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Region Of Interest
A region of interest (often abbreviated ROI) is a sample within a data set identified for a particular purpose. The concept of a ROI is commonly used in many application areas. Existing as a vicinity, or within one. For example, in medical imaging, the boundaries of a tumor may be defined on an image or in a volume, for the purpose of measuring its size. The endocardial border may be defined on an image, perhaps during different phases of the cardiac cycle, for example, end-systole and end-diastole, for the purpose of assessing cardiac function. In geographical information systems (GIS), a ROI can be taken literally as a polygonal selection from a 2D map. In computer vision and optical character recognition, the ROI defines the edge detection, borders of an object under consideration. In many applications, symbolic (textual) labels are added to a ROI, to describe its content in a compact manner. Within a ROI may lie individual ''point of interest, points of interest'' (POIs). Exam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Markov Inequality
In probability theory, Markov's inequality gives an upper bound on the probability that a non-negative random variable is greater than or equal to some positive constant. Markov's inequality is tight in the sense that for each chosen positive constant, there exists a random variable such that the inequality is in fact an equality. It is named after the Russian mathematician Andrey Markov, although it appeared earlier in the work of Pafnuty Chebyshev (Markov's teacher), and many sources, especially in analysis, refer to it as Chebyshev's inequality (sometimes, calling it the first Chebyshev inequality, while referring to Chebyshev's inequality as the second Chebyshev inequality) or Bienaymé's inequality. Markov's inequality (and other similar inequalities) relate probabilities to expectations, and provide (frequently loose but still useful) bounds for the cumulative distribution function of a random variable. Markov's inequality can also be used to upper bound the expectation o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fiducial Marker
A fiducial marker or fiducial is an object placed in the field of view of an image for use as a point of reference or a measure. It may be either something placed into or on the imaging subject, or a mark or set of marks in the reticle of an optical instrument. Applications Microscopy In high-resolution optical microscopy, fiducials can be used to actively stabilize the field of view. Stabilization to better than 0.1 nm is achievable. Physics In physics, 3D computer graphics, and photography, fiducials are reference points: fixed points or lines within a scene to which other objects can be related or against which objects can be measured. Cameras outfitted with Réseau plates produce these reference marks (also called Réseau crosses) and are commonly used by NASA. Such marks are closely related to the timing marks used in optical mark recognition. Geographical survey Airborne geophysics, geophysical surveys also use the term "fiducial" as a sequential reference number ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Imaging
Medical imaging is the technique and process of imaging the interior of a body for clinical analysis and medical intervention, as well as visual representation of the function of some organs or tissues (physiology). Medical imaging seeks to reveal internal structures hidden by the skin and bones, as well as to diagnose and treat disease. Medical imaging also establishes a database of normal anatomy and physiology to make it possible to identify abnormalities. Although imaging of removed organ (anatomy), organs and Tissue (biology), tissues can be performed for medical reasons, such procedures are usually considered part of pathology instead of medical imaging. Measurement and recording techniques that are not primarily designed to produce images, such as electroencephalography (EEG), magnetoencephalography (MEG), electrocardiography (ECG), and others, represent other technologies that produce data susceptible to representation as a parameter graph versus time or maps that contain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JPEG 2000
JPEG 2000 (JP2) is an image compression standard and coding system. It was developed from 1997 to 2000 by a Joint Photographic Experts Group committee chaired by Touradj Ebrahimi (later the JPEG president), with the intention of superseding their original JPEG standard (created in 1992), which is based on a discrete cosine transform (DCT), with a newly designed, wavelet-based method. The standardized filename extension is .jp2 for International Organization for Standardization, ISO/International Electrotechnical Commission, IEC 15444-1 conforming files and .jpx for the extended part-2 specifications, published as ISO/IEC 15444-2. The Internet media type, MIME types for JPEG 2000 are defined in RFC 3745. The MIME type for JPEG 2000 (ISO/IEC 15444-1) is image/jp2. The JPEG 2000 project was motivated by Ricoh, Ricoh's submission in 1995 of the CREW (Compression with Reversible Embedded Wavelets) algorithm to the standardization effort of JPEG LS. Ultimately the Lossless JPEG#LOCO-I_a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VRML
VRML (Virtual Reality Modeling Language, pronounced ''vermal'' or by its initials, originally—before 1995—known as the Virtual Reality Markup Language) is a standard file format for representing 3-dimensional (3D) interactive vector graphics, designed particularly with the World Wide Web in mind. It has been superseded by X3D. WRL file format VRML is a text file format where, e.g., vertices and edges for a 3D polygon can be specified along with the surface color, UV-mapped textures, shininess, transparency, and so on. URLs can be associated with graphical components so that a web browser might fetch a webpage or a new VRML file from the Internet when the user clicks on the specific graphical component. Animations, sounds, lighting, and other aspects of the virtual world can interact with the user or may be triggered by external events such as timers. A special Script Node allows the addition of program code (e.g., written in Java or ECMAScript) to a VRML file. V ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scalable Vector Graphics
Scalable Vector Graphics (SVG) is an XML-based vector graphics format for defining two-dimensional graphics, having support for interactivity and animation. The SVG specification is an open standard developed by the World Wide Web Consortium since 1999. SVG images are defined in a vector graphics format and stored in XML text files. SVG images can thus be scaled in size without loss of quality, and SVG files can be searched, indexed, scripted, and compressed. The XML text files can be created and edited with text editors or vector graphics editors, and are rendered by most web browsers. If used for images, SVG can host scripts or CSS, potentially leading to cross-site scripting attacks or other security vulnerabilities. History SVG has been in development within the World Wide Web Consortium (W3C) since 1999 after six competing proposals for vector graphics languages had been submitted to the consortium during 1998 (see below). The early SVG Working Group decided not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PostScript
PostScript (PS) is a page description language and dynamically typed, stack-based programming language. It is most commonly used in the electronic publishing and desktop publishing realm, but as a Turing complete programming language, it can be used for many other purposes as well. PostScript was created at Adobe Systems by John Warnock, Charles Geschke, Doug Brotz, Ed Taft and Bill Paxton from 1982 to 1984. The most recent version, PostScript 3, was released in 1997. History The concepts of the PostScript language were seeded in 1976 by John Gaffney at Evans & Sutherland, a computer graphics company. At that time, Gaffney and John Warnock were developing an interpreter for a large three-dimensional graphics database of New York Harbor. Concurrently, researchers at Xerox PARC had developed the first laser printer and had recognized the need for a standard means of defining page images. In 1975–76 Bob Sproull and William Newman developed the Press format, whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Document Layout Analysis
In computer vision or natural language processing, document layout analysis is the process of identifying and categorizing the regions of interest in the scanned image of a text document. A reading system requires the segmentation of text zones from non-textual ones and the arrangement in their correct reading order. Detection and labeling of the different zones (or blocks) as text body, illustrations, math symbols, and tables embedded in a document is called geometric layout analysis. But text zones play different logical roles inside the document (titles, captions, footnotes, etc.) and this kind of semantic labeling is the scope of the logical layout analysis. Document layout analysis is the union of geometric and logical labeling. It is typically performed before a document image is sent to an OCR engine, but it can be used also to detect duplicate copies of the same document in large archives, or to index documents by their structure or pictorial content. Document layout is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Character Recognition
Optical character recognition or optical character reader (OCR) is the electronics, electronic or machine, mechanical conversion of images of typed, handwritten or printed text into machine-encoded text, whether from a scanned document, a photo of a document, a scene photo (for example the text on signs and billboards in a landscape photo) or from subtitle text superimposed on an image (for example: from a television broadcast). Widely used as a form of data entry from printed paper data recordswhether passport documents, invoices, bank statements, computerized receipts, business cards, mail, printed data, or any suitable documentationit is a common method of digitizing printed texts so that they can be electronically edited, searched, stored more compactly, displayed online, and used in machine processes such as cognitive computing, machine translation, (extracted) text-to-speech, key data and text mining. OCR is a field of research in pattern recognition, artificial intelligen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JPEG
JPEG ( , short for Joint Photographic Experts Group and sometimes retroactively referred to as JPEG 1) is a commonly used method of lossy compression for digital images, particularly for those images produced by digital photography. The degree of compression can be adjusted, allowing a selectable trade off between storage size and image quality. JPEG typically achieves 10:1 compression with noticeable, but widely agreed to be acceptable perceptible loss in image quality. Since its introduction in 1992, JPEG has been the most widely used image compression standard in the world, and the most widely used digital image format, with several billion JPEG images produced every day as of 2015. The Joint Photographic Experts Group created the standard in 1992, based on the discrete cosine transform (DCT) algorithm. JPEG was largely responsible for the proliferation of digital images and digital photos across the Internet and later social media. JPEG compression is used in a number of ... [...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] |
Polyline
In geometry, a polygonal chain is a connected series of line segments. More formally, a polygonal chain is a curve specified by a sequence of points (A_1, A_2, \dots, A_n) called its vertices. The curve itself consists of the line segments connecting the consecutive vertices. Variations Simple A simple polygonal chain is one in which only consecutive segments intersect and only at their endpoints. Closed A closed polygonal chain is one in which the first vertex coincides with the last one, or, alternatively, the first and the last vertices are also connected by a line segment. A simple closed polygonal chain in the plane is the boundary of a simple polygon. Often the term "polygon" is used in the meaning of "closed polygonal chain", but in some cases it is important to draw a distinction between a polygonal area and a polygonal chain. A space closed polygonal chain is also known as a skew "polygon". Monotone A polygonal chain is called ''monotone'' if there is a straig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
