GeoJSON comprises the seven concrete geometry types defined in the Geographic information system standards and have been streamlined toīetter suit web application development using JSON. In GeoJSON are not new they are derived from preexisting open The format is concerned with geographic data in the broadest sense Īnything with qualities that are bounded in geographical space mightīe a Feature whether or not it is a physical structure. Geometry object and additional properties, and a FeatureCollection Point, LineString, Polygon, MultiPoint, MultiLineString, GeoJSON supports the following geometry types: Spatially bounded entity (a Feature), or a list of Features (aįeatureCollection). GeoJSON object may represent a region of space (a Geometry), a Structures using JavaScript Object Notation (JSON). GeoJSON is a format for encoding a variety of geographic data Semantics of GeoJSON Members and Types Are Not Changeable 16Ĩ. The Trust Legal Provisions and are provided without warranty asġ. Include Simplified BSD License text as described in Section 4.e of Code Components extracted from this document must Please review these documentsĬarefully, as they describe your rights and restrictions with respect This document is subject to BCP 78 and the IETF Trust's Legal Information about the current status of this document, any errata,Īnd how to provide feedback on it may be obtained atĬopyright (c) 2016 IETF Trust and the persons identified as the Internet Standards is available in Section 2 of RFC 7841. Internet Engineering Steering Group (IESG). Received public review and has been approved for publication by the It represents the consensus of the IETF community. This document is a product of the Internet Engineering Task Force This is an Internet Standards Track document. System 1984, and units of decimal degrees. GeoJSON uses a geographic coordinate reference system, World Geodetic Geographic features, their properties, and their spatial extents. The manner in which they are combined to represent data about It defines several types of JSON objects and GeoJSON is a geospatial data interchange format based on JavaScript Point clouds may also store a 4x4 transformation matrix, which is applied to the x/y/z components.RFC 7946: The GeoJSON Format Įrrata Exist Internet Engineering Task Force (IETF) H. For example, point clouds typically have all of the x/y/z components, but a point cloud may not have z (making it 2D), or may not have any of x/y/z (making it non-spatial). Note that there are no required components. Values correspond to the ASPRS LAS specification. Indicates special characteristics associated with each point. Used to express the time, as the number of seconds elapsed since UTC January 1st, 1970.ĭata to be used at the user’s discretion. The direction in which a scanning mirror was directed when the point was detected.Ī value that indicates the source of the file, such as a file number. Whether this point lies on the edge of the scan, along the flight line. The flight line number the point was detected in. The angle of the pulse that the point was scanned at. The week number, counting from January 6th, 1980. The number of seconds since the beginning of the week. The total number of detected returns from a single pulse. The pulse return number for a given output pulse. Categorizes a point into fields, such as ground, building, water, and others. ![]() The blue image channel value at the point. The green image channel value at the point. ![]() The red image channel value at the point. The magnitude of the intensity of the pulse return. A point cloud may have any number of components not listed here. These components are described in the following table. While components may have any name, there are a few common components that exist in several formats. ![]() String components additionally may have an encoding. Numeric components additionally may have a scale and offset factor in such cases, the applied value of the component is value x scale + offset. Possible component types are Real64, Real32, UInt64, UInt32, UInt16, UInt8, Int64, Int32, Int16, Int8, and String. Note that all points in a point cloud have the same schema (that is, the same set of components), but each point may have a different value for each component.Īll components have a name and type. Components are similar to attributes, but at the point level instead of at the feature level. Point clouds are useful for storing large amounts of data, often gathered from LIDAR applications.Īssociated with each point are properties called components, which contain a value that describes the point. A point cloud geometry is a (potentially large) collection of points.
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