A dual watermark-fingerprint system

This article proposes a multimedia content protection system in which all copies of a protected object are identically watermarked, but each user has a distinct secret detection key that differs from the secret embedding key. An attacker with access to one detection key can fool the corresponding watermark detector but not other watermark detectors. Surprisingly, analogous to a criminal action, during this attack the attacker necessarily inserts his or her fingerprint into the modified content. Even a collusion clique of relatively large size cannot entirely remove the secret marks from the protected content by colluding their detection keys. More importantly, if the clique is not large enough, traces of the detection keys of all colluders can be detected with relatively high accuracy in the attacked clip. Our proposed watermark-fingerprint system achieves a minimum collusion size K that grows linearly with the size N of the marked object. In addition, we can augment our watermark-fingerprint system with a segmentation layer. The media content is partitioned into 5 segments, in which media players as well as forensic analyzers can reliably detect a watermark or fingerprint. Only detection keys that belong to the same segment can participate in the collusion clique. With segmentation, the minimum collusion size K grows as 0(N log N). Therefore, with or without segmentation, our watermark-fingerprint system significantly improves on the best-known asymptotic resistance to (fingerprint) collusion attacks of about O(N/sup 1/4/). Because we use a new protection protocol, comparing our system to classic fingerprint systems might seem unfair. However, such a comparison is important because the two technologies share a common goal: multimedia copyright enforcement. Our aim in this article is to characterize the collusion attacks against this system under the assumption that watermark detection is robust against signal-processing attacks on the protected object.     

Blind pattern matching attack on watermarking systems

Billions of dollars allegedly lost to piracy of multimedia content have triggered the industry to rethink the way music and films are distributed on the Internet. As encryption is vulnerable to digital or analog re-recording, currently almost all copyright protection mechanisms rely to a certain extent on watermarking. A watermark is an imperceptive secret hidden into a host signal. We analyze the security of multimedia copyright protection systems that use watermarks by proposing a new breed of attacks on generic watermarking systems. A typical blind pattern matching attack relies on the observation that multimedia content is often highly repetitive. Thus, the attack procedure identifies subsets of signal blocks that are similar and permutes these blocks. Assuming the permuted blocks are marked with distinct secrets, it can be shown that any watermark detector is facing a task of exponential complexity to reverse the permutations as a preprocessing step for watermark detection. We describe the logistics of the attack and an implementation against a spread-spectrum and a quantization index modulation data hiding technology for audio signals.     

Cut-based functional debugging for programmable systems-on-chip

Due to the growth of both design complexity and the number of gates per pin, functional debugging has emerged as a critical step in the development of a system-on-chip (SOC). Traditional approaches, such as system emulation and simulation, are becoming increasingly inadequate to address the system debugging needs. Design simulation is two to ten orders of magnitude slower than emulation and, thus, is used primarily for short, focused test sequences. Emulation has the required speed but imposes strict limitations on signal observability and controllability. We introduce a new debugging approach for programmable SOC's that leverages the complementary advantages of emulation and simulation. We propose a set of tools, transparent to both the design and debugging process, that enables the user to run long test sequences in emulation and, upon error detection, roll back to an arbitrary instance in execution time and switch over to simulation-based debugging for full design visibility and controllability. The efficacy of the developed approach is dependent upon the method for transferring the computation from one execution domain to another. Although the approach can be applied to any computational model, we have developed a suite of optimization techniques that enable computation transfer in a mixed synchronous data flow semi-infinite stream random-access machine computation model. This computation model is frequently used in many communications and multimedia SOCs. The effectiveness of the developed debugging methodology has been demonstrated on a set of multicore designs where combined emulation-simulation has been enabled with low hardware and performance overhead     

High-Fidelity Data Embedding for Image Annotation

High fidelity is a demanding requirement for data hiding, especially for images with artistic or medical value. This correspondence proposes a high-fidelity image watermarking for annotation with robustness to moderate distortion. To achieve the high fidelity of the embedded image, we introduce a visual perception model that aims at quantifying the local tolerance to noise for arbitrary imagery. Based on this model, we embed two kinds of watermarks: a pilot watermark that indicates the existence of the watermark and an information watermark that conveys a payload of several dozen bits. The objective is to embed 32 bits of metadata into a single image in such a way that it is robust to JPEG compression and cropping. We demonstrate the effectiveness of the visual model and the application of the proposed annotation technology using a database of challenging photographic and medical images that contain a large amount of smooth regions.     

Regulation of protein synthesis in mammary glands of lactating dairy cows by starch and amino acids

The objective of this study was to evaluate local molecular adaptations proposed to regulate protein synthesis in the mammary glands. It was hypothesized that AA and energy-yielding substrates independently regulate AA metabolism and protein synthesis in mammary glands by a combination of systemic and local mechanisms. Six primiparous mid-lactation Holstein cows with ruminal cannulas were randomly assigned to 4 treatment sequences in a replicated incomplete 4 × 4 Latin square design experiment. Treatments were abomasal infusions of casein and starch in a 2 × 2 factorial arrangement. All animals received the same basal diet (17.6% crude protein and 6.61 MJ of net energy for lactation/kg of DM) throughout the study. Cows were restricted to 70% of ad libitum intake and abomasally infused for 36 h with water, casein (0.86 kg/d), starch (2 kg/d), or a combination (2 kg/d starch + 0.86 kg/d casein) using peristaltic pumps. Milk yields and composition were assessed throughout the study. Arterial and venous plasma samples were collected every 20 min during the last 8 h of infusion to assess mammary uptake. Mammary biopsy samples were collected at the end of each infusion and assessed for the phosphorylation state of selected intracellular signaling molecules that regulate protein synthesis. Animals infused with casein had increased arterial concentrations of AA, increased mammary extraction of AA from plasma, either no change or a trend for reduced mammary AA clearance rates, and no change in milk protein yield. Animals infused with starch had increased milk and milk protein yields, increased mammary plasma flow, reduced arterial concentrations of AA, and increased mammary clearance rates and net uptake of some AA. Infusions of starch increased plasma concentrations of glucose, insulin, and insulin-like growth factor-I. Starch infusions increased phosphorylation of ribosomal protein S6 and endothelial nitric oxide synthase, consistent with changes in milk protein yields and plasma flow, respectively. Phosphorylation of the mammalian target of rapamycin was increased in response to starch only when casein was also infused. Thus, cell signaling molecules involved in the regulation of protein synthesis differentially responded to these nutritional stimuli. The hypothesized independent effects of casein and starch on animal metabolism and cell signaling were not observed, presumably because of the lack of a milk protein response to infused casein.     

Spread-spectrum watermarking of audio signals

Watermarking has become a technology of choice for a broad range of multimedia copyright protection applications. Watermarks have also been used to embed format-independent metadata in audio/video signals in a way that is robust to common editing. In this paper, we present several novel mechanisms for effective encoding and detection of direct-sequence spread-spectrum watermarks in audio signals. The developed techniques aim at (i) improving detection convergence and robustness, (ii) improving watermark imperceptiveness, (iii) preventing desynchronization attacks, (iv) alleviating estimation/removal attacks, and finally, (v) establishing covert communication over a public audio channel. We explore the security implications of the developed mechanisms and review watermark robustness on a benchmark suite that includes a combination of audio processing primitives including: time- and frequency-scaling with wow-and-flutter, additive and multiplicative noise, resampling, requantization, noise reduction, and filtering.     

EyeCerts

In this paper, we propose EyeCerts, a biometric system for the identification of people which achieves offline verification of certified, cryptographically secure documents. An EyeCert is a printed document which certifies the association of content on the document with a biometric feature-a compressed version of a human iris in this work. The system is highly cost-effective since it does not require high complexity, hard-to-replicate printing technologies. Further, the device used to verify an EyeCert is inexpensive, estimated to have approximately the same cost as an off-the-shelf iris-scanning camera. As a central component of the EyeCert system, we present an iris analysis technique that aims to extract and compress the unique features of a given iris with a discrimination criterion using limited storage. The compressed features should be at maximal distance with respect to a reference iris image database. The iris analysis algorithm performs several steps in three main phases: 1) the algorithm detects the human iris by using a new model which is able to compensate for the noise introduced by the surrounding eyelashes and eyelids, 2) it converts the isolated iris using a modified Fourier-Mellin transform into a standard domain where the common radial patterns of the human iris are concisely represented, and 3) it optimally selects, aligns, and near-optimally compresses the most distinctive transform coefficients for each individual user. Using a low-quality imaging system (sub-U.S.$100), a /spl chi//sup 2/ error distribution model, and assuming a fixed false negatives rate of 5%, EyeCert caused false positives at rates better than 10/sup -5/ and as low as 10/sup -30/ for certain users.     

The Replacement Attack

Billions of dollars allegedly lost to piracy of multimedia have recently triggered the industry to rethink the way music and movies are distributed. As encryption is vulnerable to rerecording, currently all copyright protection mechanisms tend to rely on watermarking. A watermark is an imperceptive secret hidden in a host signal. In this paper, we analyze the security of multimedia copyright protection systems that use watermarks by proposing a new breed of attacks on generic watermarking systems. A typical replacement attack relies upon the observation that multimedia content is often highly repetitive. Thus, the attack procedure replaces each signal block with another, perceptually similar block computed as a combination of other similar blocks found either within the same media clip or within a library of media clips. Assuming the blocks used to compute the replacement are marked with distinct secrets, we show that if the computed replacement block is at some minimal distance from the original marked block, a large portion of the embedded watermark is removed. We describe the logistics of the attack and an exemplary implementation against a spread-spectrum data hiding technology for audio signals.     

Procedure Based Program Compression

Cost and power consumption are two of the most important design factors for many embedded systems, particularly consumer devices. Products such as Personal Digital Assistants, pagers with integrated data services, and smart phones have fixed performance requirements but unlimited appetites for reduced cost and increased battery life. Program compression is one technique that can be used to attack both of these problems. Compressed programs require less memory, thus reducing the cost of both direct materials and manufacturing. Furthermore, by relying on compressed memory, the total number of memory references is reduced. This reduction saves power by lowering the traffic on high capacitance buses. This paper will discuss a new approach to implementing transparent program compression that requires little or no hardware support. Procedures are compressed individually, and a directory structure is used to bind them together at runtime. Decompressed procedures are explicitly cached in ordinary RAM as complete units, thus resolving references within each procedure. This approach has been evaluated on a set of 25 embedded multimedia and communications applications, and results in an average memory reduction of 40% with a runtime performance overhead of 10%.     

Digital rights management for digital cinema

There is a wide consensus among feature film production studios that the Internet era brings a new paradigm for film distribution to cinemas worldwide. The benefits of digital cinema to both producers and cinemas are numerous: significantly lower distribution and maintenance costs, immediate access to film libraries, higher presentation quality, and strong potential for developing new business models. Despite these advantages, the studios are still reluctant to jump into the digital age. An important concern regarding digital and conventional cinema is the danger of widespread piracy. Piracy already costs Hollywood an estimated two billion dollars annually, and digital cinema without proper copyright enforcement could increase this number. In this paper, we present a copyright management system that aims at providing the set of necessary security tools: standard cryptographic primitives and copyright protection mechanisms that enable a reliable and secure feature film delivery system.