... Quantization index modulation (QIM) methods, a class of digital watermarking and information embedding methods, achievevery efficient trade-offs among the amount of embedded information (rate), the amount of embedding-induced distortion to the host signal, and the robustness to intentional and unint ..."
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Cited by 38 (1 self)
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Quantization index modulation (QIM) methods, a class of digital watermarking and information embedding methods, achievevery efficient trade-offs among the amount of embedded information (rate), the amount of embedding-induced distortion to the host signal, and the robustness to intentional and unintentional attacks. For example, we show that against independent additive Gaussian attacks, which are good models for at least some types of uninformed and unintentional attacks, QIM methods exist that achieve the best possible rate-distortion-robustness trade-offs (i.e., capacity) asymptotically at high rates and achieve performance within a few dB of capacity at all finite rates. Furthermore, low-complexity realizations of QIM methods, such as so-called dither modulation, have also been shown to achieve favorable rate-distortion-robustness trade-offs. We further develop preprocessing and postprocessing techniques that enable QIM to fully achieve capacity, not only against Gaussian attacks but also ag...
Advances in Digital Video Content Protection
, 2005
"... The use of digital video offers immense opportunities for creators; however, the ability for anyone to make perfect copies and the ease by which those copies can be distributed also facilitate misuse, illegal copying and distribution (“piracy”), plagiarism, and misappropriation. Popular Internet sof ..."
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Cited by 37 (8 self)
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The use of digital video offers immense opportunities for creators; however, the ability for anyone to make perfect copies and the ease by which those copies can be distributed also facilitate misuse, illegal copying and distribution (“piracy”), plagiarism, and misappropriation. Popular Internet software based on a peer-to-peer architecture has been used to share copyrighted movies, music, software, and other materials. Concerned about the consequences of illegal copying and distribution on a massive scale, content owners are interested in digital rights management (DRM) systems which can protect their rights and preserve the economic value of digital video. A DRM system protects and enforces the rights associated with the use of digital content. Unfortunately, the technical challenges for securing digital content are formidable and previous approaches have not succeeded. We overview the concepts and approaches for video DRM and describe methods for providing security, including the roles of encryption and video watermarking. Current efforts and issues are described in encryption, watermarking, and key management. Lastly, we identify challenges and directions for further investigation in video DRM.
Tracing traffic through intermediate hosts that repacketize flows
- IN: PROC. IEEE INFOCOM
, 2007
"... Tracing interactive traffic that traverses stepping stones (i.e., intermediate hosts) is challenging, as the packet headers, lengths, and contents can all be changed by the stepping stones. The traffic timing has therefore been studied as a means of tracing traffic. One such technique uses traffic ..."
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Cited by 36 (2 self)
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Tracing interactive traffic that traverses stepping stones (i.e., intermediate hosts) is challenging, as the packet headers, lengths, and contents can all be changed by the stepping stones. The traffic timing has therefore been studied as a means of tracing traffic. One such technique uses traffic timing as a side channel into which a watermark, or identifying tag, can be embedded to aid with tracing. The effectiveness of such techniques is greatly reduced when repacketization of the traffic occurs at the stepping stones. Repacketization is a natural effect of many applications, including SSH, and therefore poses a serious challenge for traffic tracing. This paper presents a new method of embedding a watermark in traffic timing, for purposes of tracing the traffic in the presence of repacketization. This method uses an invariant characteristic of two traffic flows which are part of the same stepping stone chain, namely, elapsed time of the flows. The duration of each flow is sliced into short fixed-length intervals. Packet timing is adjusted to manipulate the packet count in specific intervals, for purposes of embedding the watermark. A statistical analysis of the method, with no assumptions or limitations concerning the distribution of packet times, proves the effectiveness of the method given a sufficient number of packets, despite natural and/or deliberate repacketization and perturbation of the traffic timing by an adversary. The method has been implemented and tested on a large number of synthetically-generated SSH traffic flows. The results demonstrate that 100 % detection rates and less than 1 % false positive rates are achievable under conditions of 2 seconds of maximum timing perturbation and 12 % repacketization rate, using fewer than 1000 packets.
The Parallel-Gaussian Watermarking Game
- IEEE TRANS. ON INFORMATION THEORY
, 2000
"... Rates of reliable transmission of hidden information are derived for watermarking problems involving parallel Gaussian sources, which are often used to model host images and audio signals. Constraints are imposed on the average squared-error distortion that can be introduced by the information hider ..."
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Cited by 35 (5 self)
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Rates of reliable transmission of hidden information are derived for watermarking problems involving parallel Gaussian sources, which are often used to model host images and audio signals. Constraints are imposed on the average squared-error distortion that can be introduced by the information hider and by the attacker. When distortions are measured with respect to the original host data, the optimal covert and attack channels are two banks of Gaussian test channels. The solution to the watermarking game involves an optimal allocation of distortions by the information hider and by the attacker to the different channels. A fast algorithm is given for computing the optimal solution based on duality theory. For each channel we derive analytical expressions for two asymptotic regimes: weak and strong host signals. Finally we extend these results to the class of stationary Gaussian host signals with bounded, continuous spectral density. The analysis also provides an upper bound on watermarking capacity for non-Gaussian host signals.
State Amplification
, 2008
"... We consider the problem of transmitting data at rate R over a state dependent channel p(y|x, s) with state information available at the sender and at the same time conveying the information about the channel state itself to the receiver. The amount of state information that can be learned at the re ..."
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Cited by 32 (5 self)
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We consider the problem of transmitting data at rate R over a state dependent channel p(y|x, s) with state information available at the sender and at the same time conveying the information about the channel state itself to the receiver. The amount of state information that can be learned at the receiver is captured by the mutual information I(S n; Y n) between the state sequence S n and the channel output Y n. The optimal tradeoff is characterized between the information transmission rate R and the state uncertainty reduction rate ∆, when the state information is either causally or noncausally available at the sender. In particular, when state transmission is the only goal, the maximum uncertainty reduction rate is given by ∆ ∗ = max p(x|s) I(X, S; Y). This result is closely related and in a sense dual to a recent study by Merhav and Shamai, which solves the problem of masking the state information from the receiver rather than conveying it.
