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Audio Video Interleave
Audio Video Interleave (also Audio Video Interleaved and known by its initials and filename extension AVI, usually pronounced ) is a proprietary multimedia container format and Windows standard introduced by Microsoft in November 1992 as part of its Video for Windows software. AVI files can contain both audio and video data in an uncompressed file container that allows synchronous audio-with-video playback. Like the DVD video format, AVI files support multiple streaming audio and video, although these features are seldom used. Codecs popularly used for AVI include DivX and Xvid, although many other codecs can also be contained in an AVI file. Many AVI files use the file format extensions developed by the Matrox OpenDML group in February 1996. These files are supported by Microsoft, and are unofficially called AVI 2.0. In 2010 the US government's National Archives and Records Administration defined AVI as the official wrapper for preserving digital video. History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IETF
The Internet Engineering Task Force (IETF) is a standards organization for the Internet standard, Internet and is responsible for the technical standards that make up the Internet protocol suite (TCP/IP). It has no formal membership roster or requirements and all its participants are volunteers. Their work is usually funded by employers or other sponsors. The IETF was initially supported by the federal government of the United States but since 1993 has operated under the auspices of the Internet Society, a non-profit organization with local chapters around the world. Organization There is no membership in the IETF. Anyone can participate by signing up to a working group mailing list, or registering for an IETF meeting. The IETF operates in a bottom-up task creation mode, largely driven by working groups. Each working group normally has appointed two co-chairs (occasionally three); a charter that describes its focus; and what it is expected to produce, and when. It is open ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Video
Digital video is an electronic representation of moving visual images (video) in the form of encoded digital data. This is in contrast to analog video, which represents moving visual images in the form of analog signals. Digital video comprises a series of digital images displayed in rapid succession, usually at 24, 30, or 60 frames per second. Digital video has many advantages such as easy copying, multicasting, sharing and storage. Digital video was first introduced commercially in 1986 with the D1 (Sony), Sony D1 format, which recorded an uncompressed standard-definition component video signal in digital form. In addition to uncompressed formats, popular Data compression, compressed digital video formats today include H.264 and MPEG-4. Modern interconnect standards used for playback of digital video include HDMI, DisplayPort, Digital Visual Interface (DVI) and serial digital interface (SDI). Digital video can be copied and reproduced with no degradation in quality. In contra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elsevier
Elsevier ( ) is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', ''Cell (journal), Cell'', the ScienceDirect collection of electronic journals, ''Trends (journals), Trends'', the ''Current Opinion (Elsevier), Current Opinion'' series, the online citation database Scopus, the SciVal tool for measuring research performance, the ClinicalKey search engine for clinicians, and the ClinicalPath evidence-based cancer care service. Elsevier's products and services include digital tools for Data management platform, data management, instruction, research analytics, and assessment. Elsevier is part of the RELX Group, known until 2015 as Reed Elsevier, a publicly traded company. According to RELX reports, in 2022 Elsevier published more than 600,000 articles annually in over 2,800 journals. As of 2018, its archives contained over 17 million documents and 40,000 Ebook, e-books, with over one b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FourCC
A FourCC ("four-character code") is a sequence of four bytes (typically ASCII) used to uniquely identify data formats. It originated from the OSType or ResType metadata system used in classic Mac OS and was adopted for the Amiga/Electronic Arts Interchange File Format and derivatives. The idea was later reused to identify compressed data types in QuickTime and DirectShow. History In 1984, the earliest version of a Macintosh OS, System 1, was released. It used the single-level Macintosh File System with metadata fields including file types, creator (application) information, and forks to store additional resources. It was possible to change this information without changing the data itself, so that they could be interpreted differently. Identical codes were used throughout the system, as type tags for all kinds of data. In 1985, Electronic Arts introduced the Interchange File Format (IFF) meta-format (family of file formats), originally devised for use on the Amiga. These fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RIFF (File Format)
Resource Interchange File Format (RIFF) is a generic file container format for storing data in tagged chunks. It is primarily used for audio and video, though it can be used for arbitrary data. The Microsoft implementation is mostly known through the container formats AVI, ANI and WAV, which use RIFF as their basis. History RIFF was introduced in 1991 by Microsoft and IBM and used as the default format for Windows 3.1 multimedia files. It is based on Interchange File Format introduced by Electronic Arts in 1985 on the Amiga. IFF uses the big-endian convention of the Amiga's Motorola 68000 CPU, but in RIFF multi-byte integers are stored in the little-endian order of the x86 processors used in IBM PC compatibles. A RIFX format, which is big-endian, was also introduced. In 2010 Google introduced the WebP picture format, which uses RIFF as a container. Explanation RIFF files consist entirely of " chunks". The overall format is identical to IFF, except for the endianne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
InfoWorld
''InfoWorld'' (''IW'') is an American information technology media business. Founded in 1978, it began as a monthly magazine. In 2007, it transitioned to a Web-only publication. Its parent company is International Data Group, and its sister publications include '' Macworld'' and '' PC World''. ''InfoWorld'' is based in San Francisco, with contributors and supporting staff based across the U.S. Since its founding, ''InfoWorld''s readership has largely consisted of IT and business professionals. ''InfoWorld'' focuses on how-to, analysis, and editorial content from a mixture of experienced technology journalists and working technology practitioners. The site averages 4.6 million monthly page views and 1.1 million monthly unique visitors. History The magazine was founded by Jim Warren in 1978 as ''The Intelligent Machines Journal'' (IMJ). It was sold to IDG in late 1979. On 18 February 1980, the magazine name was changed to ''InfoWorld''. In 1986, the Robert X. Cringely colum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Codec
A codec is a computer hardware or software component that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder on a signal or data stream, and hence is a type of codec. ''Endec'' is a portmanteau of encoder/decoder. A coder or encoder encodes a data stream or a signal for transmission or storage, possibly in encrypted form, and the decoder function reverses the encoding for playback or editing. Codecs are used in videoconferencing, streaming media, and video editing applications. History Originally, in the mid-20th century, a codec was a hardware device that coded analog signals into digital form using pulse-code modulation (PCM). Later, the term was also applied to software for converting between digital signal formats, including companding functions. Examples An audio codec converts analog audio signals into digital signals for transmissi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lossless Compression
Lossless compression is a class of data compression that allows the original data to be perfectly reconstructed from the compressed data with no loss of information. Lossless compression is possible because most real-world data exhibits statistical redundancy. By contrast, lossy compression permits reconstruction only of an approximation of the original data, though usually with greatly improved compression rates (and therefore reduced media sizes). By operation of the pigeonhole principle, no lossless compression algorithm can shrink the size of all possible data: Some data will get longer by at least one symbol or bit. Compression algorithms are usually effective for human- and machine-readable documents and cannot shrink the size of random data that contain no redundancy. Different algorithms exist that are designed either with a specific type of input data in mind or with specific assumptions about what kinds of redundancy the uncompressed data are likely to contain. Lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PC Magazine
''PC Magazine'' (shortened as ''PCMag'') is an American computer magazine published by Ziff Davis. A print edition was published from 1982 to January 2009. Publication of online editions started in late 1994 and continues . Overview ''PC Magazine'' provides reviews and previews of the latest hardware and software for the information technology professional. Other regular departments include columns by long-time editor-in-chief Michael J. Miller ("Forward Thinking"), Bill Machrone, and Jim Louderback, as well as: * "First Looks" (a collection of reviews of newly released products) * "Pipeline" (a collection of short articles and snippets on computer-industry developments) * "Solutions" (which includes various how-to articles) * "User-to-User" (a section in which the magazine's experts answer user-submitted questions) * "After Hours" (a section about various computer entertainment products; the designation "After Hours" is a legacy of the magazine's traditional orientation to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lossy Compression
In information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data size for storing, handling, and transmitting content. Higher degrees of approximation create coarser images as more details are removed. This is opposed to lossless data compression (reversible data compression) which does not degrade the data. The amount of data reduction possible using lossy compression is much higher than using lossless techniques. Well-designed lossy compression technology often reduces file sizes significantly before degradation is noticed by the end-user. Even when noticeable by the user, further data reduction may be desirable (e.g., for real-time communication or to reduce transmission times or storage needs). The most widely used lossy compression algorithm is the discrete cosine transform (DCT), first published by N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megabyte
The megabyte is a multiple of the unit byte for digital information. Its recommended unit symbol is MB. The unit prefix ''mega'' is a multiplier of (106) in the International System of Units (SI). Therefore, one megabyte is one million bytes of information. This definition has been incorporated into the International System of Quantities. In the computer and information technology fields, other definitions have been used that arose for historical reasons of convenience. A common usage has been to designate one megabyte as (220 B), a quantity that conveniently expresses the binary architecture of digital computer memory. Standards bodies have deprecated this binary usage of the mega- prefix in favor of a new set of binary prefixes, by means of which the quantity 220 B is named mebibyte (symbol MiB). Definitions The unit megabyte is commonly used for 10002 (one million) bytes or 10242 bytes. The interpretation of using base 1024 originated as technical jargon for the byte m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Super VGA
Super VGA (SVGA) or Extended VGA is a broad term that covers a wide range of computer display standards that extended IBM's VGA specification. When used as shorthand for a resolution, as VGA and XGA often are, SVGA refers to a resolution of 800 × 600. History In the late 1980s, after the release of IBM's VGA, third-party manufacturers began making graphics cards based on its specifications with extended capabilities. As these cards grew in popularity, they began to be referred to as "Super VGA". This term was not an official standard, but a shorthand for enhanced VGA cards which had become common by 1988. The first cards that explicitly used the term were Genoa Systems's SuperVGA and SuperVGA HiRes in 1987. Super VGA cards broke compatibility with the IBM VGA standard, requiring software developers to provide specific display drivers and implementations for each card their software could operate on. Initially, the heavy restrictions this placed on software develop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
