1,119 research outputs found

    Real-time registration of paper watermarks

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    The aim of this article is to outline the issues involved in the application of machine vision to the automatic extraction and registration of watermarks from continuous web paper. The correct identification and localization of watermarks are key issues in paper manufacturing. As well as requiring the position of the watermark for defect detection and classification, it is necessary to insure its position on the paper prior to the cutting process. Two paper types are discussed, with and without laid and chain lines (these lines appear as a complex periodic background to the watermark and further complicate the segmentation process). We will examine both morphological and Fourier approaches to the watermark segmentation process, concentrating specifically on those images with complex backgrounds. Finally we detail a system design suitable for real-time implementation

    Spread spectrum-based video watermarking algorithms for copyright protection

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    Merged with duplicate record 10026.1/2263 on 14.03.2017 by CS (TIS)Digital technologies know an unprecedented expansion in the last years. The consumer can now benefit from hardware and software which was considered state-of-the-art several years ago. The advantages offered by the digital technologies are major but the same digital technology opens the door for unlimited piracy. Copying an analogue VCR tape was certainly possible and relatively easy, in spite of various forms of protection, but due to the analogue environment, the subsequent copies had an inherent loss in quality. This was a natural way of limiting the multiple copying of a video material. With digital technology, this barrier disappears, being possible to make as many copies as desired, without any loss in quality whatsoever. Digital watermarking is one of the best available tools for fighting this threat. The aim of the present work was to develop a digital watermarking system compliant with the recommendations drawn by the EBU, for video broadcast monitoring. Since the watermark can be inserted in either spatial domain or transform domain, this aspect was investigated and led to the conclusion that wavelet transform is one of the best solutions available. Since watermarking is not an easy task, especially considering the robustness under various attacks several techniques were employed in order to increase the capacity/robustness of the system: spread-spectrum and modulation techniques to cast the watermark, powerful error correction to protect the mark, human visual models to insert a robust mark and to ensure its invisibility. The combination of these methods led to a major improvement, but yet the system wasn't robust to several important geometrical attacks. In order to achieve this last milestone, the system uses two distinct watermarks: a spatial domain reference watermark and the main watermark embedded in the wavelet domain. By using this reference watermark and techniques specific to image registration, the system is able to determine the parameters of the attack and revert it. Once the attack was reverted, the main watermark is recovered. The final result is a high capacity, blind DWr-based video watermarking system, robust to a wide range of attacks.BBC Research & Developmen

    Information embedding and retrieval in 3D printed objects

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    Deep learning and convolutional neural networks have become the main tools of computer vision. These techniques are good at using supervised learning to learn complex representations from data. In particular, under limited settings, the image recognition model now performs better than the human baseline. However, computer vision science aims to build machines that can see. It requires the model to be able to extract more valuable information from images and videos than recognition. Generally, it is much more challenging to apply these deep learning models from recognition to other problems in computer vision. This thesis presents end-to-end deep learning architectures for a new computer vision field: watermark retrieval from 3D printed objects. As it is a new area, there is no state-of-the-art on many challenging benchmarks. Hence, we first define the problems and introduce the traditional approach, Local Binary Pattern method, to set our baseline for further study. Our neural networks seem useful but straightfor- ward, which outperform traditional approaches. What is more, these networks have good generalization. However, because our research field is new, the problems we face are not only various unpredictable parameters but also limited and low-quality training data. To address this, we make two observations: (i) we do not need to learn everything from scratch, we know a lot about the image segmentation area, and (ii) we cannot know everything from data, our models should be aware what key features they should learn. This thesis explores these ideas and even explore more. We show how to use end-to-end deep learning models to learn to retrieve watermark bumps and tackle covariates from a few training images data. Secondly, we introduce ideas from synthetic image data and domain randomization to augment training data and understand various covariates that may affect retrieve real-world 3D watermark bumps. We also show how the illumination in synthetic images data to effect and even improve retrieval accuracy for real-world recognization applications

    Currency design in the United States and abroad: counterfeit deterrence and visual accessibility

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    Despite the increasing use of electronic payments, currency retains an important role in the payment system of every country. In this article, the authors compare and contrast trade-offs among currency design features, including those primarily intended to deter counterfeiting and those to improve usability by the visually impaired. The authors conclude that periodic changes in the design of currency are an important aspect of counterfeit deterrence and that currency designers worldwide generally have been successful in efforts to deter counterfeiting. At the same time, currency designers have sought to be sensitive to the needs of the visually impaired. Although trade-offs among goals sometimes have forced compromises, new technologies promise banknotes that are both more difficult to counterfeit and more accessible to the visually impaired. Among the world's currencies, U.S. banknotes are the notes most widely used outside their country of issue and thus require special consideration.Paper money design - United States ; Money

    Protecting Intellectual Proprietary Rights through Secure Interactive Contract Negotiation

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    Protection of Intellectual Proprietary Rights is currently one of the most important barriers to electronic commerce of digital contents over networks. Authors and content providers understand the immense advantages of the digital world but show some reserve. However, technologies and techniques to protect IPR in digital content exist, their deployment in a coherent way is still in an early stage. In this paper, we describe the approach followed by the OCTALIS Project towards and effective electronic commerce of digital images. After describing briefly enabling technologies, the emphasis is on contract negotiation over Internet through a secure dialog between the Service Provider and the User
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