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DigiCipher
DigiCipher 2, or simply DCII, is a proprietary standard format of digital signal transmission and it doubles as an encryption standard with MPEG-2/MPEG-4 signal video compression used on many communications satellite television and audio signals. The DCII standard was originally developed in 1997 by General Instrument, which then became the Home and Network Mobility division of Motorola, then bought by Google in Aug 2011, and lastly became the Home portion of the division to Arris Group, Arris. The original attempt for a North American digital signal encryption and compression standard was DigiCipher 1, which was used most notably in the now-defunct PrimeStar medium-power direct broadcast satellite (DBS) system during the early 1990s. The DCII standard predates wide acceptance of Digital Video Broadcasting, DVB-based digital terrestrial television compression (although not cable or satellite DVB) and therefore is incompatible with the DVB standard. Approximately 70% of newer first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Television
Satellite television is a service that delivers television programming to viewers by relaying it from a communications satellite orbiting the Earth directly to the viewer's location.ITU Radio Regulations, Section IV. Radio Stations and Systems – Article 1.39, definition: ''Broadcasting-satellite service'' The signals are received via an outdoor parabolic antenna commonly referred to as a satellite dish and a low-noise block downconverter. A satellite receiver decodes the desired television program for viewing on a television set. Receivers can be external set-top boxes, or a built-in television tuner. Satellite television provides a wide range of channels and services. It is usually the only television available in many remote geographic areas without terrestrial television or cable television service. Different receivers are required for the two types. Some transmissions and channels are unencrypted and therefore free-to-air, while many other channels are transmitted with enc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shaw Direct
Shaw Direct G.P. is a direct broadcast satellite television distributor in Canada and a subsidiary of the telecommunications company Rogers Communications. As of 2010, Shaw Direct had over 900,000 subscribers. It broadcasts on Ku band from two communications satellites: Anik G1 at 107.3°W, and Anik F2 at 111.1°W. Anik F1R, which had been in service for 15 years, reached its end of life in the latter part of 2020, when the services on this satellite were migrated between the remaining two. These satellites are owned by Telesat Canada and otherwise are used primarily to distribute programming to various Canadian cable TV companies. The company was formerly known as Star Choice until April 15, 2009. A full list of channels carried by these two satellites is available from satellite-related sites such as Lyngsat. The newer of the two satellites, Anik G1, was launched on April 15, 2013, and then later reached orbit on May 29, 2013. Shaw Direct was founded in Lincoln, New Brun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Direct Broadcast Satellite
Satellite television is a service that delivers television programming to viewers by relaying it from a communications satellite orbiting the Earth directly to the viewer's location.ITU Radio Regulations, Section IV. Radio Stations and Systems – Article 1.39, definition: ''Broadcasting-satellite service'' The signals are received via an outdoor parabolic antenna commonly referred to as a satellite dish and a low-noise block downconverter. A satellite receiver decodes the desired television program for viewing on a television set. Receivers can be external set-top boxes, or a built-in television tuner. Satellite television provides a wide range of channels and services. It is usually the only television available in many remote geographic areas without terrestrial television or cable television service. Different receivers are required for the two types. Some transmissions and channels are unencrypted and therefore free-to-air, while many other channels are transmitted wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4DTV
4DTV is a proprietary broadcasting standard and technology for digital cable broadcasting and C-band/Ku-band satellite dishes from Motorola, using General Instrument's DigiCipher II for encryption. It can tune in both analog VideoCipher II and digital DCII satellite channels. History 4DTV technology was originally developed in 1997 (the same year that DigiCipher was developed) by General Instrument/NextLevel and Motorola, now a division of ARRIS. The 4DTV format is contemporary to the DVB-based digital television broadcast standard but its completion came before that of DVB and thus it is similar but incompatible with the DVB standard. The DigiCipher 2 encryption system is used in digital channels much like the VideoCipher and VideoCipher II systems were used for analog encrypted transmissions. By the time when analogue VideoCipher II channels are switched to digital, all of the remaining VCII-encrypted channels (excluding in the clear) are transitioned to DigiCipher II ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1997 Introductions
Events January * January 1 – The Emergency Alert System is introduced in the United States. * January 11 – Turkey threatens Cyprus on account of a deal to buy Russian S-300 missiles, prompting the Cypriot Missile Crisis. * January 16 – Murder of Ennis Cosby: Near Interstate 405 (California) on a Los Angeles freeway, Bill Cosby's son Ennis is shot in the head in a failed robbery attempt. * January 17 – A Delta II rocket carrying a military GPS payload explodes, shortly after liftoff from Cape Canaveral. * January 18 – In northwest Rwanda, Hutu militia members kill 6 Spanish aid workers and three soldiers, and seriously wound another. * January 19 – Yasser Arafat returns to Hebron after more than 30 years, and joins celebrations over the handover of the last Israeli-controlled West Bank city. (→ Hebron Agreement) * January 23 – Madeleine Albright becomes the first female Secretary of State of the United States, after confirmation by the United States Se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Rights Management Systems
Digital usually refers to something using discrete digits, often binary digits. Businesses *Digital bank, a form of financial institution *Digital Equipment Corporation (DEC) or Digital, a computer company *Digital Research (DR or DRI), a software company Computing and technology Hardware *Digital electronics, electronic circuits which operate using digital signals **Digital camera, which captures and stores digital images *** Digital versus film photography **Digital computer, a computer that handles information represented by discrete values **Digital recording, information recorded using a digital signal Socioeconomic phenomena *Digital culture, the anthropological dimension of the digital social changes *Digital divide, a form of economic and social inequality in access to or use of information and communication technologies * Digital economy, an economy based on computing and telecommunications resources *Digital rights, legal rights of access to computers or the Internet O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Television Terminology
Television (TV) is a telecommunication medium for transmitting moving images and sound. Additionally, the term can refer to a physical television set rather than the medium of transmission. Television is a mass medium for advertising, entertainment, news, and sports. The medium is capable of more than "radio broadcasting", which refers to an audio signal sent to radio receivers. Television became available in crude experimental forms in the 1920s, but only after several years of further development was the new technology marketed to consumers. After World War II, an improved form of black-and-white television broadcasting became popular in the United Kingdom and the United States, and television sets became commonplace in homes, businesses, and institutions. During the 1950s, television was the primary medium for influencing public opinion.Diggs-Brown, Barbara (2011''Strategic Public Relations: Audience Focused Practice''p. 48 In the mid-1960s, color broadcasting was in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Television
Digital television (DTV) is the transmission of television signals using Digital signal, digital encoding, in contrast to the earlier analog television technology which used analog signals. At the time of its development it was considered an innovative advancement and represented the first significant evolution in television technology since color television in the 1950s. Modern digital television is transmitted in high-definition television (HDTV) with greater resolution than analog TV. It typically uses a widescreen aspect ratio (commonly 16:9) in contrast to the narrower format (4:3) of analog TV. It makes more economical use of scarce radio spectrum space; it can transmit up to seven channels in the same Bandwidth (signal processing), bandwidth as a single analog channel, and provides many new features that analog television cannot. A digital television transition, transition from analog to digital broadcasting began around 2000. Different digital television broadcasting st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptographic Protocols
A cryptographic protocol is an abstract or concrete protocol that performs a security-related function and applies cryptographic methods, often as sequences of cryptographic primitives. A protocol describes how the algorithms should be used and includes details about data structures and representations, at which point it can be used to implement multiple, interoperable versions of a program. Cryptographic protocols are widely used for secure application-level data transport. A cryptographic protocol usually incorporates at least some of these aspects: * Key agreement or establishment * Entity authentication * Symmetric encryption and message authentication material construction * Secured application-level data transport * Non-repudiation methods * Secret sharing methods * Secure multi-party computation For example, Transport Layer Security (TLS) is a cryptographic protocol that is used to secure web (HTTPS) connections. It has an entity authentication mechanism, based on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolby Digital
Dolby Digital, originally synonymous with Dolby AC-3 (see below), is the name for a family of audio compression technologies developed by Dolby Laboratories. Called Dolby Stereo Digital until 1995, it is lossy compression (except for Dolby TrueHD). The first use of Dolby Digital was to provide digital sound in cinemas from 35 mm film prints. It has since also been used for TV broadcast, radio broadcast via satellite, digital video streaming, DVDs, Blu-ray discs and game consoles. Dolby AC-3 was the original version of the Dolby Digital codec. The basis of the Dolby AC-3 multi-channel audio coding standard is the modified discrete cosine transform (MDCT), a lossy audio compression algorithm. It is a modification of the discrete cosine transform (DCT) algorithm, which was proposed by Nasir Ahmed in 1972 for image compression. The DCT was adapted into the MDCT by J.P. Princen, A.W. Johnson and Alan B. Bradley at the University of Surrey in 1987. Dolby Laboratories adap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Huffman Coding
In computer science and information theory, a Huffman code is a particular type of optimal prefix code that is commonly used for lossless data compression. The process of finding or using such a code is Huffman coding, an algorithm developed by David A. Huffman while he was a Doctor of Science, Sc.D. student at Massachusetts Institute of Technology, MIT, and published in the 1952 paper "A Method for the Construction of Minimum-Redundancy Codes". The output from Huffman's algorithm can be viewed as a variable-length code table for encoding a source symbol (such as a character in a file). The algorithm derives this table from the estimated probability or frequency of occurrence (''weight'') for each possible value of the source symbol. As in other entropy encoding methods, more common symbols are generally represented using fewer bits than less common symbols. Huffman's method can be efficiently implemented, finding a code in time linear time, linear to the number of input weigh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
