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INTRODUCTION OF OPEN SOURCE SOFTWARE FOR GIS EDUCATION Course
project of A Nordnatur Intensive Course OpenSource GIS, GPS and Crowd
Sourcing in University of Copenhagen, Skovskolen
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A Nordnatur Intensive Course OpenSource GIS, GPS and Crowd Sourcing in University of
Copenhagen, Skovskolen
INTRODUCTION OF OPEN SOURCE SOFTWARE FOR
GIS EDUCATION
Course Project
Name: Kauri Kiiman School: Estonian University of Life Sciences Degree program: geodesy (master) E-mail: [email protected]
March 2013
2
Preface
This project compiles material prepared in the framework of the course „A Nordnatur
Intensive Course OpenSource GIS, GPS and Crowd Sourcing” from February 2013 to
April 2013.
The content is based on research in GIS and the open source software.
The goal of this paper is introduce GIS and assist GIS users towards understanding the
potential role of open source software to educate new GIS users.
This paper will provide a basic introduction of some of the available free and open
source GIS software for both – GIS teachers and students.
“Everything is related to everything else, but near things are more related than distant
things.” Waldo Tobler
3
Table of Content
1. Introduction and overview ................................................................................................................. 5
1.1. What is GIS and why? ........................................................................................................................ 5
1.1.1. Benefits of GIS? ....................................................................................................................... 6
1.1.2. What can you do with GIS? ................................................................................................ 7
1.1.3. The Geographic Approach ....................................................................................................... 8
1.2. Open Source free software ........................................................................................................... 10
1.2.1. What is free software? ........................................................................................................... 10
1.2.2. What is open source software? ........................................................................................... 10
1.2.3. When should we use open source software? ................................................................ 11
2. GIS Software ........................................................................................................................................... 13
2.1 Introduction of GIS software ........................................................................................................ 13
2.2.1. GIS Software Concepts ........................................................................................................... 13
2.2.2. GIS Software Categories ........................................................................................................ 14
2.2. List of geographic information systems software ............................................................... 15
2.2.1. Notable commercial or proprietary GIS software ....................................................... 15
2.2.2. Open source software ............................................................................................................ 17
3. Popular open source software examples for GIS ..................................................................... 20
3.1. Basic desktop GIS ............................................................................................................................. 20
3.1.1. KOSMO ......................................................................................................................................... 21
3.1.2 gvSIG .............................................................................................................................................. 22
3.1.3. uDig ............................................................................................................................................... 23
3.1.4. Quantum GIS (QGIS) ............................................................................................................... 24
3.2. Remote Sensing Software ............................................................................................................. 26
3.2.1. ImageJ ........................................................................................................................................... 26
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3.2.2. OSSIM ............................................................................................................................................ 27
3.2.3. ImageLinker ............................................................................................................................... 28
3.2.4. OpenEV ........................................................................................................................................ 29
3.2.5. ILWIS Open ................................................................................................................................. 30
3.2.5. Opticks ......................................................................................................................................... 31
3.3. 3D Visualization Tools ................................................................................................................... 32
3.3.1. ParaView ..................................................................................................................................... 32
3.3.2 NASA World Wind .................................................................................................................... 33
3.3.3. ossimPlanet ................................................................................................................................ 34
3.4. Other Open Source GIS software................................................................................................ 35
3.4.1. Server-side IMS ......................................................................................................................... 35
3.4.2. Client-side mapping browser tools ................................................................................... 36
3.4.3. Spatial Analysis Programming Tools and Library ....................................................... 36
3.4.4. Spatial databases ...................................................................................................................... 37
Conclusion ....................................................................................................................................................... 38
References ....................................................................................................................................................... 39
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1. Introduction and overview
GIS is acronym for geographic information system. An integrated collection of computer
software and data used to view and manage information about geographic places,
analyze spatial relationships, and model spatial processes. A GIS provides a framework
for gathering and organizing spatial data and related information so that it can be
displayed and analyzed. [1]
1.1. What is GIS and why?
A geographic information system (GIS) integrates hardware, software, and data for
capturing, managing, analyzing, and displaying all forms of geographically referenced
information.
Many of the issues in our world have a critical spatial component
Land management
Emergency Response
Hazard Mitigation
Property lines, easements, right of ways
Data on land values, taxation, assessment
Business site selection, advertising
Proximity of ‘our’ land to other facilities (pollution, hunting, municipal, federal,
state)
…
“I don’t know what’s over that hill” is a common problem. What is adjacent to the land we
are using? [2]
GIS allows us to view, understand, question, interpret, and visualize data in many ways
that reveal relationships, patterns, and trends in the form of maps, globes, reports, and
charts. A GIS can be thought of as a system—it digitally creates and "manipulates"
spatial areas that may be jurisdictional, purpose, or application-oriented.
A GIS helps you answer questions and solve problems by looking at your data in a way
that is quickly understood and easily shared. GIS technology can be integrated into any
enterprise information system framework. [3][4]
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GIS is unique:
GIS handles spatial information
GIS makes connections between activities based on spatial proximity
Creates relationships between otherwise unrelatable data [2]
1.1.1. Benefits of GIS?
GIS benefits organizations of all sizes and in almost every industry. There is a growing
awareness of the economic and strategic value of GIS. The benefits of GIS can be divided
into five basic categories:
Cost Savings and Increased Efficiency
GIS is widely used to optimize maintenance schedules and daily fleet movements.
Typical implementations can result in a savings of 10 to 30 percent in operational
expenses through reduction in fuel use and staff time, improved customer service, and
more efficient scheduling.
Better Decision Making
GIS is the go-to technology for making better decisions about location. Common
examples include real estate site selection, route/corridor selection, evacuation
planning, conservation, natural resource extraction and so on. Making correct decisions
about location is critical to the success of an organization.
Improved Communication
GIS-based maps and visualizations greatly assist in understanding situations and in
storytelling. They are a type of language that improves communication between
different teams, departments, disciplines, professional fields, organizations, and the
public.
Better Recordkeeping
Many organizations have a primary responsibility of maintaining authoritative records
about the status and change of geography. GIS provides a strong framework for
managing these types of records with full transaction support and reporting tools.
Managing Geographically
GIS is becoming essential to understanding what is happening—and what will happen—
in geographic space. Once we understand, we can prescribe action. This new approach to
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management—managing geographically—is transforming the way that organizations
operate. [3]
1.1.2. What can you do with GIS?
People can do a lot of things if they can and they have skills to use GIS. Here is a little list
what you can to with GIS:
Map Where Things Are
Mapping where things are lets you find places that have the features you're looking for
and to see patterns.
Map Quantities
People map quantities to find places that meet their criteria and take action. A children's
clothing company might want to find ZIP Codes with many young families with relatively
high income. Public health officials might want to map the numbers of physicians per
1,000 people in each census tract to identify which areas are adequately served, and
which are not and so on.
Map Densities
A density map lets you measure the number of features using a uniform areal unit so you
can clearly see the distribution. This is especially useful when mapping areas, such as
census tracts or counties, which vary greatly in size. On maps showing the number of
people per census tract, the larger tracts might have more people than smaller ones. But
some smaller tracts might have more people per square mile—a higher density.
Find What's Inside
Use GIS to monitor what's happening and to take specific action by mapping what's
inside a specific area. For example, a district attorney would monitor drug-related
arrests to find out if an arrest is within 1,000 feet of a school—if so, stiffer penalties
apply.
Find What's Nearby
GIS can help you find out what's occurring within a set distance of a feature by mapping
what's nearby.
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Map Change
Map the change in an area to anticipate future conditions, decide on a course of action,
or to evaluate the results of an action or policy. By mapping where and how things move
over a period of time, you can gain insight into how they behave. For example, a
meteorologist might study the paths of hurricanes to predict where and when they
might occur in the future. [2]
1.1.3. The Geographic Approach
Geography is the science that studies the lands, the features, the inhabitants, and the
phenomena of the Earth. Geomatics is a branch of geography that has emerged since the
quantitative revolution in geography in the mid-1950s. Geomatics involves the use of
traditional spatial techniques used in cartography and topography and their application
to computers. Geomatics has become a widespread field with many other disciplines,
using techniques such as GIS and remote sensing. Coupled with GIS, geography is
helping us to better understand the earth and apply geographic knowledge to a host of
human activities. [5]
The outcome is the emergence of The Geographic Approach—a new way of thinking and
problem solving that integrates geographic information into how we understand and
manage our planet. This approach allows us to create geographic knowledge by
measuring the earth, organizing this data, and analyzing and modeling various processes
and their relationships. The Geographic Approach also allows us to apply this knowledge
to the way we design, plan, and change our world. Next steps are important for the The
Geographic Approach [3] [5]:
Step 1: Ask
Frame the Question
Approaching a problem geographically involves framing the question from a location-
based perspective. What is the problem you are trying to solve or analyze, and where is
it located? Being as specific as possible about the question you're trying to answer will
help you with the later stages of The Geographic Approach, when you're faced with
deciding how to structure the analysis, which analytic methods to use, and how to
present the results to the target audience.
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Step 2: Acquire
Find Data
After clearly defining the problem, it is necessary to determine the data needed to
complete your analysis and ascertain where that data can be found or generated. The
type of data and the geographic scope of your project will help direct your methods of
collecting data and conducting the analysis. If the method of analysis requires detailed
and/or high-level information, it may be necessary to create or calculate the new data.
Creating new data may simply mean calculating new values in the data table or
obtaining new map layers or attributes but may also require geoprocessing.
Step 3: Examine
Examine the Data
You will not know for certain whether the data you have acquired is appropriate for
your study until you thoroughly examine it. This includes visual inspection, as well as
investigating how the data is organized (its schema), how well the data corresponds to
other datasets and the rules of the physical world (its topology), and the story of where
the data came from (its metadata).
Step 4: Analyze
Analyze the Data
The data is processed and analyzed based on the method of examination or analysis you
choose, which is dependent on the results you hope to achieve. Do not underestimate
the power of "eyeballing" the data. Looking at the results can help you decide whether
the information is valid or useful, or whether you should rerun the analysis using
different parameters or even a different method. GIS modeling tools make it relatively
easy to make these changes and create new output.
Step 5: Act
Share Your Results
The results and presentation of the analysis are important parts of The Geographic
Approach. The results can be shared through reports, maps, tables, and charts and
delivered in printed form or digitally over a network or on the Web. You need to decide
on the best means for presenting your analysis. You can compare the results from
different analyses and see which method presents the information most accurately. And
you can tailor the results for different audiences. For example, one audience might
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require a conventional report that summarizes the analyses and conveys
recommendations or comparable alternatives. Another audience may need an
interactive format that allows them to ask what-if questions or pursue additional
analysis.
1.2. Open Source free software
1.2.1. What is free software?
“Free software” means software that respects users' freedom and community.
Roughly, the users have the freedom to run, copy, distribute, study, change and improve
the software. With these freedoms, the users (both individually and collectively) control
the program and what it does for them.
When users don't control the program, the program controls the users. The developer
controls the program, and through it controls the users. This non free or “proprietary”
program is therefore an instrument of unjust power. Thus, “free software” is a matter of
liberty, not price. To understand the concept, you should think of “free” as in “free
speech,” not as in “free beer”.
A program is free software if the program's users have the four essential freedoms:
The freedom to run the program, for any purpose.
The freedom to study how the program works, and change it so it does your
computing as you wish. Access to the source code is a precondition for this.
The freedom to redistribute copies so you can help your neighbor.
The freedom to distribute copies of your modified versions to others. By doing
this you can give the whole community a chance to benefit from your changes.
Access to the source code is a precondition for this. [6]
1.2.2. What is open source software?
People has started using the term “open source” to mean something close (but not
identical) to “free software”. Open source software is a type of "free" software to be
accessed, used or modified by their user groups and developers. There are many similar
terms to describe this kind of software, such as “free software”, “libre software”, “open
software”, etc. One key feature to distinguish open source software from other types
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(such as proprietary software and shareware) is their “free software licenses”, which
explicitly define the legal rights to users with freedoms to run, study, change,
redistribute, and access the source codes of the licensed software. All open source
software is required to be “licensed”. The procedure of implementing “free software
licenses” is necessary to protect their users’ legal rights and to ensure the freedoms of
the software.
Prefer the term “free software” because, once you have heard that it refers to freedom
rather than price, it calls to mind freedom. The word “open” never refers to freedom. [6]
1.2.3. When should we use open source software?
Both proprietary GIS software and open source GIS software are equally important for
GIS education. In practice, open source stands for criteria a little weaker than those of
free software. As far as we know, all existing free software would qualify as open source.
Nearly all open source software is free software, but there are exceptions. First, some
open source licenses are too restrictive, so they do not qualify as free licenses.
Fortunately, few programs use those licenses.
Second, and more important, many products containing computers (including many
Android devices) come with executable programs that correspond to free software
source code, but the devices do not allow the user to install modified versions of those
executables; only one special company has the power to modify them. We call these
devices “tyrants”, and the practice is called “tivoization” after the product where we first
saw it. These executables are not free software even though their source code is free
software. The criteria for open source do not recognize this issue; they are concerned
solely with the licensing of the source code.
Many GIS teachers select proprietary GIS software for GIS education because students
can learn the mainstream software skills and have advantages in the job markets. On the
other hand, some GIS teachers prefer to use open source software because it is free of
cost and allows for the freedom to modify and distribute GIS applications. This paper
will not argue which direction is better for GIS education, but rather suggest when GIS
teachers should or could use open source software. In the following situations, it may be
a good opportunity to consider open source software in your classes:
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Teachers would like to explore the possibility of teaching GIS in a very short
period, but do not have immediate financial support from schools or software
vendors to purchase GIS software.
Students would like to install and try GIS software on their home computers.
School computers are using non-Windows operating systems, such as MacOSX or
Linux.
Teachers would like to highlight a certain aspect of GIS functions, such as
database management, web mapping, remote sensing, or spatial analysis, and
they may realize that commercial GIS packages do not provide these individual
functions, or the cost of adding these additional functions are too expensive.
Teachers would like to demonstrate some unique GIS functions to students
tomorrow. (Most commercial GIS software will take more than one week to
finalize the licensing with vendors. You can download and use open source
software immediately.) [6][7]
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2. GIS Software
2.1 Introduction of GIS software
Software that is used to create, manage, analyze and visualize geographic data, i.e. data
with a reference to a place on earth, is usually denoted by the term ‘GIS software’.
Typical applications for GIS software include the evaluation of places for the location of
new stores, the management of power and gas lines, the creation of maps, the analysis of
past crimes for crime prevention, route calculations for transport tasks, the
management of forests, parks and infrastructure, such as roads and water ways, as well
as applications in risk analysis of natural hazards, and emergency planning and
response. For this multitude of applications different types of GIS functions are required
and different categories of GIS software exist, which provide a particular set of functions
needed to fulfill certain data management tasks. We will first explain important GIS
software concepts, then list the typical tasks accomplished with GIS software, describe
different GIS software categories, and finally provide information on software producers
and projects. [8]
2.2.1. GIS Software Concepts
To represent a geographic object in a GIS, e.g. a building or a tree or a forest, a data
representation has to be established first. GIS usually provide two different possibilities
to represent (a geographic phenomenon): the raster representation and the vector
representation. In the raster representation a regular mesh of cells is used, where every
cell records the value of the attribute that describe the phenomenon - like the RGB
values in a digital image. Raster’s are typically used to represent variables that are
continuous over space, such as terrain elevations or land cover. In the vector model,
which is commonly used to store objects that are spatially discrete, every object is
represented by a (vector) geometry (e.g.; a point, a line, or a polygon) and value fields
that describe the non-spatial object properties, the so-called ‘attributes’, in a table. For
instance, a building might be represented by rectangle geometry and have attached two
fields that describe the construction year and the owner.
In GIS software geographic objects that have the same geometric and attribute
representation are typically grouped in so-called ‘layers’ to simplify data management
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tasks. For instance, all buildings that are represented by polygons and have information
on owner and construction year are grouped in a layer ‘buildings’. In Figure 1 we show
the typical graphical user interface of a GIS software package that includes the concept
of geometries (map view) connected to values in tables (attribute view), as well as
layers that contain one class of objects (e.g. rivers). [4][8]
2.2.2. GIS Software Categories
Different types of GIS software exist with different functionality, as not every GIS user
needs to carry out all of the above tasks. For instance an assistant in the public services
department of a city may only provide information on house owners to construction
companies and does not need to edit the cadastral dataset. Figure 1 summarizes commonly
used GIS software categories.
Figure 1. Different types of GIS software
Desktop GIS usually serve all GIS tasks and are sometimes classified into three functionality
categories: GIS Viewer, GIS Editor, and GIS Analyst. Spatial Database Management Systems
(DBMS) are mainly used to store the data, but often also provide (limited) analysis and data
manipulation functionality. WebMap Servers are used to distribute maps and data over the
internet1. Similarly, WebGIS Clients are used for data display and to access analysis and
query functionality from Server GIS over the internet or intranet. Libraries and Extensions
provide additional (analysis) functionality that is not part of the basic GIS software, for
instance functions for network and terrain analysis, or functions to read specific data
formats. Finally, Mobile GIS are often used for field data collection.[8]
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Software Manufacturers and Projects
GIS software is not only provided by companies but increasingly also by free and open source
software projects. While commercial vendors usually offer products for all of software
categories, open software projects often concentrate on a single category, e.g. desktop GIS or
WebMap server. The key players in the GIS software market today are Autodesk, Bentley,
ESRI Inc., GE (Smallworld), Pitney Bowes (MapInfo), and Intergraph. GIS software
companies tend to target specific application domains. For instance, ESRI’s ArcGIS product
tends to be mainly used for business analysis, planning, and environmental applications,
while Autodesk, GE and Bentley products are rather used in utility and facility
management. Competitive GIS software that is developed by free software projects exists as
well - especially with respect to server applications (MapServer, GeoServer) and spatial
DBMS (PostGIS). Free desktop GIS projects, such as Quantum GIS and gvSIG, currently
experience growing user communities. Such free GIS software rather complements the set of
proprietary software instead of competing with it. [8]
2.2. List of geographic information systems software
2.2.1. Notable commercial or proprietary GIS software
Desktop GIS
*Almost all of the below companies offer Desktop GIS and WebMap Server products.
Some offer Spatial DBMS products as well.[9]
Companies with high market share:
MapInfo by Pitney Bowes Software – Powerful desktop GIS MapInfo Professional is
enhanced with many plug-ins including MapInfo Drivetime for route analysis, MapInfo
Engage 3D for 3D and statistical analysis, MapInfo MapMarker for Geocoding.
Autodesk – Products that interface with its flagship AutoCAD software package include
Map 3D, Topobase, and MapGuide.
Bentley Systems – Products that interface with its flagship MicroStation software
package include Bentley Map and Bentley Map View.
Erdas Imagine by ERDAS Inc – Produ www.scanpointgeomatics.com cts include Leica
Photogrammetry Suite, ERDAS ER Mapper, ERDAS ECW JPEG2000 SDK (ECW (file
format)) are used throughout the entire mapping community (GIS, Remote Sensing,
Photogrammetry, and image compression) and ERDAS APOLLO.
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Esri – Products include ArcView 3.x, ArcGIS, ArcSDE, ArcIMS, ArcWeb services
and ArcGIS Server.
IGiS by ScanPoint Geomatics Ltd. – A complete GIS.
Intergraph – Products include G/Technology, GeoMedia, GeoMedia
Professional, GeoMedia WebMap, and add-on products for industry sectors, as well
as photogrammetry.
RemoteView by Overwatch – RemoteView is one of the most widely used imagery
analysis tools within the US government to collect geospatial intelligence.
Smallworld – developed in Cambridge, England (Smallworld, Inc.) and purchased
by General Electric. Used primarily by public utilities.
SuperMap Inc. – Chinese company of GIS software. It produces Desktop, Component
and Service GIS for Asia and global markets.
Companies with minor but notable market share
Aquaveo – Developers of GMS, WMS, SMS, which are modular hydrology programs with
3D mapping features.
GeoConcept & opti-time – Business oriented GIS packages with 3D, 4D, Geomarketing,
optimization features
Cadcorp – Products include Cadcorp SIS, GeognoSIS, mSIS and developer kits.
Caliper – Products include Maptitude, TransModeler and TransCAD.
Dragon/ips – Remote sensing software with GIS capabilities.
ENVI – Utilized for image analysis, exploitation, and hyperspectral analysis.
Field-Map – GIS tool designed for computer aided field data collection, used mainly for
mapping of forest ecosystems.
Geosoft – GIS and data processing software used in natural resource exploration.
IDRISI – GIS and Image Processing product developed by Clark Labs at Clark University.
Affordable and robust, it is used for both operations and education.
Manifold System – GIS software package.
Belsis – CAD and GIS solutions available as Desktop and Web application products.
Netcad – Desktop and web based GIS products developed by Ulusal CAD ve GIS
Çözümleri A.Ş..
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RegioGraph by GfK GeoMarketing – GIS software for business planning and analyses;
company also provides compatible maps and market data.
Spatialinfo – provides GIS solutions for telecommunication networks. Products include
spatialNET, spatialWEB, spatialOFFLINE, spatialCONFLATOR, ADDRESSmanager and
MAPupdater.
Spatial DBMS
Boeing's Spatial Query Server – Spatially enables Sybase ASE.
DB2 – Allows spatial querying and storing of most spatial data types.
Informix – Allows spatial querying and storing of most spatial data types.
Microsoft SQL Server 2008 – The latest player in the market of storing and querying
spatial data. GIS products such as MapInfo and Cadcorp SIS can read and edit this data
while ESRI and others are expected to be able to read and edit this data within the next
few months.
Oracle Spatial – Product allows users to perform complex geographic operations and
store common spatial data types in a native Oracle environment. Most commercial GIS
packages can read and edit spatial data stored in this way.
PostGIS – Based on the free PostgreSQL database.
Teradata – Teradata geospatial allows storage and spatial analysis on location-based
data which is stored using native geospatial data-types within the Teradata database.
VMDS – Version managed data store from Smallworld.
Spatial Data Transformation Tools
Safe Software – Spatial ETL products including FME Desktop, FME Server and
the ArcGIS Data Interoperability Extension.
2.2.2. Open source software
*The development of open source GIS software has - in terms of software history - a long
tradition with the appearance of a first system in 1978. Numerous systems are available
which cover all sectors of geospatial data handling. [9]
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Desktop GIS
GRASS GIS – Originally developed by the U.S. Army Corps of Engineers: a complete GIS.
gvSIG – Written in Java. Runs on Linux, Unix, Mac OS X and Windows.
ILWIS (Integrated Land and Water Information System) – Integrates image, vector and
thematic data.
JUMP GIS / OpenJUMP ((Open) Java Unified Mapping Platform) – The desktop GISs
OpenJUMP, SkyJUMP, deeJUMP andKosmo all emerged from JUMP.[3]
MapWindow GIS – Free desktop application and programming component.
Quantum GIS (QGIS) – Runs on Linux, Unix, Mac OS X and Windows.
SAGA GIS (System for Automated Geoscientific Analysis) –- A hybrid GIS software. Has a
unique Application Programming Interface (API) and a fast growing set of geoscientific
methods, bundled in exchangeable Module Libraries.
uDig – API and source code (Java) available.
Besides these, there are other open source GIS tools:
Capaware – A C++ 3D GIS Framework with a multiple plugin architecture for
geographic graphical analysis and visualization.
FalconView – A mapping system created by the Georgia Tech Research Institute for the
Windows family of operating systems. A free, open source version is available.
Kalypso – Uses Java and GML3. Focuses mainly on numerical simulations in water
management.
TerraView – Handles vector and raster data stored in a relational or geo-relational
database, i.e. a frontend for TerraLib.
Whitebox GAT – Transparent GIS software.
Other geospatial tools
*Apart from Desktop GIS exists a variety of other GIS software types. For its
categorization see GIS software. A general overview of GIS software projects for each
category was done in 2012. Below is a similar listing of open source GIS projects.
Web map servers
GeoServer – Written in Java and relies on GeoTools. Allows users to share and edit
geospatial data.
MapGuide Open Source – Runs on Linux or Windows, supports Apache and IIS web
servers, and has APIs (PHP, .NET, Java, and JavaScript) for application development.
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Mapnik – C++/Python library for rendering - used by OpenStreetMap.
MapServer – Written in C. Developed by the University of Minnesota.
OpenMap – Java-based mapping toolkit from BBN Technologies.
Spatial database management systems
PostGIS – Spatial extensions for the open source PostgreSQL database, allowing
geospatial queries.
SpatiaLite – Spatial extensions for the open source SQLite database, allowing geospatial
queries.
TerraLib – Provides advanced functions for GIS analysis.
Software development frameworks and libraries (for web applications)
GeoBase (Telogis GIS software) – Geospatial mapping software available as a Software
development kit, which performs various functions including address lookup, mapping,
routing, reverse geocoding, and navigation. Suited for high transaction enterprise
environments.
Geomajas – Open source development software for web-based and cloud based GIS
applications.
MapFish – Aggregates the power of OpenLayers, ExtJS and GeoExt.
OpenLayers – Open source AJAX library for accessing geographic data layers of all
kinds, originally developed and sponsored by MetaCarta.
Software development frameworks and libraries (non-web)
GeoTools – Open source GIS toolkit written in Java, using Open Geospatial
Consortium specifications.
GDAL / OGR
Orfeo toolbox
Cataloging application for spatially referenced resources
GeoNetwork open source – A catalog application to manage spatially referenced
resources
Other tools
Chameleon – Environments for building applications with MapServer.
MapPoint – A technology ("MapPoint Web Service", previously known as MapPoint
.NET) and a specific computer program created by Microsoft that allows users to view,
edit and integrate maps. [9]
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3. Popular open source software examples for GIS
*This chapter is based on Ming-Hsiang Tsou and Jennifer Smith article: Free and open
source software for GIS education.[10][11][12][13][14]
The following chapter will introduces some useful open source software for GIS
education. To provide an easy-to-follow guidance for GIS educators, related open source
software has been categorized into five domains*:
Basic desktop GIS
Remote sensing software
3D visualization tools
Others (Web mapping servers and clients, spatial programming tools and
libraries, spatial databases)
*Details of open source software have been illustrated for the first three categories (basic
desktop GIS, remote sensing software and 3D visualization tools). Only summarized
descriptions for the rest of open source GIS software have been provided due to the project
limits.
3.1. Basic desktop GIS
Basic desktop GIS software can provide basic GIS functions, such as data input, map
display, spatial query, attribute query and spatial analysis. Most open source desktop
GIS software can be installed on multiple operating systems (Windows, MacOS, Linux
and so on). However, one common problem in open source desktop GIS software is the
lack of advanced cartographic functions and symbolization. Of course, some offer the
capability to export the mapping results as a scalable vector graphic (SVG) format to
subsequently edit it in OpenOffice Draw (another open source software) or utilize
cartographic support with InkScape.
21
3.1.1. KOSMO
Available: http://www.opengis.es/ (download file size: 108MB - available OS: Windows
and Linux)
Figure 2. Program Kosmo desktop [1.4]
KOSMO (figure 2) is one of the most popular (Java-based) open source desktop GIS,
providing a nice Graphic User Interface (GUI), GIS data editing tools, and spatial analysis
functions. KOSMO was developed based upon OpenJUMP, which is a light and simple
version of open source desktop GIS, offering very limited graphic and symbol functions.
KOSMO has improved cartographic and spatial analysis functions from OpenJUMP,
providing a friendly and comprehensive GIS package for desktop computers. One major
advantage of both OpenJUMP and KOSMO is the capability for users to edit/modify
vertices (a very detailed level of segment nodes) in vector-based layers.
22
3.1.2 gvSIG
Available http://www.gvsig.com (file size: 89MB, available OS: Windows, Linux and
MacOS X)
Figure 3. gvSIG Desktop [1.5]
gvSIG (figure 3) was developed by the European GIS community offering multiple
language user interfaces. More than ten different languages (including Spanish, French
and Chinese) can be selected to display the menus and tools. This feature is extremely
useful to teach GIS in a non-English-spoken community.
gvSIG is well known for its flexible GIS data input format. You can use various GIS data
formats (both vector and raster) and online resources (such as WMS, WCS and WFS).
gvSIG has nice vector data editing functions. Users can easily digitize lines by snapping
vertices to existing nodes and generate correct topology. With an easy-to-configure
locator map, gvSIG immediately reveals where you are in your dataset. Some GIS
professionals believe that gvSIG is becoming close to replacing ESRI ArcMap software.
23
3.1.3. uDig
Available http://udig.refractions.net/ (file size: 94 MB, available OS: Windows, Linus,
and MacOS ).
uDig (figure 4) is also a popular Java-based desktop GIS software. The name, uDig,
stands for “User-friendly Desktop Internet GIS”. Therefore, uDig offers strong capabilities
to integrate Web mapping technologies, such as WMS, WFS, remote ArcSDE, WCS,
GeoRSS and KML. The uDig website includes great tutorials and walkthrough documents
for first-time users. uDig is built upon IBM's Eclipse platform with a “clean” user
interface. uDig provides several good GIS functions, including the Styled Layer
Descriptor (SLD) support, Web Catalog Server support, and thematic mapping with
advanced symbology. uDig is also a great choice for Desktop GIS software.
Figure 4. Program uDIG desktop [1.6]
24
3.1.4. Quantum GIS (QGIS)
Available http://www.qgis.org/ (file size: 89MB, available OS: Windows, UNIX, Linux,
and MacOS).
Quantum GIS (QGIS) provides a very nice integration with Python, a scripting language
to customize or automate GIS functions. Python is probably the most popular GIS
programming language now because ESRI ArcGIS also adopts Python for their
programming functions. There are many different versions of QGIS available for
download. After the download, it may be necessary to change the installation directory
for QGIS to a root folder (such as C:\QGIS) rather than accepting the default [/programs
files] directory if you are using Windows Vista or Windows 7. You may have some
problems installing this program initially because of file written permission problems.
Changing the default installation directory to a root folder may solve this issue.
QGIS supplies a really good manual and tutorials. (Available:
http://www.qgis.org/en/documentation/manuals.html). The software provides useful
GIS tools in spatial analysis, geoprocessing, geometry, and data management tasks. Two
unique features of QGIS include the linkage (expendable) to GRASS functionalities and
the support of DWG file formats. QGIS (figure 5) supports basic ESRI shapefiles and
coverage formats, but not personal geodatabases. It also includes good Web linkages,
including WMS and WFS.
Figure 5. Quantum GIS Desktop
25
3.1.5. GRASS
Available: http://grass.osgeo.org/ (file size: 88MB, available OS: Windows, MacOS,
Linux)
GRASS (figure 6) is one of the oldest public domain GIS software in existence and has
become open source for quite some time. The full name of GRASS is “Geographic
Resource Analysis Support System”. The U.S. Army Construction Engineering Research
Laboratories originally developed GRASS in 1985. It offers comprehensive GIS analysis
functions for both vector and raster datasets. The original user interface of GRASS was in
command line only. Quantum GIS can embed all GRASS functions via a graphic user
interface (GUI) for easier public use. Multiple data input formats are available, including
MySQL, .DBF, Post GIS, and SQLite There are many federal government agencies using
GRASS for their GIS projects, including NOAA, NASA, and the US Census Bureau. A wide
range of applications and extensions of GRASS have been created for different needs of
scientific research.
Figure 6. GRASS GIS Map Display [1.7]
In general, there are many excellent open source software packages in the category of
basic Desktop GIS. GIS educators can select the appropriate software that suits their
classroom needs and/or hardware arrangements.
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3.2. Remote Sensing Software
Compared to basic Desktop GIS, there are fewer selections of open source remote
sensing software packages. While there are fewer, these programs still offer many
advanced and comprehensive tools for image processing, enhancement, and analysis.
3.2.1. ImageJ
Available: http://rsbweb.nih.gov/ij/ (file size: up to 42MB – depending on OS)
(Available OS: Windows, Linux and Mac OS X).
ImageJ (figure 7) was developed at the National Institutes of Health as an open source
software package. ImageJ allows users to open, display, edit, process, and analyze 8-bit,
16-bit and 32-bit images in the following formats: TIFF, GIF, JPEG, PNG, DICOM, BMP,
PGM and FITS. By downloading or writing additional plug-ins, you can open and process
additional image formats and numerous new functions as well (plugins:
http://rsb.info.nih.gov/ij/plugins/index.html). ImageJ includes comprehensive
processing capabilities such as geometric transformations, image enhancement (edge
detection, sharpening, smoothing, etc.) and color processing
(http://rsbweb.nih.gov/ij/features.html). The program can also stack multiple images in
one display that are correlated spatially or temporally with the same size and bit depth,
allowing the user to scroll through them interactively.
Figure 7. Screenshot of ImageJ examples [1.8]
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3.2.2. OSSIM
Available www.ossim.org (minimum size (depending upon OS): 382MB, OSSIM and
OSSIM Planet are available for Windows, Linux, and Mac).
OSSIM is a software program that includes numerous advanced image processing tools
to support GIS, remote sensing, and photogrammetry. Under constant development,
OSSIM aims to improve its processing abilities while funded under a number of US
government agencies. The full name of OSSIM is Open Source Software Image Map, which
has been nicknamed “awesome” by their first government customer. OSSIM provides
useful tutorials in PDF (available: http://download.osgeo.org/ossim/tutorials/ ) and a
user guide (http://download.osgeo.org/ossim/docs/pdfs/ossim_users_guide.pdf). Some
functions in the program include: supporting numerous map projections and datum’s,
sensor modeling, native file access, ortho rectification, elevation support, vector and
shapelib support, histogram matching, and tonal balancing .
Figure 8. Screenshots of programm OSSIM tools [1.9]
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3.2.3. ImageLinker
Through their Visual Chain Editor (VCE), users can create, connect and change “image
chains” (multiple images). Users can also utilize and/or create plugins within
ImageLinker to add new functionality to the program.
Figure 9. Screenshot of ImageLinker displaying two images. [1.10]
Nice tutorial is available:
http://download.osgeo.org/ossim/docs/pdfs/ImageLinker_Tutorial.pdf
29
3.2.4. OpenEV
Available http://openev.sourceforge.net (file size: up to 26.7MB, available OS: Windows,
Linux, Irix, and Solaris)
Figure 10. Screenshot of an image display in OpenEV. [1.11]
OpenEV is a software program that displays and analyzes vector and raster data and
offers a library for developers to construct new applications
(http://openev.sourceforge.net/). First created by Atlantis Scientific (now Vexcel), the
program was later obtained by Microsoft and developed into the satellite imagery
viewer available now. OpenEV can display large datasets, from georeferenced images to
elevation data in 2D and 3D. Some of the features include image enhancement, image
comparison, overlay and on-screen digitizing for image analysis. [11]
30
3.2.5. ILWIS Open
Available http://52north.org (file size: up to 17.8MB zipped, Available OS: Windows)
ILWIS Open, short for Integrated Land and Water Information System, was developed by
ITC (the International Institute for Geo-Information Science and Earth Observation) in the
Netherlands. ILWIS is a combination of both a GIS and remote sensing package that can
display, process and analyze image (raster), vector and thematic data. Documentation
can be downloaded at http://52north.org/downloads/ilwis/documentation, detailing a
very comprehensive explanation of the features and capabilities of ILWIS (begin with
preface). Features available for vector data include digitizing, display, interpolation,
calculations and more. For raster data, the functions include creation of digital elevation
models, slope, aspect, distance calculation, and more. With satellite images, some of the
features users can execute include statistics, filters, mosaic, georeferencing,
classifications and histograms. Importantly, when you are ready to create the final
output of your data, ILWIS offers annotation functions and printable outputs.
Figure 11. Screenshot from ILWIS [1.12]
31
3.2.5. Opticks
Available http://opticks.org/confluence/display/opticks/Welcome+To+Opticks
(file size: up to 49MB zipped files, available OS: Windows, Solaris, and limited support
for Linux).
Opticks is a remote sensing software package that supports many types of imagery and
remote sensing data such as motion imagery (videos), Synthetic Aperture Radar (SAR),
multi-spectral, and hyper-spectral data. [12] First developed by Ball Aerospace &
Technologies Corporation for the US Air Force, Opticks was originally created for
hyperspectral analysis and designed to be less complicated to use than the ENVI
software [13]. In 2007, Opticks was released to the public as an open source software
package. Supported data include: NITF, GeoTIFF, JPEG2000, ENVI, Raw formatted files,
HDF5, Hyperion, DTED, Shapefiles (.shp and from ArcSDE), CGM, AOI/ROIs, ENVI,
Spectral, ASPAM/PAR, Annotations, and Color Maps/Tables . There are extensive
Opticks functions accessible such as displaying false color images, histogram production,
added annotations, creation of animations, all available bands, linking frames,
georeferencing, performing filters, automation, and creating your own algorithms. There
are also available extensions for additional functionality as well as the ability to develop
your own extensions.
Figure 12. Screenshot of Opticks, a classification [1.13]
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3.3. 3D Visualization Tools
In response to the growing popularity of 3D GIS data and geovisualization, several open
source programs are being developed. Through the addition of a new dimension, users
can both analyze and visualize more spatial object relationships and spatial patterns
than previously available. This additional display space offers room for creativity in
visualization. Users are able to not only map elevation of desired objects, but display and
represent attribute data with height as well. Some popular open source 3D visualization
software packages are introduced below.
3.3.1. ParaView
Available http://www.paraview.org/ (file size: up to 119MB, available OS: Windows,
MacOSX, Linux).
ParaView was first publicly released in 2002. The program can analyze very large
datasets and has the ability to display data in 3D. Some of the different file formats
supported include VTK, polygonal files, EnSight, Plot3D, and many more because users
can provide their own readers. There are many features offered in ParaView such as
filters, extracting and displaying contours, clipping/cutting features, grid computations,
statistics and display. Extensions can add functionality to the software program through
download or by scripting your own in the Python language.
Figure 12. Screenshot of ParaView interface [1.14]
33
3.3.2 NASA World Wind
Available: http://worldwind.arc.nasa.gov/download.html (file size: 16MB, available OS:
Windows, but the new World Wind Java SDK will operate for Windows, MacOS, & Fedora
Core 6, file size: 24.69MB).
Originally released in 2004, NASA World Wind is a virtual globe that displays satellite
images from NASA and USGS, aerial photos, topographic maps and GIS data on a 3D
virtual earth [14]. Aside from Earth, World Wind has provided other planets (Moon,
Mars, Venus and Jupiter) for display and exploration as well. The website includes an
easy to follow key chart instructing the user how to navigate the virtual globe with their
keyboard and mouse. Users can import shapefiles, kml/kmz files, and other geospatial
data to display on the virtual globe. With an embedded digital elevation model (DEM)
and bathymetry, World Wind visualizes objects in 3D, viewable when you zoom into
different features that have height and depth, including trenches and ridges. With the
high-resolution visualization, it is a great tool for analysis and display because of the
great detail it provides. Upon zooming in, political boundaries, place names, and latitude
and longitude gridlines can be seen if desired for enhanced visual effects. Like many
other programs, World Wind also allows for new plug-ins to add new functionality such
as displaying new paths, polygons, and names. USGS has also developed a set of
geoprocessing tools that work inside WorldWind.
Figure 13. Screenshots of data visualized in the NASA World Wind Interface [1.15]
34
3.3.3. ossimPlanet
Available: http://www.ossim.org/OSSIM/ossimPlanet.html (file size depending upon
OS: minimum 192MB, available OS: Linux, Mac, Windows).
ossimPlanet is an accurate 3D virtual globe built upon the OSSIM software for
visualization and remote collaboration. It can handle many commercial and government
datasets including OSSIM Geo-Spatial Formats, GDAL Geo-Spatial Formats, kml/kmz files
and Predator UAV mpg clips. The virtual globe renders elevation and tree topography on
the fly, enriching the visual display for users of ossimPlanet. To help users begin, there is
a good instruction manual available for each operating system on the web site (windows
manual, http://download.osgeo.org/ossim/installers/windows/ossimPlanetUsers.pdf).
It is important to note that users must have a three-button mouse in order to navigate
the virtual globe.
Figure 14. Screenshot of ossimPlanet [1.13]
35
3.4. Other Open Source GIS software
The following open source software packages can provide advanced GIS functions, such
as web mapping services, advanced spatial analysis and spatial databases. If GIS teachers
need to create specialized GIS courses in their labs or programs, these software may be a
good choice.
Web mapping servers and clients
The whole GIS industry is moving into the direction of Internet GIS and Web mapping.
Thousands of Web GIS applications have been created and used in many websites [15]
However, most commercial Internet Map Servers (IMS) are very expensive and not
affordable for GIS educators. Open source IMS can provide a good alternative for GIS
educators to create and introduce web mapping services to their students. There are
two types of web mapping software: server-side IMS and client-side map browser tools.
3.4.1. Server-side IMS
MapServer
Available: http://mapserver.org/
MapServer is probably the oldest and the most popular open source IMS. The platform
was originally developed at the University of Minnesota in 1994 with NASA funding.
MapServer is a CGI program (common gateway interface). CGI is an early Internet GIS
technology. Therefore, the user interface and mapping functions are limited in
comparison to other IMS that use advanced AJAX or FLEX technologies. Despite this,
performance of MapServer is still useful for most basic web mapping services.
GeoServer
Available: http://geoserver.org/display/GEOS/Welcome
GeoServer is also a popular Java-based open source IMS, created by The Open Planning
Project in 2001. GeoServer can provide advanced Web mapping protocols such as OGC's
WMS and WFS. It can also provide transactional editing. The generic web interface is
very interactive and easy to use.
MapGuide Open Source
Available: http://mapguide.osgeo.org/
MapGuide has a very unique situation in terms of open source software license.
AutoDesk created MapGuide originally as proprietary software. In 2005, AutoDesk
36
released MapGuide as open source under LGPL and made the source codes available for
open source developers. The installation procedure of MapGuide server is more
complicated than other IMS, which may be challenging for beginners. MapGuide Open
Source can provide a very powerful map engine and advanced client-side map browser
tools and technologies.
3.4.2. Client-side mapping browser tools
OpenLayers
Available: http://openlayers.org/
OpenLayers is a client-based JavaScript library that can be customized in a HTML
document for displaying map data. OpenLayers does not create its own mapping images
from GIS databases, but instead displays map layers derived from other (external) IMS
engines. Thus, it is a client-side application rather than an IMS. Openlayers is a very
powerful client-side mapping tool offering great performance, but requiring a certain
level of programming skill in order to use or customize its interface. Additionally,
because it is based on JavaScript and it does not work well in Internet Explorer web
browsers.
Mapfish
Available: http://mapfish.org/
Mapfish is also a JavaScript-based client-side mapping tool created by utilizing the Pylon
Python web framework. Similar to OpenLayers, Mapfish is compliant with various IMS
output protocols, such as WMS, WFS, KML, GML, etc.
3.4.3. Spatial Analysis Programming Tools and Library
STARS (Space-Time Analysis of Regional Systems)
Available: http://regionalanalysislab.org/index.php/Main/STARS
STATS is an easy-to-use open source software designed for the analysis for areal data
(such as counties or zip-code areas) measured over time. Program is created with the
Python programming language.
PySAL
Available http://geodacenter.asu.edu/projects/pysal
37
PYSAL is an open source library of tools for spatial analysis developed by the GeoDa
Center at Arizona State University.
3.4.4. Spatial databases
PostGIS
Available http://postgis.refractions.net/
PostGIS is the most popular open source GIS database engine built upon the PostgreSQL
object-relational database. Many developers consider that PostGIS is a strong challenger
to several commercial GIS databases, such as Oracle Spatial and Microsoft SQL Server
Spatial.
GearScape
Available: http://www.fergonco.es/gearscape/
GearScape is another good open source tool to develop GIS databases. If you are looking
for software to learn/teach spatial SQL, GearScape is a good instructional tool because it
provides a spatial SQL implementation and the results of the queries are shown directly
on the active map.
Summarized
Most of these open source tools and packages can be accessed from:
The Open Source Geospatial Foundation http://www.osgeo.org/
OpenGeo website http://opengeo.org
38
Conclusion
Although many private GIS software companies such as ESRI, Microsoft and Google
played an important role for GIS development in the past, the Open Source Software
Society has become a stronger player in the GIS industry.
The process to adopt open source GIS may not so quick in comparison to commercial
solutions, but it is affordable and importantly, offers customization of the software for
your needs.
With the introduction of this project, I was hoped that GIS educators and learners can
realize the potential of open source GIS software for their courses.
For example: QGIS – it has come a long way in the last few years, it has database support,
it has now good support OGC standards like VMS and WFS, and its support almost any
format. NASA World Wind can offer an excellent virtual earth demo by linking to
multiple NASA satellite images and the WMS layers directly.
Paul Ramsey had said (paper: “The State of Open Source GIS”):
"The change to open source requires a different mindset. Rather than one programme or
one suite of programs delivering everything you need, you go over to different programs
that all communicate with each other and use the same (standard) protocols and data
formats."
I hope that this little project proves to be useful for GIS educators: to try open source GIS
software.
In the market (internet) there are lot of different kinds of programs – you just need to
choose, what best fit for you. But remember: data is what matters, not software,
programs are just tools. Find a tool that does what you want with your data and
workflows, don`t force your workflows and data to bend to the software needs.
As GIS technology develops every year, some of the information for open source
software, what is mentioned in this project, may be out-of-date or incorrect. If you have
comments, some new ideas, find new open source GIS software’s or you see any errors
in this project – please note me and send: [email protected]
I will incorporate your suggestions into the next project, where I will correct that and
hopefully there are some new materials too.
39
References
[1] ESRI GIS Dictionary. (2013). Retrieved March 18, 2013, from
http://support.esri.com/en/knowledgebase/GISDictionary/term/GIS
[2] Introduction to Geographic Information Systems. (2011) Retrieved March 20, 2013,
from
http://www.lib.virginia.edu/scholarslab/resources/class/mlbs/introToGIS.pdf
[3] ESRI GIS overview. Retrieved 20, 2013, from
http://www.esri.com/what-is-gis/overview
[4] Wikipedia, Geographic information systems, Retrieved March 15, 2013, from
http://en.wikipedia.org/wiki/Geographic_information_system
[5] Wikipedia, Geography, Retrieved March 15, 2013, from
http://en.wikipedia.org/wiki/Geography
[6] GNU Operating System, The free software, Retrieved March 15, 2013, from
http://www.gnu.org/philosophy/free-sw.html
[7]=[9] Tsou, M. and Smith, J. (2011) Free and Open Source software for GIS education,
National Geospatial Technology Center of Excellence, Retrived March 6, 2013, from
http://geoinfo.sdsu.edu/hightech/WhitePaper/tsou_free-GIS-for-educators-
whitepaper.pdf
[8] Steiniger, S. and Bocher, E. (2009) An overview on current free and open source
desktop GIS developments, International Journal of Geographical Information Science,
23:10, 1345 - 1370.
[9] Wikipedia, List of geographic information systems software, Retrieved March 7,
2013, from
http://en.wikipedia.org/wiki/List_of_geographic_information_systems_software
[11] Ramsey, P. (2007). The State of Open Source GIS. Refractions Research, Victoria, BC,
Canada.
[12] Wikipedia, GRASS GIS, Retrieved March 24, 2013, from
http://en.wikipedia.org/wiki/GRASS_GIS
[13] Wikipedia, OpenEV, Retrieved March 24, 2013, from
http://en.wikipedia.org/wiki/OpenEV
[14] Wikipedia, Optics, Retrieved March 24, 2013, from
40
http://en.wikipedia.org/wiki/Opticks
[15] History of Optics, Retrieved March 27, 2013, from
http://opticks.org/confluence/display/opticks/History+of+Opticks
[16] NASA World Wind, Retrieved March 27, 2013, from
http://en.wikipedia.org/wiki/NASA_World_Wind
Pictures and figures (from Google):
Title page pictures:
[1.1]http://www.hopkinsvilleky.us/agencies/planning-commission/planning-page
photos/gis.jpg
[1.2] http://www.mdpi.com/1999-5903/4/2/451
[1.3] http://publicworks.nl/wp-content/uploads/2010/11/socrata_open_data.png
Figures:
[1.4] http://live.osgeo.org/_images/kosmo3.jpg
[1.5]http://outreach.gvsig.org/sites/gvsigoutreach.drupalgardens.com/files/CU_PER_ca
tastro_municipal_2.png
[1.6] http://udig-news.blogspot.com/2012/09/udig-132-released.html
[1.7] http://en.wikipedia.org/wiki/File:Wxgui-atm.png
[1.8] http://img.teck.in/imagej.jpg
[1.9] http://www.ossim.org/OSSIM/OSSIM.html
[1.10] http://live.osgeo.org/_images/ossim-imagelinker3.jpg
[1.11] http://earth.unibuc.ro/images/588.png
[1.12] http://fatwaramdani.files.wordpress.com/2012/07/pca_using_ilwis7.jpg
[1.13]http://img.brothersoft.com/screenshots/softimage/o/opticks-208211-
1233481273.jpeg
[1.14] http://technology.qatar.tamu.edu/rc/paraview.JPG
[1.15] http://www.bullsworld.net/wp-content/uploads/2009/03/eoli.jpg
[1.16] http://wiki.osgeo.org/images/a/a2/KoreaOverview.jpg
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