The point features are recorded as single x and y pair of coordinates. In the vector data, the spatial information are recorded as x, y coordinates. Vector models are useful for storing data that has discrete boundaries, such as country borders, land parcels, and streets. Vector Data: A representation of the world using points, lines, and polygons. Projection transformations are time consuming and difficult.Network linkages are difficult to establish.The raster maps are considerably less beautiful than line maps.The use of large cells to reduce data volumes means that phenomenologically recognizable structures can be lost and there can be a serious loss of information.Overlay analysis is easy to perform with raster model.Continuous features are best represented using raster.Compatible with remotely sensed imagery.The rows of the matrix are parallel to X – axis and the columns are parallel to the Y-axis. Pixel or cell are arranged in rows and columns that construct a certain matrix format. A pixel or cell represent a square kilometer, a square meter or even a square centimeter. The pixel can be any size, but they should be small enough to perform maximum detail analysis. This type of spatial data usually bulky and required large storage capacity.Įxample of raster data as satellite imagery, digital elevation model (DEM), aerial photography, Scanned maps etc.Īll pixels in a raster data must be the same size, determining the resolution. Each pixel preserves locational information. It is represented by matrix or grid of pixel. Raster data comes in the form of individual pixels. Thus the attribute is represented as a single value of each pixel or cell that is called as DN (Digital Number Value). When the data is geo-referenced the data give each and every pixel its locational information. The raster data are the data that have individual pixels where each pixel has its spatial location in referenced to real earth. Raster Data: A raster consists of a matrix of cells (or pixels) organized into rows and columns (or a grid) where each cell contains a value representing information, such as temperature. The non-spatial data can be two types Statistical which have numerical value and Descriptive that are stored in the form of word or text. These types are also known as attribute data.įor instance, if the spatial data contain a polygon representing a state, than in attribute data it has information about its administrative division like area, population etc. While on the other hand non-spatial data are those representing a set of information that is systematically organized and computing against spatial data. The spatial data further divided into two types Raster data and Vector data. It represents the location of geographical entities as well as spatial dimension that are represented with the help of point, line and polygon/area. Spatial data are those that have coordinates: latitudinal and longitudinal that shows position of feature. GIS Data Types: There are two types of data are used in GIS platform that is, spatial data and non-spatial data. PDF DOWNLOAD LINK IN THE BOTTOM OF THIS POST RASTER DATA & VECTOR DATA IN REMOTE SENSING & GIS
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