Text encoding - Text encoding A text encoding is a method of representing a piece of text as a sequence of codes (from a character encoding) for the purpose of computer storage or electronic communication of that text. While character encodings like ASCII represent individual characters of a language, a text encoding has to represent much larger things like articles and books, and must represent not only the characters they contain but the structure and organization}} of the text, and perhaps [[information about the text or its appearance. Common examples are HTML and RTF which represent texts in natural languages, and XML, which can represent many kinds of text not necessarily intended to be human-readable (the contents of a database, for example). In general there are two basic forms.
Teletext - be viewed on television sets with suitable decoders. They offer a range of text-based information, usually including national, international and sporting news, weather and TV schedules. Subtitle (or closed caption) information is also transmitted in the teletext signal. Teletext is widely used across Europe, with every main television station having its own teletext service. In some commercial stations the teletext is also used as a publicity channel, advertising products such as travel destinations. Common teletext services include TV schedules, regularly updated current affairs and sport news, simple games (like quizzes) and subtitling for deaf people or in different languages. Table of contents showTocToggle("show","hide") 1 History 2 Description 3 See also 4 External Links 4.1 Teletext content on the Internet History The BBC started an engineering project in 1970 or 1971 on.
Bi-directional text - Bi-directional text The writing systems of some languages, such as Hebrew and Arabic are written from right to left. When Latin-based text is mixed with these languages in the same sentence, each type of text should be written in its own direction. This is known as bi-directional text. This can get quite complex when multiple levels of quotation are used. Many computer programs fail to display bi-directional text correctly. For example, the Hebrew Tetragrammaton (יהוה) should be spelled yodh(י) heh(ה) waw(ו) heh(ה) from right to left. Some web browsers may display the Hebrew text in this article in the opposite direction. Very few languages may be written in either direction. Such was the case with Egyptian hieroglyphics, where the signs had a distinct "head" that faced the beginning.
Binary and text files - Binary and text files Computer files can be divided into two broad category: binary and text. The distinction is subtle because to computers, any file is a sequence of digital bits. Text files (plain text files) are files with generally a one-to-one correspondence between the bytes and ordinary readable characters such as letters and digits. Therefore any simple program to view a file makes them human-readable. Generally, they contain ASCII characters and some control characters such as tabs, line feeds and carriage returns without any embedded information such as font information, hyperlinks or inline images. But sometimes text files contain more than ASCII characters if they are encoded by East-Asian encoding such as SJIS or unicode. If the files are written in unicode, a UTF standard such.
Character encoding - Character encoding A character encoding is a code that pairs a set of natural language characters (such as an alphabet or syllabary) with a set of something else, such as numbers or electrical pulses. Common examples include Morse code, which encodes letters of the Roman alphabet as series of long and short depressions of a telegraph key; and ASCII, which encodes letters, numerals, and other symbols as both integers and 7-bit binary versions of those integers. In some contexts (especially computer storage and communication) it makes sense to distinguish a character repertoire, which is a full set of abstract characters that a system supports, from a coded character set or character encoding which specifies how to represent characters from that set using a number of integer codes..
Character encodings in HTML - the HTML document, and proper display of the document by the largest possible variety of browsers. The document character set When HTML documents are served to the viewer, there are two ways to tell the browser what specific character encoding is used. First, HTTP headers can be sent by the server along with each page. A typical header looks like this: Content-Type: text/html; charset=ISO-8859-1 The other method is for the HTML document to include this information at its top, inside the HEAD element. Either method advises the receiver that the file being sent uses the character set specified. Of course, it would be a very bad idea to send incorrect information. For example, a server where multiple users may place files created on different machines cannot promise.
Specific Area Message Encoding - Specific Area Message Encoding Specific Area Message Encoding or SAME is the protocol used to encode the Emergency Alert System in the U.S for broadcast stations. It was originally created for weatheradio by the National Weather Service, and was later adopted by the FCC for regular broadcasters on radio, television, and cable. The system transmits digital tones over normal audio using AFSK, with a 2083.3Hz mark tone and 1562.5Hz space tone, lasting 1920μs (1.92ms) each. The data is encoded in 7-bit ASCII but uses all 8 bits, with no parity bit and no stop bit ("8-N-0"), at a bitrate of 520.83 bits per second. In the SAME system, messages are constructed in four parts, the first and last of which are digital. The first part is the AFSK-encoded header.
Run-length encoding - Run-length encoding Run-length encoding (RLE) is a very simple form of data compression in which runs of data (that is, sequences in which the same data value occurs in many consecutive data elements) are stored as a single data value and count, rather than as the original run. This is most useful on data that contains many such runs; for example, simple graphic images such as icons and line drawings. For example, consider a screen containing plain black text on a solid white background. There will be many long runs of white pixels in the blank space, and many short runs of black pixels within the text. Let us take a hypothetical single scan line, with B representing a black pixel and W representing white: WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW If we.
Japanese language and computers - adaptation issues arise. Many problems relate to transliteration and romanization, some to character encoding, and some to the input of Japanese text. Table of contents showTocToggle("show","hide") 1 Romanization 2 Character Encoding 3 Input method 4 Gaiji 5 See Also Romanization Modern Japanese is usually input into a computer via romanization. There are two main systems for the romanization of Japanese, known as Kunrei-shiki and Hepburn. The Kunrei system is used widely in Japan for input on a roman keyboard, since it is slightly briefer and more systematic than the Hepburn system. Foreigners typically prefer the Hepburn system however, because the Kunrei system does not correspond as well to the actual sounds of Japanese. Character Encoding There are several standard methods to encode characters for use on a computer, including JIS, SJIS,.
Invisible ink - a radiator, iron or oven for example. Other types of invisible ink use different chemical reactions, usually an acid-base reaction (like litmus paper) similar to the blueprint process. These dual chemical ink/decoder pairs use a spray bottle for the decoding liquid or vapor (e.g. for ammonia fumes to decode phenolphthalein ink), or an invisible ink pen with two tips, one the encoding tip, and one the decoding. A cover message should be written over the invisible message, since a blank sheet of paper arouses suspicion. Invisible ink is sometimes used to print parts of pictures or text in books for children to play with, particularly while they are travelling. A decoding pen is included with these books so that the children may rub the decoding pen over the invisible part of.
VP3.2 Public License - \r\nThe Initial Developer hereby grants You a world-wide, royalty-free, non-\r\nexclusive license, subject to third party intellectual property claims: \r\n\r\n(a) under intellectual property rights (other than patent or trademark) \r\nLicensable by Initial Developer to use, reproduce, modify, display, perform, \r\nsublicense and distribute the Original Code (or portions thereof) with or \r\nwithout Modifications, and/or as part of a Larger Work; and \r\n\r\n(b) under Patents Claims infringed by the making, using or selling of Original \r\nCode, to make, have made, use, practice, sell, and offer for sale, and/or \r\notherwise dispose of the Original Code (or portions thereof). \r\n \r\n(c) the licenses granted in this Section 2.1(a) and (b) are effective on the \r\ndate Initial Developer first distributes Original Code under the terms of this \r\nLicense. \r\n\r\n(d) Notwithstanding Section 2.1(b) above, no patent license is.
Huffman coding - In computer science, Huffman coding is an entropy encoding algorithm used for data compression. It was developed by David A. Huffman and published 1952 A Method for the Construction of Minimum-Redundancy Codes. The basic idea is borrowed from an older and slightly less efficient method called Shannon-Fano coding. The text to be compressed is considered as a string of symbols. Symbols that are likely to be frequent are represented by a short sequence of bits, and symbols that are likely to be rare are represented by a longer sequences of bits. Huffman coding uses a specific method for choosing the representations for each symbol, resulting in a prefix-free code (i.e. no bit string of any symbol is a prefix of the bit string of any other symbol). It has been proven.
GEDCOM - GEDCOM is an acronym for GEnealogical Data COMunication. A GEDCOM file is plain text (often in ASCII in the United States, although technically the standard mandates use of an obscure text encoding named ANSEL) containing records for each individual in the family tree, and data linking these records together. GEDCOM was developed by The Church of Jesus Christ of Latter-day Saints as an aid in their extensive genealogical research. Most (if not all) genealogy software supports importing from and/or exporting to GEDCOM format. Additionally, many tools exist to convert GEDCOM files to HTML pages. Although it is theoretically possible to write a GEDCOM file by hand, the format was designed for export and import by software, and is not especially human-friendly. GEDCOM File Structure A GEDCOM file consists of a header.
Unicode and HTML - non-Latin-1 characters can be obtained by using the browser Mozilla, where, after typing in text edit box and saving page, the characters automatically convert into Unicode. Usually though, an 8-bit character encoding is used that can only represent a small slice of this set. It is still possible to have characters from the whole of Unicode inside an HTML document by using a numeric character entity reference &#N;, where N is a decimal number for the Unicode code point, or a hexadecimal number prefixed by x. The support for hexadecimal in this context is more recent, so older browsers might have problems displaying those characters – but they will probably have a problem displaying Unicode characters outside the 8-bit range in the first place. It is still a common practice to.
GIS file formats - formats A GIS file format is a standard of encoding geographical information into a file. They are created mainly by government mapping agencies (such as the USGS) or by GIS software developers. Metadata often includes: Elevation data, either in raster or vector form (e.g., contours) Shape layers, usually expressed as line drawings, for streets, postal zone boundaries, etc. Coordinate system descriptions. One or more datums describing the precise shape of the Earth assumed by the coordinates. Popular GIS file formats USGS DEM - US Geo Survey Digital Elevation Model SDTS - The USGS' successor to DEM BIL - Binary Interleave GTOPO30 - Large "complete Earth" coverage filesets XYZ - Simple point cloud GeoTIFF - TIFF variant expressly for GIS data NTF - UK Ordnance Survey ASC - Simple ASCII text point.
Glossary of telecommunications encryption terms - copyright-related issues, as not all parts of the source document are in the public domain. bulk encryption -- cipher -- cipher system -- cipher text -- ciphony -- civision -- codress message -- compromise -- COMSEC equipment -- cover -- cryptanalysis -- CRYPTO -- Data Encryption Standard (DES) -- decipher -- decode -- decrypt -- descrambler -- encipher -- encode -- encoding law -- encrypt -- end-to-end encryption -- garble -- group -- key -- key distribution center (KDC) -- key management -- key stream -- link encryption -- multiplex link encryption -- net control station (NCS) -- null -- OTAR -- plain text -- protected distribution system (PDS) -- protection interval (PI) -- pseudorandom number generator -- public key cryptography -- RED/BLACK concept -- RED signal -- rekeying -- remote.
Grave accent - versus ó [o]. In Italian, it marks final stress, as in virtù ("virtue") or città ("city"). In Vietnamese and some other tonal languages, the grave accent is used to indicate a falling tone. The grave accent is used in English only in poetry and song lyrics. It indicates that a vowel usually silent is to be pronounced, in order to fit the rhythm or meter. Most often, it is applied to a word ending with -ed. For instance, the word looked is usually pronounced as a single syllable, with the e silent; when written as lookèd, the e is pronounced -- look-ed. Using the ISO-8859-1 character encoding, one can type the letters à, è, ì, ò, and ù. Dozens more letters with the grave accent are available in Unicode. Unicode also.
Fax - was invented in 1929 by Rudolf Hell. The most basic fax mode transfers black and white only. The original page is scanned in a resolution of 1728 pixels/line and 1145 lines/page (A4). The resulting raw data is compressed using a modified Huffman code optimized for written text, achieving average compression factors of around 20. Typically a page needs 10 s for transmission, instead of about 3 minutes for the same uncompressed raw data of 1728×1145 bits at a speed of 9600 bit/s. The compression method uses a Huffman codebook for run lengths of black and white runs in a single scanned line, and it also uses the fact that two adjacent scanlines are usually quite similar, saving bandwidth by encoding only the differences. There are different fax classes, like Class 1,.
File format - can be created, however this is optional, and the use of extensions under these systems is seen as a convenience and not a requirement. Under these systems, all files, basically, are seen as data files, directories (which indeed are a special kind of file), or as executables. Operating system settings determine which program is executed by default on "opening" a file with a particular extension. For example, if a file has extension .htm, the setting determines whether a web browser is used to interpret the HTML (and which one) or whether it is an editor or text viewer that displays the HTML code. Many file formats, and some well-known file formats, have a published specification document (often with a reference implementation) that describes exactly how the data is to be encoded,.
Four-stage model of data compression - scope of "Organization by Context." In lossy systems, any loss is usually introduced in (A), so remaining steps are the same for both lossy and lossless. Organization by context Organization by context often means data reordering, for which a simple example is JPEG's `Zigzag' ordering -- a simple device to sequence a vector's elements into approximate order of expected energy (or bit rate requirement). (One important but little-remarked reason why more modern zerotree-type image compressors outperform JPEG is that they bunch similar statistics across very large image areas, while JPEG just does a 64-pel block.) More generally, context organization includes separation and concatenation to move data with similar context, such as adjacent pixel values, to adjacent locations in an encoding stream, or to provide a similar context character to a context-conditioned.
