Geographic Information Systems (GIS)
QGIS or uDig Open Source Geographic Information Systems (GIS) allow to enter, process, analyze and display geographic information. The use of a GIS is essential when a geographic component is present in the data. Indeed, the notion of geography can not be taken into account adequately only as attribute data. Tools and specific skills are needed to fully exploit the potential of this dimension.
Entering geographic information must be done via the use of a base map as repository. On this basis, the user can graphically enter points, lines or polygons. In some cases, data entry rules will have to be specified/defined and tools to assist with data entries will be available, for example: snapping (magnetic objects), topological rules or projection coordinates tools (azimuth, distance) or linear referencing (determining a coordinate based on distance along a line from a known starting point).
In addition to the graphical geometries input, the attributes information taking into account the data model is implemented in a GIS.
The processing of geographic information includes various operations which allow to prepare data based on the final use.
- From an attribute information (X, Y coordinates / address / ZIP, etc..) and possibly a lookup table, georeferencing allows to obtain a geographical area that can be represented on a map.
- Format conversion between different data sources, while preserving the attribute and geographical components as well as conversion between raster and vector formats.
- Reprojection allows to switch from a reference system (geographic or Cartesian) to another. For example, data specific to a country can be rescaled in a global system in order to integrate them into a map of the entire map local system.
- The pooling of different data sets, such as for example the creation of a set of data including supra-regional data including the entities of several different regions with all required modifications for the homogeneity of results.
- The creation of new geographical entities or topological geometry validation based on spatial operators.
A wide variety of analysis functions is available and allows to extract relevant information from the data:
- Queries and geographic selections
- Geographic measures
- Determining geographic relationships between different objects (from the same data source or from multiple sources of data)
- Analysis of graphs and networks
- Interpolation, merging geometries, etc.
Ideally, geographic information is apprehended in the form of a map. Thus, a GIS has the features to prepare relevant maps. Meeting the rules of graphic semiology facilitates reading and interpreting maps. Different elements must be depicted on a map, such as the legend, the scale, the indication of the North, and the reference of data sources with a title and a date. Similarly, a rich variety of types of maps can be produced, such as, for instance, a 2D view to a 3D view and the creation of cuts or views profiles. Different themes are possible: for examples, the proportional symbol display, the camembert view, the histograms such as the choropleths maps, etc. Depending on the amount of data to present and the display scale, processes of generalization of data are necessary.
Different standards in geospatial solutions guarantee the interoperability and the compatibility of data sources. A GIS must comply with the standards of the Open Geospatial Consortium (OGC), including the following norms:
- Web Map Service (WMS): displaying a web image from a remote server
- Web Feature Service (WFS): access to raw data (geometry and attributes) of a layer of geographic data from a remote server
- Web Coverage Service (WCS): download a geo-referenced raster
- Web Map Tiling Service (WMTS ): displaying a layer from a remote server
QGIS is a user-friendly Geographic Information System (GIS), providing a rich variety of geographical features and integrating multiple data formats (vector, raster, database). A plugin system allows to extend the GIS with new features or to build solutions to meet the challenges in the fields of electricity, water, real estate, environment, security, etc.
QGIS is an official project of the Geospatial Open Source foundation (OSGeo) and is distributed under GNU public general license. It is compatible with Linux, Unix, Mac OS X, Windows and Android. The core of QGIS is programed in C++ and its plugins in Python.
Camptocamp uses and actively participates to the development of QGIS. All news on QGIS is available here:
uDig is a desktop GIS framework for Eclipse, published under Open Source license (EPL or BSD). uDig can be used as an independent application, be extended with RCP plugins or can be used as a plugin in an existing RCP application. The goal of uDig is to provide a complete solution for creating GIS in JAVA.
Camptocamp uses and actively participates to the development of uDIG.
Camptocamp offers solid skills in software development and in geomatics. We help you achieve successfully your GIS projects and specific vertical solutions. The size of our team and its various skills allow us to be your contact for all matters relating to any GIS aspects. Camptocamp can:
- help define the architecture of your GIS solutions and advise your development teams;
- implement new features in Open Source GIS features that will then be donated to the community source code to ensure sustainability;
- develop layers specific to your business, all based on Open Source GIS for advanced use in a particular context (management of the water network, power grid management, determination of environmental impacts, issues related to security, etc.;
- train you to use Open Source GIS and to develop of plugins.