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Minimum Bounding Rectangle
In computational geometry, the minimum bounding rectangle (MBR), also known as bounding box (BBOX) or envelope, is an expression of the maximum extents of a two-dimensional object (e.g. point, line, polygon) or set of objects within its coordinate system; in other words , , , {{math, max(''y''). The MBR is a 2-dimensional case of the minimum bounding box. MBRs are frequently used as an indication of the general position of a geographic feature or dataset, for either display, first-approximation spatial query, or spatial indexing purposes. The degree to which an "overlapping rectangles" query based on MBRs will be satisfactory (in other words, produce a low number of " false positive" hits) will depend on the extent to which individual spatial objects occupy (fill) their associated MBR. If the MBR is full or nearly so (for example, a mapsheet aligned with axes of latitude and longitude will normally entirely fill its associated MBR in the same coordinate space), then the " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geospatial Metadata
Geospatial metadata (also geographic metadata) is a type of metadata applicable to geographic data and information. Such objects may be stored in a geographic information system (GIS) or may simply be documents, data-sets, images or other objects, services, or related items that exist in some other native environment but whose features may be appropriate to describe in a (geographic) metadata catalog (may also be known as a data directory or data inventory). Definition ISO 19115:2013 "Geographic Information – Metadata" from ISO/TC 211, the industry standard for geospatial metadata, describes its scope as follows: ISO 19115:2013 also provides for non-digital mediums: The U.S. Federal Geographic Data Committee (FGDC) describes geospatial metadata as follows: History The growing appreciation of the value of geospatial metadata through the 1980s and 1990s led to the development of a number of initiatives to collect metadata according to a variety of formats either within age ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minimum Bounding Box
In geometry, the minimum bounding box or smallest bounding box (also known as the minimum enclosing box or smallest enclosing box) for a point set in dimensions is the box with the smallest measure (area, volume, or hypervolume in higher dimensions) within which all the points lie. When other kinds of measure are used, the minimum box is usually called accordingly, e.g., "minimum-perimeter bounding box". The minimum bounding box of a point set is the same as the minimum bounding box of its convex hull, a fact which may be used heuristically to speed up computation. In the two-dimensional case it is called the ''minimum bounding rectangle''. Axis-aligned minimum bounding box The axis-aligned minimum bounding box (or AABB) for a given point set is its minimum bounding box subject to the constraint that the edges of the box are parallel to the (Cartesian) coordinate axes. It is the Cartesian product of ''N'' intervals each of which is defined by the minimal and maximal value o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Largest Empty Rectangle
In computational geometry, the largest empty rectangle problem, maximal empty rectangle problem or maximum empty rectangle problem, is the problem of finding a rectangle of maximal size to be placed among obstacles in the plane. There are a number of variants of the problem, depending on the particularities of this generic formulation, in particular, depending on the measure of the "size", domain (type of obstacles), and the orientation of the rectangle. The problems of this kind arise e.g., in electronic design automation, in design and verification of physical layout of integrated circuits. A maximal empty rectangle is a rectangle which is not contained in another empty rectangle. Each side of a maximal empty rectangle abuts an obstacle (otherwise the side may be shifted outwards, increasing the empty rectangle). An application of this kind is enumeration of "maximal white rectangles" in image segmentation R&D of image processing and pattern recognition. In the contexts of man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geospatial Metadata
Geospatial metadata (also geographic metadata) is a type of metadata applicable to geographic data and information. Such objects may be stored in a geographic information system (GIS) or may simply be documents, data-sets, images or other objects, services, or related items that exist in some other native environment but whose features may be appropriate to describe in a (geographic) metadata catalog (may also be known as a data directory or data inventory). Definition ISO 19115:2013 "Geographic Information – Metadata" from ISO/TC 211, the industry standard for geospatial metadata, describes its scope as follows: ISO 19115:2013 also provides for non-digital mediums: The U.S. Federal Geographic Data Committee (FGDC) describes geospatial metadata as follows: History The growing appreciation of the value of geospatial metadata through the 1980s and 1990s led to the development of a number of initiatives to collect metadata according to a variety of formats either within age ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geographic Information System
A geographic information system (GIS) consists of integrated computer hardware and Geographic information system software, software that store, manage, Spatial analysis, analyze, edit, output, and Cartographic design, visualize Geographic data and information, geographic data. Much of this often happens within a spatial database; however, this is not essential to meet the definition of a GIS. In a broader sense, one may consider such a system also to include human users and support staff, procedures and workflows, the Geographic Information Science and Technology Body of Knowledge, body of knowledge of relevant concepts and methods, and institutional organizations. The uncounted plural, ''geographic information systems'', also abbreviated GIS, is the most common term for the industry and profession concerned with these systems. The academic discipline that studies these systems and their underlying geographic principles, may also be abbreviated as GIS, but the unambiguous GIScie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elongatedness
In image processing, elongatedness for a region is the ratio between the length and width of the minimum bounding rectangle of the region. It is considered a Feature (computer vision), feature of the region. It can be evaluated as the ratio between the area of the region to its thickness squared: elongatedness = \frac = \frac. where the maximum thickness, d, of a holeless region is given by the number of times the region can be Erosion (morphology), eroded before disappearing. References {{Reflist Image processing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Darboux Integral
In real analysis, the Darboux integral is constructed using Darboux sums and is one possible definition of the integral of a function. Darboux integrals are equivalent to Riemann integrals, meaning that a function is Darboux-integrable if and only if it is Riemann-integrable, and the values of the two integrals, if they exist, are equal. The definition of the Darboux integral has the advantage of being easier to apply in computations or proofs than that of the Riemann integral. Consequently, introductory textbooks on calculus and real analysis often develop Riemann integration using the Darboux integral, rather than the true Riemann integral. Moreover, the definition is readily extended to defining Riemann–Stieltjes integration. Darboux integrals are named after their inventor, Gaston Darboux (1842–1917). Definition The definition of the Darboux integral considers upper and lower (Darboux) integrals, which exist for any bounded real-valued function f on the interval ,b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C-squares
C-squares (acronym for the ''Concise Spatial QUery And REpresentation System'') is a system of spatially unique, location-based identifiers (geocodes) for areas on the surface of the earth, represented as cells from a latitude- and longitude-based Discrete Global Grid at a hierarchical set of resolution steps, obtained by progressively subdividing 10×10 degree World Meteorological Organization squares; the term "c-square" is also available for use to designate any component cell of the grid. Individual cell identifiers incorporate literal values of latitude and longitude in an interleaved notation (producing grid resolutions of 10, 1, 0.1 Decimal degrees, degrees, etc.), together with additional digits that support intermediate grid resolutions of 5, 0.5, 0.05 degrees, etc. The system was initially designed to represent data "footprints" or spatial extents in a more flexible manner than a standard minimum bounding rectangle, and to support "lightweight", text-based Spatial datab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conjugate Diameters
In geometry, two diameters of a conic section are said to be conjugate if each chord (geometry), chord parallel (geometry), parallel to one diameter is bisection, bisected by the other diameter. For example, two diameters of a circle are conjugate if and only if they are perpendicular. Of ellipse For an ellipse, two diameters are conjugate if and only if the tangent line to the ellipse at an endpoint of one diameter is parallel to the other diameter. Each pair of conjugate diameters of an ellipse has a corresponding tangent parallelogram, sometimes called a bounding parallelogram (skewed compared to a bounding rectangle). In his manuscript De motu corporum in gyrum, and in the 'Philosophiæ Naturalis Principia Mathematica, Principia', Isaac Newton cites as a lemma (mathematics), lemma proved by previous authors that all (bounding) parallelograms for a given ellipse have the same area. It is possible to Compass and straightedge constructions, reconstruct an ellipse from any pai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Open Geospatial Consortium
The Open Geospatial Consortium (OGC) is an international voluntary consensus standards organization that develops and maintains international standards for geospatial content and location-based services, sensor web, Internet of Things, Geographic Information System, GIS data processing and data sharing. The OGC was incorporated as a not for profit in 1994. At that time, the official name was the OpenGIS Consortium. It is a U.S.-registered 501c(6) non-profit with offices in Belgium and the U.K. Commercial, government, nonprofit, universities, and research organizations from around the world participate in a consensus process encouraging development, maintenance, and implementation of open standards. History A predecessor organization, OGF, the Open GRASS GIS, GRASS Foundation, started in 1992. From 1994 to 2004 the organization used the name OpenGIS Consortium. The OGC website gives a detailed history of the OGC. Standards Most of the OGC Standards depend on a generalized arc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geography Markup Language
The Geography Markup Language (GML) is the XML grammar defined by the Open Geospatial Consortium (OGC) to express geographical features. GML serves as a modeling language for geographic systems as well as an open interchange format for geographic transactions on the Internet. Key to GML's utility is its ability to integrate all forms of geographic information, including not only conventional "vector" or discrete objects, but coverages (see also GMLJP2) and sensor data. GML model GML contains a rich set of primitives which are used to build application specific schemas or application languages. These primitives include: * Feature * Geometry * Coordinate reference system * Topology * Time * Dynamic feature * Coverage (including geographic images) * Unit of measure * Directions * Observations * Map presentation styling rules The original GML model was based on the World Wide Web Consortium's Resource Description Framework (RDF). Subsequently, the OGC introduced XML schemas int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
