What is the raster gis?
Geographic Information System (GIS) is a computer system that processes various forms of data engaged in advanced mapping. Among other things, it may collect, store and analyze data for use in various fields such as urban planning and archeology. GIS based on raster or simply raster GIS uses a combination of cartographic and frame data to provide complete representation of the studied area. The grid is used to represent image data and calculations can be done using data to reveal the relationships between the attributes of the target area. Raster GIS is commonly used to classify vegetation, use of land and changes in cities in a particular area. Such systems are good for representing data that can be measured at any point, such as temperature and increase. Information about recording raster cells on the interior of cells and borders is created cells.
gis -based raster representData sets by distributing the map into the same size cells aligned in the grid. Cells can be assigned a value used to represent a certain characteristic regarding the location and all cells of one set of data form a layer or grid. The layer and cell format of the GIS data set allows you to locate multiple data in the same location. When the layers are stacked, relationships that occupy the same cell are formed between different data sets. The ability to compare relationships in different cells of a given area is what makes raster GIS with such a useful tool.
GIS technician can use covered GIS raster layers to create new layers using algebraic equations. Algebraic equations or map algebers allow you to create new layers using GIS information to eliminate soil areas that do not meet user -definted criteria. The ability to compose layers of information makes raster GIS a good tool for identifying websites that meet specific requirements.
Progress in years technologyADEL and satellite technologies have made it possible to improve the ability and easy use of remote sensing to collect GIS raster data. The remote survey tools are fixed to aircraft and satellites and from there they collect different types of images. Remote survey tools can detect and record visible data as well as any measurable part of the electromagnetic spectrum.
The disadvantage of this system is that linear functions such as rivers are difficult to represent. The size of the cell determines how accurate boundaries and features are displayed. A smaller cell allows more accurate limits, but requires more data processing.