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Copy Detection Pattern
A copy detection pattern (CDP) or graphical code is a small Randomness, random or Pseudorandomness, pseudo-random digital image which is printed on documents, labels or products for counterfeit detection. Authentication is made by scanning the printed CDP using an image scanner or mobile phone camera. It is possible to store additional product-specific data into the CDP that will be decoded during the scanning process. A CDP can also be inserted into a 2D barcode to facilitate smartphone authentication and to connect with traceability data. Principle The detection of counterfeits using a CDP relies on an "information loss principle", which states that every time a digital image is printed or scanned, some information about the original digital image is lost. A CDP is a maximum entropy image that attempts to take advantage of this information loss. Since producing a counterfeit CDP requires an additional scanning and printing processes, it will have less information tha ...
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Randomness
In common usage, randomness is the apparent or actual lack of pattern or predictability in events. A random sequence of events, symbols or steps often has no order and does not follow an intelligible pattern or combination. Individual random events are, by definition, unpredictable, but if the probability distribution is known, the frequency of different outcomes over repeated events (or "trials") is predictable.Strictly speaking, the frequency of an outcome will converge almost surely to a predictable value as the number of trials becomes arbitrarily large. Non-convergence or convergence to a different value is possible, but has probability zero. For example, when throwing two dice, the outcome of any particular roll is unpredictable, but a sum of 7 will tend to occur twice as often as 4. In this view, randomness is not haphazardness; it is a measure of uncertainty of an outcome. Randomness applies to concepts of chance, probability, and information entropy. The fields of ...
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Cdp Digital Original Copy
CDP may refer to: Places * Census-designated place, an unincorporated area in the U.S. for which census data is collected * Cuddapah Airport (IATA identifier: CDP), Andhra Pradesh, India Technology * Cache Discovery Protocol, an extension to the BitTorrent file-distribution system * Certificate in Data Processing, a professional certification conferred by the ICCP * Charger Downstream Port, a type of battery-charging USB port * Cisco Discovery Protocol, a proprietary data link network protocol developed by Cisco Systems * Columbia Data Products, formerly a computer manufacturer, now a software company * Composers Desktop Project, non-realtime audio digital-signal processing (DSP) software * Content delivery platform, a system for managing and deploying web content * Continuous Data Protection, whereby computer data is continuously backed up * Customer data platform, marketer-based management system for customer profiles Science and medicine * Coronary Drug Project, a t ...
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Authentication Methods
Authentication (from ''authentikos'', "real, genuine", from αὐθέντης ''authentes'', "author") is the act of proving an assertion, such as the identity of a computer system user. In contrast with identification, the act of indicating a person or thing's identity, authentication is the process of verifying that identity. It might involve validating personal identity documents, verifying the authenticity of a website with a digital certificate, determining the age of an artifact by carbon dating, or ensuring that a product or document is not counterfeit. Methods Authentication is relevant to multiple fields. In art, antiques, and anthropology, a common problem is verifying that a given artifact was produced by a certain person or in a certain place or period of history. In computer science, verifying a user's identity is often required to allow access to confidential data or systems. Authentication can be considered to be of three types: The first type of auth ...
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Digital Watermarks
A digital watermark is a kind of marker covertly embedded in a noise-tolerant signal such as audio, video or image data. It is typically used to identify ownership of the copyright of such signal. "Watermarking" is the process of hiding digital information in a carrier signal; the hidden information should,Ingemar J. Cox: ''Digital watermarking and steganography''. Morgan Kaufmann, Burlington, MA, USA, 2008 but does not need to, contain a relation to the carrier signal. Digital watermarks may be used to verify the authenticity or integrity of the carrier signal or to show the identity of its owners. It is prominently used for tracing copyright infringements and for banknote authentication. Like traditional physical watermarks, digital watermarks are often only perceptible under certain conditions, e.g. after using some algorithm.Frank Y. Shih: ''Digital watermarking and steganography: fundamentals and techniques''. Taylor & Francis, Boca Raton, FL, USA, 2008 If a digital watermark ...
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EURion Constellation
The EURion constellation (also known as Omron rings or doughnuts) is a pattern of symbols incorporated into a number of secure documents such as banknotes and ownership title certificates designs worldwide since about 1996. It is added to help imaging software detect the presence of such a document in a digital image. Such software can then block the user from reproducing banknotes to prevent counterfeiting using colour photocopiers. Description The name "EURion constellation" was coined by security researcher Markus Kuhn, who uncovered the pattern on the 10 Euro (€10) banknote in early 2002 while experimenting with a Xerox colour photocopier that refused to reproduce banknotes. Markus KuhnThe EURion constellation Security Group presentation, Computer Laboratory, University of Cambridge, 8 February 2002. The pattern has never been mentioned officially; Kuhn named it the EURion constellation as it resembled the astronomical Orion constellation, and EUR is the ISO 4217 ...
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QR Code
A QR code (an initialism for quick response code) is a type of matrix barcode (or two-dimensional barcode) invented in 1994 by the Japanese company Denso Wave. A barcode is a machine-readable optical label that can contain information about the item to which it is attached. In practice, QR codes often contain data for a locator, identifier, or tracker that points to a website or application. QR codes use four standardized encoding modes (numeric, alphanumeric, byte/binary, and kanji) to store data efficiently; extensions may also be used. The quick response system became popular outside the automotive industry due to its fast readability and greater storage capacity compared to standard UPC barcodes. Applications include product tracking, item identification, time tracking, document management, and general marketing. A QR code consists of black squares arranged in a square grid on a white background, including some fiducial markers, which can be read by an imaging device suc ...
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FIFA World Cup
The FIFA World Cup, often simply called the World Cup, is an international association football competition contested by the senior men's national teams of the members of the ' ( FIFA), the sport's global governing body. The tournament has been held every four years since the inaugural tournament in 1930, except in 1942 and 1946 when it was not held because of the Second World War. The reigning champions are Argentina, who won their third title at the 2022 tournament. The format involves a qualification phase, which takes place over the preceding three years, to determine which teams qualify for the tournament phase. In the tournament phase, 32 teams compete for the title at venues within the host nation(s) over about a month. The host nation(s) automatically qualify to the group stage of the tournament. As of the 2022 FIFA World Cup, 22 final tournaments have been held and a total of 80 national teams have competed. The trophy has been won by eight national teams. ...
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Identity Document
An identity document (also called ID or colloquially as papers) is any documentation, document that may be used to prove a person's identity. If issued in a small, standard credit card size form, it is usually called an identity card (IC, ID card, citizen card), or passport card. Some countries issue formal identity documents, as national identification cards that may be List of national identity card policies by country#Countries with compulsory identity cards, compulsory or List of national identity card policies by country#Countries with non-compulsory identity cards, non-compulsory, while others may require identity verification using regional identification or informal documents. When the identity document incorporates a person's photograph, it may be called Photo identification, photo ID. In the absence of a formal identity document, a driver's license may be accepted in many countries for Identity verification service, identity verification. Some countries do not accept ...
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Internet Of Things
The Internet of things (IoT) describes physical objects (or groups of such objects) with sensors, processing ability, software and other technologies that connect and exchange data with other devices and systems over the Internet or other communications networks. Internet of things has been considered a misnomer because devices do not need to be connected to the public internet, they only need to be connected to a network and be individually addressable. The field has evolved due to the convergence of multiple technologies, including ubiquitous computing, commodity sensors, increasingly powerful embedded systems, as well as machine learning.Hu, J.; Niu, H.; Carrasco, J.; Lennox, B.; Arvin, F.,Fault-tolerant cooperative navigation of networked UAV swarms for forest fire monitoring Aerospace Science and Technology, 2022. Traditional fields of embedded systems, wireless sensor networks, control systems, automation (including Home automation, home and building automation), indepen ...
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Correlation Function
A correlation function is a function that gives the statistical correlation between random variables, contingent on the spatial or temporal distance between those variables. If one considers the correlation function between random variables representing the same quantity measured at two different points, then this is often referred to as an autocorrelation function, which is made up of autocorrelations. Correlation functions of different random variables are sometimes called cross-correlation functions to emphasize that different variables are being considered and because they are made up of cross-correlations. Correlation functions are a useful indicator of dependencies as a function of distance in time or space, and they can be used to assess the distance required between sample points for the values to be effectively uncorrelated. In addition, they can form the basis of rules for interpolating values at points for which there are no observations. Correlation functions used ...
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Gaussian Noise
Gaussian noise, named after Carl Friedrich Gauss, is a term from signal processing theory denoting a kind of signal noise that has a probability density function (pdf) equal to that of the normal distribution (which is also known as the Gaussian distribution). In other words, the values that the noise can take are Gaussian-distributed. The probability density function p of a Gaussian random variable z is given by: : p_G(z) = \frac e^ where z represents the grey level, \mu the mean grey value and \sigma its standard deviation. A special case is ''White Gaussian noise'', in which the values at any pair of times are identically distributed and statistically independent (and hence uncorrelated). In communication channel testing and modelling, Gaussian noise is used as additive white noise to generate additive white Gaussian noise. In telecommunications and computer networking, communication channels can be affected by wideband Gaussian noise coming from many natural sources, su ...
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