Geographic Information System (GIS) is computer software used to view and analyze spatial relationships between multiple types of maps and databases simultaneously. These datasets may include the details of utility infrastructure, landcover or even demographic information. Data used in GIS are categorized as one of two types, Raster or Vector.
A raster dataset is a digital surface where each grid-cell (pixel) has a different value. In a DEM each cell has a height value, in an aerial image each cell shows a different color. Raster datasets are used for back-drop mapping purposes, or specialist modelling functions such as drainage simulation.
To compare maps and measure distances between regions or specific features such as powerlines and roads, precise line-work is required known as vector mapping. Vector maps are composed of discrete features that can be visualized as points, lines or polygons. Each feature represents a record in an accompanying database that lists attribute information such as its unique ID, class name and size. DEPHOS Group team are experts in digitization of vector map datasets for GIS usage and have developed a range of GIS and web-based 3D information systems to share information to the public.