|
Copy Detection Pattern
A copy detection pattern (CDP) or graphical code is a small random or 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 than an original CDP. By measu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Randomness
In common usage, randomness is the apparent or actual lack of definite pattern or predictability in information. 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 there is a known probability distribution, 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. Consistent non-convergence is thus evidence of the lack of a fixed probability distribution, as in many evolutionary processes. 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 haphaza ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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. 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 (i.e. to assert that it is not counterfeit), or in a given period of history (e.g. by determining the age via carbon dating). In computer science, verifying a user's identity is often required to allow access to confidential data or systems. It might involve validating personal identity documents. In art, antiques and anthropology Authentication can be considered to be of three types: The ''first'' type of authentication is accepting proof of identity given by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Watermarks
A digital watermark is a kind of marker covertly embedded in a noise-tolerant signal such as audio, video or image data.H.T. Sencar, M. Ramkumar and A.N. Akansu: ''Data Hiding Fundamentals and Applications: Content Security in Digital Multimedia''. Academic Press, San Diego, CA, USA, 2004. It is typically used to identify ownership of the copyright of such a signal. Digital 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. aft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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, cheques, and ownership title certificate 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 such documents 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 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 IS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FIFA World Cup
The FIFA World Cup, often called the World Cup, is an international association football competition among the senior List of men's national association football teams, men's national teams of the members of the FIFA, Fédération Internationale de Football Association (FIFA), the sport's global governing body. The tournament has been held every four years since the 1930 FIFA World Cup, inaugural tournament in 1930, with the exception of 1942 and 1946 due to the Second World War. The reigning champions are Argentina national football team, Argentina, who won their third title at the 2022 FIFA World Cup, 2022 World Cup by defeating France national football team, France. The contest starts with the FIFA World Cup qualification, 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 the course of about a month. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Identity Document
An identity document (abbreviated as ID) is a documentation, document proving a person's Identity (social science), identity. If the identity document is a plastic card it is called an ''identity card'' (abbreviated as ''IC'' or ''ID card''). When the identity document incorporates a photographic portrait, it is called a ''Photo identification, photo ID''. In some countries, identity documents may be List of national identity card policies by country#Countries with compulsory identity cards, compulsory to have. The identity document is used to connect a person to information about the person, often in a database. The connection between the identity document and database is based on personal information present on the document, such as the bearer's full name, birth date, Address (geography), address, an identification number, card number, gender, citizenship and more. A unique national identification number is the most secure way, but some countries lack such numbers or do not s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Of Things
Internet of things (IoT) describes devices with sensors, processing ability, software and other technologies that connect and exchange data with other devices and systems over the Internet or other communication networks. The IoT encompasses Electronic engineering, electronics, Telecommunications engineering, communication, and computer science engineering. "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, and 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. . Older fields of embedded systems, wireless sensor netw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaussian Noise
Carl Friedrich Gauss (1777–1855) is the eponym of all of the topics listed below. There are over 100 topics all named after this German mathematician and scientist, all in the fields of mathematics, physics, and astronomy. The English eponymous adjective ''Gaussian'' is pronounced . Mathematics Algebra and linear algebra Geometry and differential geometry Number theory Cyclotomic fields *Gaussian period *Gaussian rational *Gauss sum, an exponential sum over Dirichlet characters **Elliptic Gauss sum, an analog of a Gauss sum **Quadratic Gauss sum Analysis, numerical analysis, vector calculus and calculus of variations Complex analysis and convex analysis *Gauss–Lucas theorem *Gauss's continued fraction, an analytic continued fraction derived from the hypergeometric functions *Gauss's test, Gauss's criterion – described oEncyclopedia of Mathematics*Gauss's hypergeometric theorem, an identity on hypergeometric series *Gauss plane Statistics *Gaus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
