Open Source Software

Open-source software (OSS) is computer software with its source code made available and licensed with an open-source license in which the copyright holder provides the rights to study, change and distribute the software for free to anyone and for any purpose. This page contain links to some of the most well known remote sensing and GIS OSS as well as OSS for image processing.


GRASS GIS, commonly referred to as GRASS (Geographic Resources Analysis Support System), is a free Geographic Information System (GIS) software used for geospatial data management and analysis, image processing, graphics/maps production, spatial modeling, and visualization. GRASS GIS is currently used in academic and commercial settings around the world, as well as by many governmental agencies and environmental consulting companies. GRASS GIS is an official project of the Open Source Geospatial Foundation (OSGeo).

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    ILWIS (Integrated Land and Water Information System) is a GIS / Remote sensing software for both vector and raster processing. ILWIS features include digitizing, editing, analysis and display of data as well as production of quality maps. ILWIS was initially developed and distributed by ITC Enschede (International Institute for Geo-Information Science and Earth Observation) in the Netherlands for use by its researchers and students, but since 1 July 2007 it has been distributed under the terms of the GNU General Public License and is thus free software. Having been used by many students, teachers and researchers for more than two decades, ILWIS is one of the most user-friendly integrated vector and raster software programmes currently available. ILWIS has some very powerful raster analysis modules, a high-precision and flexible vector and point digitizing module, a variety of very practical tools, as well as a great variety of user guides and training modules all available for downloading.


    SAGA is the abbreviation for System for Automated Geoscientific Analyses. It is a is a Geographic Information System (GIS) software which has been designed for an easy and effective implementation of spatial algorithms. SAGA offers a comprehensive, growing set of geoscientific methods.


    SPRING is a state-of-the-art GIS and remote sensing image processing system with an object-oriented data model which provides for the integration of raster and vector data representations in a single environment. SPRING is a product of Brazil's National Institute for Space Research (INPE/DPI (Image Processing Division ) with assistance from:


    Quantum GIS (QGIS) is a user friendly Open Source Geographic Information System (GIS) licensed under the GNU General Public License. QGIS is an official project of the Open Source Geospatial Foundation (OSGeo). It runs on Linux, Unix, Mac OSX, Windows and Android and supports numerous vector, raster, and database formats and functionalities.


    UNESCO's Bilko is a complete system for teaching remote sensing image analysis skills. Current lessons teach the application of remote sensing to oceanography and coastal management, but Bilko routines may be applied to the analysis of any image in an appropriate format, and include a wide range of standard image processing functions.


    Open source object-based image analysis (OBIA) software for automatic image interpretation.

    The InterIMAGE Project is an International Scientific Cooperation Project led by the Pontifical Catholic University of Rio de Janeiro (PUC-Rio) and the Brazilian National Institute for Space Research (INPE). The InterIMAGE system is a knowledge based framework for Automatic Image Interpretation. InterIMAGE is an extension of an earlier project called GeoAIDA developed by the Institut fur Informationsverarbeitung - Leibniz Universitat Hannover. The interpretation strategy implemented by the system is based on a knowledge model defined by the user, structured as a semantic network. The nodes of the network represent concepts, classes of image objects expected to be found in a scene. Specialized image processing operators (external from the system's core) can be attached to the system, which controls their execution. The instances of the concepts found by the operators are then judged by the system, based on rules defined by the user.


    A Freeware Multispectral Image Data Analysis System.

    MultiSpec (Purdue Research Foundation) is a processing system for interactively analyzing Earth observational multispectral image data such as that produced by the Landsat series of Earth satellites and hyperspectral image data from current and future airborne and spaceborne systems such as AVIRIS. The primary objective of MultiSpec is as an aid to export the results of our research into devising good methods for analyzing such hyperspectral image data. It has also found significant use in other applications such as multiband medical imagery and in K-12 and university level educational activities. There are currently in excess of several thousand known, registered users.


    The goal of the OpenDragon Project is to provide high-quality, commercial-grade, free remote sensing image processing software to schools and universities. However, everyone is welcome to download and use this software.

    Orfeo Toolbox

    Orfeao Toolbox: developed by CNES of France, for object-based image analysis (OBIA). Easier to use in Linux.

    ORFEO Toolbox (OTB) is distributed as an open source library of image processing algorithms. As the motto of OTB goes, Orfeo Toolbox is not a black box, OTB encourages full access to the details of all the algorithms. OTB is based on the medical image processing library ITK and offers particular functionalities for remote sensing image processing in general and for high spatial resolution images in particular. Targeted algorithms for high resolution optical images (SPOT, Quickbird, Worldview, Landsat, Ikonos), hyperspectral sensors (Hyperion) or SAR (TerraSarX, ERS, Palsar) are available.


    RAT (Radar Tools) is a powerful open-source software tool for processing SAR (Synthetic Aperture Radar) remote sensing data. Our motivation to start the development of RAT is that modern remote sensing software like Erdas Image or ENVI include only some basic SAR functionality. Advanced algorithms in SAR polarimetry (PolSAR), interferometry (InSAR) and polarimetric interferometry (PolInSAR) have to be implemented by oneself. So we descided to start the development of RAT. RAT should bring modern SAR algorithms to a wider user-base by simplifying in particular the data handling and processing of complex SAR data.