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137
votes
56answers
11k views

What free programs should every GIS user have installed?

Note: This question is specifically about installed, desktop software. There is another question specifically about free cloud-based software and services. I'm not necessarily referring to ESRI ...
45
votes
20answers
12k views

What are some Free and Open Source GIS Desktop packages

Can someone please give me a list of free and open source GIS desktop packages?
30
votes
5answers
9k views

Comparison of the different open source GIS servers

I currently know the following open source GIS servers: Geoserver: java based, vector and bitmap support, also supports. Is now on par with mapserver (performance-wise). mapserver: c/c++, used to be ...
19
votes
9answers
2k views

Discontinuous or Interrupted map projections?

Do any of the current open source GIS softwares support discontinous projection systems? E.g. sinusoidal, dymaxion, butterfly, etc? If not, are there any affordable commercial ones that do (affordable ...
40
votes
8answers
12k views

Creating drive time polygons using open source tools

Is anyone using open source tools and/or data to generate drive time polygons that radiate out from a given location? For example, I have used ESRI products like Network Analyst and Business Analyst ...
10
votes
3answers
3k views

Land Cover Feature Extraction from Satellite Imagery

I'm interested in a low-cost or open source solution for creating land cover GIS layers that utilize both spectral and textural extraction algorithms. I have used PCI Geomatica, ENVI, and Feature ...
7
votes
7answers
4k views

Extract raster values at points

How can I extract values from a raster by points. I prefer not in Arcgis. I prefer in Qgis or Mapwindow or other open source gis.
31
votes
9answers
11k views

Open source methods for kriging?

I have a point dataset which I'd like to Krige, ideally using an open-source software package. If possible, I'd also like to choose the semi-variogram model during the process to improve the ...
12
votes
4answers
5k views

free GIS software that can orthorectify?

Would someone care to recommend a free and/or open source GIS application that can orthorectify map images?
7
votes
3answers
1k views

How to interpret GRASS v.kernel results?

GRASS manual reads: v.kernel - Generates a raster density map from vector points data using a moving 2D isotropic Gaussian kernel ... Ok, but how do I interpret the results? I understand that ...
39
votes
4answers
2k views

What are the FOSS equivalents to these ArcGIS products?

I'm a long-term user of ESRI software, and I now have a need to use free and open source software. I've been reading about Open Layers, PostgreSQL, PostGIS, GeoServer and MapServer but I can't find ...
16
votes
7answers
13k views

Is there an open source Geocoding tool which can be used commercially?

Is there any Geocoding tool which is open source and can be used in commercial application? We tried Google geocoding API's but cannot continue with it because of some licensing limitation. Now ...
21
votes
5answers
4k views

Is there any model builder in QGIS or other open source GIS?

Like the ModelBuilder of ArcGIS for Desktop to run simultaneous geoprocessing tools, is there any model builder available in QGIS or any other open source GIS software?
14
votes
2answers
4k views

How can I switch baselayers as a user zooms in to the map in OpenLayers

I have a map which overlays Open Street Map data on imagery for Pennsylvania. As a baselayer to the roads (and eventually other layers) I have two baselayers - Blue Marble NG and USGS EROS 1ft ...
10
votes
4answers
722 views

Suggestions for simple mapping platform for alumni web site

I'm working on a proof of concept alumni site with a WordPress backend. I want to have a very simple map that shows where alumni are living. I'm thinking something like the Bing API or a simple open ...
8
votes
2answers
2k views

How to calculate average slope in a grid?

This is actually a two part question: Which methods are there to calculate average slope by unit (say km²) for a given area? Are there any special requirements on the data - like additional ...
27
votes
8answers
13k views

Open Source Tool capable of reading Esri File Geodatabase (.gdb)?

I have an ESRI File Geodatabase (.gdb) file that I would like to convert to shapefile (or any other non-proprietary format). Are there any Open Source tools to do so?
7
votes
5answers
10k views

Comparison of Open Source Desktop GIS Packages

I'm curious as to what comparisons are out there between different Open Source Desktop GIS software packages. I'm aware that there has been a QGIS and gvSIG comparison on this site but I am looking ...
11
votes
9answers
11k views

Is there a comprehensive list of latitude and longitude values for cities around the world?

I'm developing an application that calculates the distance between cities using their respective Longitude and Latitude values. But the problem is where to get a comprehensive list of latitude and ...
1
vote
1answer
729 views

Delineate polygonal catchment areas from a raster using open-source GIS

I'm 90% sure this basic question has been asked before but looking through the other posts I simply do not see a useful answer. I need to calculate polygonal(vector) catchment areas from a raster ...
37
votes
6answers
9k views

Free GIS workshops, tutorials, and applied learning material

Note 1: Please enter answers separately or feel free to edit this post directly Note 2: Please report on any broken links so they can be removed This thread lists free as in $0 workshops in GIS and ...
23
votes
9answers
2k views

How to easily shift all features in a vector dataset?

Let's say that I put together a Shapefile and all the features have their vertices shifted by a constant amount. What's the easiest way of shifting all the features (hence the (x,y) position of their ...
20
votes
7answers
2k views

Alternatives to Network Analyst

I'm not sure how reasonable this question even is, but it leaves me no less curious after a bit of searching. If I am looking to build a network based on road features and attributes, is Network ...
13
votes
3answers
6k views

Post Processing GPS Data with open source software

I am using Magellan Professional Mapper CX working on ArcPad 7.1 platform. It has sub-meter accuracy after post processing. Without post processing the data collected in the field is off by 10 to 15 ...
12
votes
4answers
1k views

Python module to delete SHP features (without Desktop GIS installed)

I have a piece of software (not Arc) that runs nightly on a non-production machine which updates shapefile features from an external database. Periodically I would like to delete all of the features ...
14
votes
5answers
4k views

A SQL console in QGIS

I know QGIS comes with its field calculator, which is not bad. It also comes with ftools which permits several operations on geometry and attributes. But we often need more control and I haven't seen ...
4
votes
1answer
1k views

Open Source Alternatives to ERDAS IMAGINE ATCOR?

I have been using ERDAS IMAGINE's ATCOR extension for ATmospheric CORrection of ASTER imagery. What opensource options exist for atmospheric correction of ASTER Level 1B products? I'm primarily ...
10
votes
5answers
1k views

Seeking Open Source ISO Metadata Editor?

I am looking for a free open source ISO metadata editor for the development of an enterprise database. It will mostly be used for documenting shapefiles and GeoTIFFs. Hoping that it will be an ...
9
votes
10answers
3k views

Need a Benchmark GPS Trajectory data-set? Anyone?

I'm looking for a benchmark GPS data set, available for research purposes for free. I've found GeoLife GPS Trajectories dataset from Microsoft Research but I find it a little incomplete. What I need ...
6
votes
4answers
2k views

Is it possible to create 3D dxf with OGR?

Does anyone know if it's possible to create a 3D dxf with OGR. I would like to assign our contour lines a z value and export them to dxf for some cad work. PS I know FME can do this, however I would ...
6
votes
3answers
708 views

Can we use GeoExt Freely?

I want to know, can we use GeoExt freely? is there any need to purchase some license for using GeoExt ? Actually i am already working with free Open source tools (OpenLayers+GeoServer) for my webMap ...
1
vote
1answer
831 views

psycopg2 error with QGIS 1.5

So I just installed QGIS 1.5 using the windows installer not the osgeo4w one and now any plugins that need access to PostgreSQL databases don't seem to work, they all throw a: "Couldn't import Python ...
9
votes
0answers
3k views

Open source alternative to FME from Safe Software for Spatial ETL? [duplicate]

Just wondering if there is any open source solution which comes close to safe FME? I would like to integrate it into my workflow, but it´s just another few thousand which my employer has to give out ...
35
votes
1answer
4k views

How to smooth the polygons in a contour map

Here is a contour map for which all the polygons of levels are available. Let ask how to smooth the polygons keeping all vertices preserved in their exact locations? Indeed the contour is made on ...
16
votes
5answers
2k views

Rendering overlapping lines

I am making a map containing information about public transportation: busses, trams, etc. The map will have a layer containing for example the tram lines. Each line has its own colour, and is ...
14
votes
6answers
1k views

Creating simple image from vector data

Can anyone suggest a quick (and preferably open source) way to create an image from a shapefile. For example, I have a shapefile containing parcel boundaries, I want to create a png file depicting ...
24
votes
7answers
2k views

Work flow for georeferencing imagery using open source tools?

Does anyone have a recommendation for a work flow for georeferencing high resolution aerial photography using open source tools? Comparison of user friendliness and robustness between Quantum GIS ...
19
votes
4answers
1k views

How to generate schemas of GIS hardware / software / workflows?

Quite often I find myself in a situation where I need to explain hardware or software GIS infrastructure to people with no or limited knowledge of GIS. Or give an overview of geoprocessing tasks ...
19
votes
5answers
3k views

What is Change Detection and how I can perform such analysis with open source tools?

From wikipedia page: Change detection for GIS (geographical information systems) is a process that measures how the attributes of a particular area have changed between two or more time periods. ...
8
votes
3answers
1k views

Do any open-source .Net libraries (commercially usable) exist for reading/writing LiDAR data?

I have a few LiDAR point data (.las files) with me. I would like to read the X,Y and Z from it using .Net. I found liblas, which is in C++ and I am not sure if it can be used commercially after ...
7
votes
2answers
3k views

Creating noise maps using ArcGIS for Desktop or Open Source Desktop GIS?

In a previous role I helped create Noise Maps for Northern England. The predicted noise levels was done using the IMMI package (which I can recommend) and the cartographic output was done in ArcMap. ...
7
votes
4answers
1k views

How to clip LAS data using shapefile polygons and open source software?

I am trying to clip or filter lidar files (las, xyz) using a shapefile that contains multiple polygons. Is there open source software that can do this spatial operation? My las files are enormous, ...
14
votes
4answers
443 views

Is there a FOSS solution for legend parsing in a web mapping environment?

Our web mapping requirements are fairly standard - some basic querying and the ability to print out the resulting map (or save the image). Typically we've used ESRI products in the past (right now ...
10
votes
14answers
6k views

Which GIS support DXF and/or DWG?

Which GIS support DXF and/or DWG (preferably read&write)? Update: Are there any open source GIS supporting these or similar CAD files? Support of CAD files generally seems to be problematic. ...
9
votes
3answers
3k views

Get all vertices of a polygon using OGR and Python

I'm having a little trouble with the Python OGR API. What I am trying to do is get all the coordinates of each vertex of the outer ring of a polygon. This is what I have so far: import osgeo.ogr ...
6
votes
1answer
994 views

Open source tool for point/node conflation/matching?

The Question Are there any open source tools for conflating (matching) two layers of point (node) data? Motivation I'm particularly interested in using such a tool to sync data with OpenStreetMap, ...
5
votes
3answers
2k views

3D visualisation with open source GIS software [closed]

I'm searching for QGIS (or other open source GIS software) tools that can analyse XYZ data. Also I'm interested to hear about if anyone have migrated to non commercial software regarding geological ...
4
votes
3answers
2k views

How to calculate orientation of line segments using open source GIS?

I'd like to calculate the orientation of line segments relative to north direction using open source tools. Which tools or functions would you recommend?
9
votes
2answers
409 views

How do I generate a large number of maps?

I have to make a large number (hundreds) of distribution maps of species. I have a shapefile that contain the distributions for each species, and for each one, I would like to get a map as an image ...
9
votes
1answer
2k views

Reverse Geocoding Libraries

I'm new to GIS and mapping services. Can anyone tell me what my options are for reverse-geocoding libraries, other than nominatim? I'm most likely going to be working with OpenStreetMap data. So ...