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In digital imaging, a pixel, pel, or picture element is a physical point in a raster image, or the smallest addressable element in an all points addressable display device; so it is the smallest controllable element of a picture represented on the screen. The address of a pixel corresponds to its physical coordinates. LCD pixels are manufactured in a two-dimensional grid, and are often represented using dots or squares, but CRT pixels correspond to their timing mechanisms and sweep rates. Each pixel is a sample of an original image; more samples typically provide more accurate representations of the original. The intensity of each pixel is variable. In color image systems, a color is typically represented by three or four component intensities such as red, green, and blue, or cyan, magenta, yellow, and black. In some contexts (such as descriptions of camera sensors), the term ''pixel'' is used to refer to a single scalar element of a multi-component representation (more precisely called a ''photosite'' in the camera sensor context, although the neologism ''sensel'' is sometimes used to describe the elements of a digital camera's sensor), while in others the term may refer to the entire set of such component intensities for a spatial position. In color systems that use chroma subsampling, the multi-component concept of a pixel can become difficult to apply, since the intensity measures for the different color components correspond to different spatial areas in such a representation. The word ''pixel'' is based on a contraction of ''pix'' (from word "pictures", where it is shortened to "pics", and "cs" in "pics" sounds like "x") and ''el'' (for "element"); similar formations with ''el'' for "element" include the words voxel and texel.〔 == Etymology == The word "pixel" was first published in 1965 by Frederic C. Billingsley of JPL, to describe the picture elements of video images from space probes to the Moon and Mars.〔Fred C. Billingsley, "Processing Ranger and Mariner Photography," in ''Computerized Imaging Techniques, Proceedings of SPIE'', Vol. 0010, pp. XV-1–19, Jan. 1967 (Aug. 1965, San Francisco).〕 However, Billingsley did not coin the term himself. Instead, he got the word "pixel" from Keith E. McFarland, at the Link Division of General Precision in Palo Alto, who did not know where the word originated. McFarland said simply it was "in use at the time" (circa 1963).〔Lyon, Richard F. (2006). (A brief history of 'pixel' ). IS&T/SPIE Symposium on Electronic Imaging.〕 The word is a combination of ''pix'', for picture, and ''element''. The word ''pix'' appeared in ''Variety'' magazine headlines in 1932, as an abbreviation for the word ''pictures'', in reference to movies. By 1938, "pix" was being used in reference to still pictures by photojournalists.〔 The concept of a "picture element" dates to the earliest days of television, for example as "''Bildpunkt''" (the German word for ''pixel'', literally 'picture point') in the 1888 German patent of Paul Nipkow. According to various etymologies, the earliest publication of the term ''picture element'' itself was in ''Wireless World'' magazine in 1927,〔("On language; Modem, I'm Odem" ), ''The New York Times'', April 2, 1995. Accessed April 7, 2008.〕 though it had been used earlier in various U.S. patents filed as early as 1911.〔Sinding-Larsen, Alf (Transmission of Pictures of Moving Objects ), US Patent 1,175,313, issued March 14, 1916.〕 Some authors explain ''pixel'' as ''picture cell,'' as early as 1972. In graphics and in image and video processing, ''pel'' is often used instead of ''pixel''.〔Lewis, Peter H. (February 12, 1989). (The Executive Computer; Compaq Sharpens Its Video Option ). ''The New York Times''.〕 For example, IBM used it in their Technical Reference for the original PC. Pixilation, spelled with a second ''i'', is an unrelated filmmaking technique that dates to the beginnings of cinema, in which live actors are posed frame by frame and photographed to create stop-motion animation. An archaic British word meaning "possession by spirits (pixies)," the term has been used to describe the animation process since the early 1950s; various animators, including Norman McLaren and Grant Munro, are credited with popularizing it.〔(Frame by Frame Stop Motion: NonTraditional Approaches to Stop Motion Animation - Tom Gasek - Google Books )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「pixel」の詳細全文を読む スポンサード リンク
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