JPEG

JPEG
JPEG (jāʹpĕg') n. Computer Science
1. The standard algorithm for the compression of digital images.
2. A digital image stored as a file so compressed:

e-mailed me a JPEG of her house.

  [J(oint) P(hotographic) E(xperts) G(roup).]

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in full Joint Photographic Experts Group

Standard computer file format for storing graphic images in a compressed form for general use.

JPEG images are compressed using a mathematical algorithm. A variety of encoding processes can be used, depending on whether the user's goal is the highest quality of image (lossless) or smallest file size (lossy). The JPEG and GIF formats are the most commonly used graphics formats on the Internet for lossy and lossless data compression, respectively.

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in full  Joint Photographic Experts Group 

      a computer graphics file format.

      In 1983 researchers with the International Organization for Standardization (ISO) started working on ways to add photo-quality graphics to the text-only computer terminal screens of the day. Three years later, the Joint Photographic Experts Group (JPEG) was formed to create a new standard, named the JPEG standard, that used data compression to keep graphics files small. The JPEG standard works by averaging colour variation and discarding what the human eye cannot see, a process known as “lossy” compression. Depending on the level of compression, it is possible to compress an image by a factor of 100 to 1, though there may be some loss of quality at the compression limits. Factors of 20 to 1 are easily done, however, and the loss of quality is practically invisible to the human eye. In comparison, the loss-less graphics interchange format ( GIF) only compresses by about 4 to 1.

      JPEGs are used primarily on the World Wide Web and in digital cameras (digital camera). Progressive JPEGs, a specific type of JPEG that initially shows a low-quality image that improves over a few passes, are especially useful for Internet users with slower connections. Many digital cameras store images as JPEGs, allowing more pictures to fit on a memory card, though cameras aimed at more-serious photographers can store uncompressed images, which retain more detail. JPEG files also have the ability to carry exchangeable image file format (EXIF) information that stores details about when a picture was taken and even settings such as exposure and shutter speed.

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Universalium. 2010.

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Look at other dictionaries:

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  • .jpeg — File Interchange Format JPEG File Interchange Format Extension de fichier .jpeg, .jpg, .jpe, .jfif, .jfi Type MIME image/jpeg Développé par Joint Photographic Experts Group Type de format format d’image matriciel avec perte …   Wikipédia en Français

  • Jpeg-ls — (souvent surnommé Lossless JPEG) est une norme de compression sans perte (donc réversible), basée sur l algorithme LOCO I (LOw COmplexity LOssless COmpression for Images) et évaluée par le Joint Photographic Experts Group, dont la notoriété est… …   Wikipédia en Français

  • JPEG-LS — (souvent surnommé Lossless JPEG) est une norme de compression sans perte (donc réversible), basée sur l algorithme LOCO I (LOw COmplexity LOssless COmpression for Images) et évaluée par le Joint Photographic Experts Group, dont la notoriété est… …   Wikipédia en Français

  • JPEG XR — (connu précédemment sous le nom Windows Media Photo et HD Photo) est un format graphique bitmap comprenant un algorithme de compression, créé par Microsoft. Il permet la compression avec perte ou sans perte. Il a été examiné et adopté comme… …   Wikipédia en Français

  • JPEG XR — Расширение .jxr[1], .hdp[2], .wdp[2] MIME image/vnd.ms photo Разработан JPEG Microsoft Опубликован …   Википедия

  • JPEG —   [sprich dschäipäg; Abk. für Joint Photographic Expert Group, dt. »vereinigte Fotoexpertengruppe«], internationales Forum zur Schaffung von Normen im Bereich der digitalen Bildspeicherung, die Mitglieder stammen aus nationalen Normungsbehörden… …   Universal-Lexikon

  • JPEG XR — (antes llamado Windows Media Photo y HD Photo) es un formato gráfico creado y adoptado por Microsoft. Este nuevo formato de codificación de imágenes fijas ofrece mayor calidad en menor tamaño que el formato JPEG. La reducción puede alcanzar hasta …   Wikipedia Español

  • JPEG — (Joint Photographic Experts Group) es un algoritmo diseñado para comprimir imágenes con 24 bits de profundidad o en escala de grises. JPEG es también el formato de fichero que utiliza este algoritmo para comprimir imágenes. JPEG sólo trata… …   Enciclopedia Universal

  • JPEG — n. [Acronym from Joint Picture Experts Group.] (Computers) A standardized format for storing graphic data in binary computer files, allowing over 16 million different colors. It allows for lossy compression, i. e. the compression of data into a… …   The Collaborative International Dictionary of English

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