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Color Quantization
In computer graphics, color quantization or color image quantization is quantization applied to color spaces; it is a process that reduces the number of distinct colors used in an image, usually with the intention that the new image should be as visually similar as possible to the original image. Computer algorithms to perform color quantization on bitmaps have been studied since the 1970s. Color quantization is critical for displaying images with many colors on devices that can only display a limited number of colors, usually due to memory limitations, and enables efficient compression of certain types of images. The name "color quantization" is primarily used in computer graphics research literature; in applications, terms such as ''optimized palette generation'', ''optimal palette generation'', or ''decreasing color depth'' are used. Some of these are misleading, as the palettes generated by standard algorithms are not necessarily the best possible. Algorithms Most standar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dithering Example Undithered
Dither is an intentionally applied form of image noise, noise used to randomize quantization error, preventing large-scale patterns such as color banding in images. Dither is routinely used in processing of both digital audio and digital video, video data, and is often one of the last stages of Audio mastering, mastering audio to a CD. A common use of dither is converting a grayscale image to Binary image, black and white, so that the density of black dots in the new image approximates the average gray level in the original. Etymology The term ''dither'' was published in books on analog computation and hydraulically controlled guns shortly after World War II. Though he did not use the term ''dither'', the concept of dithering to reduce quantization patterns was first applied by Lawrence G. Roberts in his 1961 MIT master's thesis and 1962 article. By 1964 dither was being used in the modern sense described in this article. The technique was in use at least as early as 1915, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rosa Gold Glow 2 Small Noblue Color Space
Rosa or De Rosa may refer to: Plants and animals * ''Rosa'' (plant), the genus of roses * Rosa (sea otter), a sea otter that has become popular on the internet * Rosa (cow), a Spanish-born cow People * Rosa (given name) * Rosa (surname) * Santa Rosa (female given name from Latin-a latinized variant of Rose) Places * 223 Rosa, an asteroid * Rosa, Alabama, a town, United States * Rosa, Germany, in Thuringia, Germany *Rösa, a village and former municipality in Saxony-Anhalt, Germany * Rosà a town in the province of Vicenza, Veneto, Italy *Monte Rosa, the second highest mountain in the Alps and Western Europe *Republic of South Africa, a southernmost country in Africa. Film and television * ''Rosa'' (1986 film), a Hong Kong film released by Bo Ho Films *'' Rosa – A Horse Drama'', a 1993-94 opera by Louis Andriessen on a libretto by Peter Greenaway * "Rosa" (''Doctor Who''), an episode of the eleventh series of ''Doctor Who'' Music *"Rosa", a song by Pixinguinha *De Rosa (ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indexed Color
In computing, indexed color is a technique to manage digital images' colors in a limited fashion, in order to save computer computer data storage, memory and Hard disk drive, file storage, while speeding up display refresh and file transfers. It is a form of Vector quantization#Use in data compression, vector quantization compression. When an image is encoding, encoded in this way, color information is not directly carried by the image pixel data, but is stored in a separate piece of data called a color lookup table (CLUT) or Palette (computing), palette: an array of color specifications. Every element in the array represents a color, indexed by its position within the array. Each image pixel does not contain the full specification of its color, but only its index into the ''palette''. This technique is sometimes referred as pseudocolor or indirect color, as colors are addressed indirectly. History Early graphics display systems that used 8-bit indexed color with frame buffers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Web Colors
Web colors are colors used in Web design, displaying web pages on the World Wide Web; they can be described by way of three methods: a color may be specified as an RGB color model, RGB triplet, in hexadecimal format (a ''hex triplet'') or according to its common English name in some cases. A color tool or other graphics software is often used to generate color values. In some uses, hexadecimal color codes are specified with notation using a leading number sign (#). A color is specified according to the intensity of its red, green and blue components, each represented by eight bits. Thus, there are 24 bits used to specify a web color within the sRGB gamut, and 16,777,216 colors that may be so specified. Colors outside the sRGB gamut can be specified in CSS, Cascading Style Sheets by making one or more of the red, green and blue components negative or greater than 100%, so the color space is theoretically an unbounded extrapolation of sRGB similar to scRGB. Specifying a non-sRGB ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World Wide Web
The World Wide Web (WWW or simply the Web) is an information system that enables Content (media), content sharing over the Internet through user-friendly ways meant to appeal to users beyond Information technology, IT specialists and hobbyists. It allows documents and other web resources to be accessed over the Internet according to specific rules of the HTTP, Hypertext Transfer Protocol (HTTP). The Web was invented by English computer scientist Tim Berners-Lee while at CERN in 1989 and opened to the public in 1993. It was conceived as a "universal linked information system". Documents and other media content are made available to the network through web servers and can be accessed by programs such as web browsers. Servers and resources on the World Wide Web are identified and located through character strings called uniform resource locators (URLs). The original and still very common document type is a web page formatted in Hypertext Markup Language (HTML). This markup lang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portable Network Graphics
Portable Network Graphics (PNG, officially pronounced , colloquially pronounced ) is a raster graphics, raster-graphics file graphics file format, format that supports lossless data compression. PNG was developed as an improved, non-patented replacement for Graphics Interchange Format (GIF). PNG supports palette-based images (with palettes of 24-bit RGB color model, RGB or 32-bit RGBA color space, RGBA colors), grayscale images (with or without an Alpha compositing, alpha channel for transparency), and full-color non-palette-based RGB or RGBA images. The PNG working group designed the format for transferring images on the Internet, not for professional-quality print graphics; therefore, non-RGB color spaces such as CMYK color model, CMYK are not supported. A PNG file contains a single image in an extensible structure of ''chunks'', encoding the basic pixels and other information such as textual comments and Integrity checker, integrity checks documented in Request for Comments ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Bonn
The University of Bonn, officially the Rhenish Friedrich Wilhelm University of Bonn (), is a public research university in Bonn, North Rhine-Westphalia, Germany. It was founded in its present form as the () on 18 October 1818 by Frederick William III, as the linear successor of the () which was founded in 1777. The University of Bonn offers many undergraduate and graduate programs in a range of subjects and has 544 professors. The University of Bonn is a member of the U15 (German universities), German U15 association of major research-intensive universities in Germany and has the title of "University of Excellence" under the German Universities Excellence Initiative. Bonn has 6 Clusters of Excellence, the most of any German university; the Hausdorff Center for Mathematics, the Matter and Light for Quantum Computing cluster, Bonn Center for Dependency and Slavery Studies, PhenoRob: Research for the Future of Crop Production, the Immune Sensory System cluster, and ECONtribute: M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-organizing Map
A self-organizing map (SOM) or self-organizing feature map (SOFM) is an unsupervised machine learning technique used to produce a low-dimensional (typically two-dimensional) representation of a higher-dimensional data set while preserving the topological structure of the data. For example, a data set with p variables measured in n observations could be represented as clusters of observations with similar values for the variables. These clusters then could be visualized as a two-dimensional "map" such that observations in proximal clusters have more similar values than observations in distal clusters. This can make high-dimensional data easier to visualize and analyze. An SOM is a type of artificial neural network but is trained using competitive learning rather than the error-correction learning (e.g., backpropagation with gradient descent) used by other artificial neural networks. The SOM was introduced by the Finnish professor Teuvo Kohonen in the 1980s and therefore is some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ada Lovelace
Augusta Ada King, Countess of Lovelace (''née'' Byron; 10 December 1815 – 27 November 1852), also known as Ada Lovelace, was an English mathematician and writer chiefly known for her work on Charles Babbage's proposed mechanical general-purpose computer, the Analytical Engine. She was the first to recognise that the machine had applications beyond pure calculation. Lovelace was the only legitimate child of poet Lord Byron and reformer Anne Isabella Milbanke. All her half-siblings, Lord Byron#Children, Lord Byron's other children, were born out of wedlock to other women. Lord Byron separated from his wife a month after Ada was born and left England forever. He died in Greece when she was eight. Lady Byron was anxious about her daughter's upbringing and promoted Lovelace's interest in mathematics and logic in an effort to prevent her from developing her father's perceived insanity. Despite this, Lovelace remained interested in her father, naming her two sons Byron King-Noel, V ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Image And Vision Computing
An image or picture is a visual representation. An image can be two-dimensional, such as a drawing, painting, or photograph, or three-dimensional, such as a carving or sculpture. Images may be displayed through other media, including a projection on a surface, activation of electronic signals, or digital displays; they can also be reproduced through mechanical means, such as photography, printmaking, or photocopying. Images can also be animated through digital or physical processes. In the context of signal processing, an image is a distributed amplitude of color(s). In optics, the term ''image'' (or ''optical image'') refers specifically to the reproduction of an object formed by light waves coming from the object. A ''volatile image'' exists or is perceived only for a short period. This may be a reflection of an object by a mirror, a projection of a camera obscura, or a scene displayed on a cathode-ray tube. A ''fixed image'', also called a hard copy, is one that has been r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
K-means Clustering
''k''-means clustering is a method of vector quantization, originally from signal processing, that aims to partition of a set, partition ''n'' observations into ''k'' clusters in which each observation belongs to the cluster (statistics), cluster with the nearest mean (cluster centers or cluster centroid), serving as a prototype of the cluster. This results in a partitioning of the data space into Voronoi cells. ''k''-means clustering minimizes within-cluster variances (squared Euclidean distances), but not regular Euclidean distances, which would be the more difficult Weber problem: the mean optimizes squared errors, whereas only the geometric median minimizes Euclidean distances. For instance, better Euclidean solutions can be found using k-medians clustering, ''k''-medians and k-medoids, ''k''-medoids. The problem is computationally difficult (NP-hardness, NP-hard); however, efficient heuristic algorithms converge quickly to a local optimum. These are usually similar to the ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dither
Dither is an intentionally applied form of noise used to randomize quantization error, preventing large-scale patterns such as color banding in images. Dither is routinely used in processing of both digital audio and video data, and is often one of the last stages of mastering audio to a CD. A common use of dither is converting a grayscale image to black and white, so that the density of black dots in the new image approximates the average gray level in the original. Etymology The term ''dither'' was published in books on analog computation and hydraulically controlled guns shortly after World War II. Though he did not use the term ''dither'', the concept of dithering to reduce quantization patterns was first applied by Lawrence G. Roberts in his 1961 MIT master's thesis and 1962 article. By 1964 dither was being used in the modern sense described in this article. The technique was in use at least as early as 1915, though not under the name ''dither''. In digital pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
