Tag Archives: QGIS

So What is Open Source Exactly?

This term ‘Open Source’ pops up in discussions about Community Health Maps and the blog and I realize many may not really know what it means. That’s OK, I’m going to explain it here. From both licensing and software development perspectives, there are two broad categories of computer software: proprietary and open source. The figure below shows some examples of both types.

FOSS_vsProprietary

Examples of Open Source & Proprietary Software

Proprietary Software 

Proprietary software is created and sold by a corporation. They create software and sell it to make a profit. When purchasing it you may also be paying for the privilege to get help and support using the software. Or you may have to pay extra for that privilege. Two examples of proprietary software are Microsoft Office and Esri’s ArcGIS. There is also a license that accompanies a proprietary software package. When you purchase software, you are actually just buying a license that gives you the rights to operate the software. You never actually own the software itself. That software license will restrict use in some way:

  1. the number of computers you are allowed to install the software onto,
  2. the time period that the software will operate, and
  3. the number of features you are licensed to use.

Open Source Software

Open source software (OSS), on the other hand, is created by a community of software developers (programmers). It is created to solve a common problem and is made available freely for everyone’s use. Open Office, Android and QGIS are examples. Open source software also comes with a license. That license tends to grant rights to users. For example:

  1. The freedom to run the software for any purpose.
  2. The freedom to study how the software works.
  3. The freedom to redistribute copies so you can help your neighbor.
  4. The freedom to improve the program.

Access to the source code may not be important to most, but the freedom to use the software as you see fit very well may be.

open-source

Why Give it Away for Free?

To many it is counter-intuitive for something of value to be given away for free.  However, open source software development isn’t entirely altruistic. Most of these programmers work for companies providing services with the software. Those involved in an open source project simply feel that this is a better way to create software. There are several reasons for this:

  1. there are a lot of “eyes” on the code and bugs can be spotted and fixed quickly,
  2. having access to the source code let’s you understand how the software is working, it’s not a ‘black box,’
  3. you are not locked into a particular vendors system, licensing scheme or software release schedule,
  4. you have the freedom to create any missing functionality that you need
  5. you benefit from the contributions of others and vice versa.

Making Money with OSS

Obviously you can provide services using OSS. However, there are other ways to make money with open source. Companies like Facebook, IBM, Sun, and Google are all heavily involved in open source. Let’s take the example of Google. They may be the world’s largest open source company. One of the keys to their business are vast server farms, which include several million servers. Google never would have been able to get their company off the ground if it weren’t for the Linux operating system. The cost of putting a proprietary operating system like Windows on all those servers would have been prohibitive. Now their open source Android operating system is the most popular on the market with a 66.5% market share. In another example, even Esri’s ArcGIS includes some open source software components ‘under the hood.’ This is because some open source software licenses allow that software to be bundled with proprietary software and sold for profit.

Any given open source software is considered a ‘project’ and they aren’t all user friendly and useful. You still have to determine if the software will meet your needs. An important aspect is getting help and support. Things to look for include a good online manual, ‘how-to’ books, and an active listserv.

QGIS

Let’s take QGIS as an example. It has fantastic support. It has a great online manual, training material, case studies, sample maps, commercial support, email listservs, plus a number of ‘how-to’ books written by people who use QGIS. The QGIS project does not have a corporation behind it. It has about 30 independent but dedicated core developers. They work in a democratic fashion, voting on new features to be implemented. As an end user you can provide input with feature requests! With QGIS, if there is a feature you need that doesn’t exist, you can hire (sponsor) a programmer to create it. It then may become part of the core program or it may be written as a standalone plugin. That feature then becomes part of the software and everyone benefits. As a user of the software, you can easily contact someone involved in developing the software and ask questions and request features. With proprietary software you never have such direct access to the development team. You can also donate to the QGIS project. Your donation will pay for developers to fix bugs and implement new features. Beyond programming there are many ways people can contribute to a project like QGIS. You can report bugs when you encounter them, write and translate documentation, contribute a case study, and write books.

Summary

Open source is both a development methodology and a software license. In the end it is really impossible to say that a proprietary software like ArcGIS is better than the open source equivalent like QGIS or vice versa. You must decide if either works for you, and freedom and monetary cost may be part of that decision.

End Note:

There are a lot of acronyms in GIS and specifically open source GIS. Here are some you may encounter:

FOSS = Free and Open Source. Historically there were two similar software movements, Free Software and Open Source software. They are so similar that they now are lumped together, and people simply use this acronym when talking about them.

FOSS4G – Free and Open Source for Geospatial. This is free and open source software specifically for mapping. OsGeo (below) holds annual open source GIS conferences called FOSS4G. The next is coming up later this month in Bonn, Germany.

OsGeoOpen Source Geospatial Foundation – this is a non-profit organization whose mission is to foster global adoption of open geospatial technology by being an inclusive software foundation devoted to an open philosophy and participatory community driven development. To be considered an OsGeo project a software must meet certain requirements. QGIS is a project under the OsGeo umbrella.

How Does Esri Software Fit into the CHM Workflow?

Community Health Maps (CHM) necessarily focuses on low cost and open source tools. This is because our goal is to find mapping tools that can be used by any community group, no matter the budget or resources. However, that doesn’t preclude people from using Esri software or other proprietary mapping tools too.

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One benefit of using Fulcrum for data collection, and QGIS for analysis and cartography, is that they both support a wide range of common GIS formats. This means that the data you’ve created via these two platforms can be easily brought into Esri’s ArcGIS software. Similarly if you have data you have created with Esri tools they can be brought into QGIS or Carto. This feature is known as ‘interoperability’ and QGIS is highly interoperable. For example, QGIS can work with shapefiles, Esri personal and file geodatabases, KML and over 100 other formats!

From the outset we knew there were many scenarios for mapping software being used in public health and community organizations.  For instance, there are larger organizations who are already using tools such as Esri’s ArcMap, ArcGIS Pro or ArcGIS Online. With this scenario there are still several reasons the CHM mapping tools could be useful.

  • It might be that the organization doesn’t have enough Esri licenses for everyone in the office who’s interested in doing mapping work. In this case Fulcrum, QGIS or Carto could be used to fill the need.
  • An organization may find that their Esri license doesn’t give them access to certain tools they need. They could use comparable tools in QGIS to fill the need, without having to pay extra license fees just for one or two extra tools.
  • There may be smaller affiliated satellite groups that don’t share the same access to the software. In this case, these groups could use CHM suggested tools. Because of good interoperability they would then be able to provide data back to the central hub, where they could be incorporated seamlessly with the rest of the organizations data.
  • There may be certain tasks that are easier and faster to do in one piece of software and others that are easier in another. For example, I use both ArcGIS and QGIS daily to do different things. Many beginners also find QGIS to be more intuitive. GIS is simply a tool and by incorporating QGIS you are giving yourself a bigger toolbox.

If you are in an organization using another software package don’t worry. The tools we are promoting as part of this project can be integrated quite seamlessly with your current tools. It doesn’t have to be Coke or Pepsi, or Ford or Chevy. You can have both!

Mapping Curb Ramp Accessibility around a Silver Spring, MD Assisted Living Facility

Submitted by Jenny Rewolinski, University of Maryland, B.S. Community Health 2016

I just completed a spring internship with the National Library of Medicine (NLM). My goal was to demonstrate what a typical user of the Community Health Maps (CHM) blog might experience, while using the low cost resources it reviews to develop a mapping project with a public health focus. I read through the case studies on the CHM blog and used its labs to develop my project plan and to guide my related decisions.

Because of my experience with elderly relatives and my background in public health, I centered my project on how the senior population of a nearby Assisted Living Facility might safely navigate local sidewalks. According to the 2014 American Community Survey, 23% of people over 65 have some sort ambulatory disability. With this in mind, I decided to map local curb ramps –sloped transitions between sidewalks and streets which function as accessibility enhancements to help those with mobility issues to cross streets safely.

JennyDataCollection

Figure 1. Curb Ramp Data Collection using the iForm app

I used CHM Lab 1: Field Data Collection to learn how to design my own data collection form using iForm. My Curb Ramp form captured curb ramp location, conditions, and other observations such as seniors using the curb ramps, steep or damaged curb ramps, and a lack of sidewalks in the area. As discussed in a prior blog post, How Accurate is the GPS on my Smart Phone?, phone geolocation is usually accurate up to 8 meters. This was not precise enough for my curb ramp data, so I corrected for this on my form.  Over the course of 8 hours spanning 2 days, and with 2 other interns I collected 103 existing curb ramps and locations where curb ramps might aid accessibility.

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Figure 2. iForm Curb Ramp Data Collection Form

Next, I brought my iForm curb ramp data from my phone into the QGIS software by using instructions from CHM Lab 2: Bringing Field Data into QGIS.  I also used CHM Labs 3: Combining Field Data with Other Organizational Data and CHM Lab 4: Basic Spatial Analysis  to add data layers and to perform spatial analysis to finalize my map.

Map

Figure 3. Curb Ramp Accessibility of Senior Population of Silver Spring Assisted Living Center Map

This is my project map! I completed construction of my map using CHM Lab 5: Cartography with QGIS. In addition to my curb ramp data points, I added data layers for sidewalks, roads, places of interest (such as grocery stores, restaurants, bus stops,  theaters), and my Assisted Living Facility. My goal was to raise awareness of how accessibility can impact seniors’ sense of autonomy and empowerment, and their ability to exercise and to lead a healthier lifestyle. This map also provides recommendations for where more curb ramps should be placed based on observations during data collection. I plan to discuss this map and curb ramp recommendations with the city of Silver Spring and to create “safest route” guides for popular local destinations.

SafestRoute

Figure 4. A Safest Route Guide example showing safe and dangerous routes based on location of curb ramps and sidewalks

GIS has a huge potential to help us analyze health issues. When I began my project at NLM, I thought I would simply be mapping the location of curb ramps near a local Assisted Living Facility; however I discovered the significant need for more curb ramps as well as sidewalks around my project area.

I believe the conclusions I was able to reach by using the low cost CHM resources CHM are accurate and workable. I came to NLM with little to no GIS knowledge yet I learned from the CHM GIS labs, collected curb ramp data points and created a map that may bring awareness to a public health issue. In doing so I believe my experience is typical of many CHM users.

If I can do it, you can too!

Discover QGIS – A new QGIS workbook!

Two years ago, myself and several colleagues authored the GeoAcademy which is the first ever GIS curriculum based on a national standard – the U.S. Department of Labor’s Geospatial Competency Model (GTCM). The GTCM consists of the knowledge, skills and abilities needed to be a working GIS professional.  Our team was honored with the 2015 GeoForAll Educator of the Year award for this effort. The GeoAcademy consists of 5 complete college courses.

  • Introduction to Geospatial Technology Using QGIS
  • Spatial Analysis Using QGIS
  • Data Acquisition and Management Using QGIS
  • Cartography Using QGIS and InkScape
  • Remote Sensing Using QGIS and GRASS

This winter I converted the curriculum to fit into a convenient workbook format with Locate Press. The workbook is called Discover QGIS.

As you may be aware, QGIS is evolving rapidly. A new version is released every 4 months!  Due to this rapid development pace each spring a long-term release (LTR) is created. The LTR version is supported for a calendar year and is better for production environments. Originally written for QGIS 2.4, the GeoAcademy material in this workbook has been updated for use with QGIS 2.14 LTR. It therefore represents the most up-to-date version of the GeoAcademy curriculum. In addition to working with QGIS, it also includes exercises doing analysis tasks with the powerful GRASS GIS software, both alone and via the GRASS QGIS plugin. The cartography section includes exercises with InkScape. Here you’ll learn how to begin a map in QGIS and use InkScape to finish a publication quality map.

At the moment the digital version of the workbook is available as a Preview Edition for only $24.99. Purchasing this preview entitles you to the full version when it is released. There are just a few formatting issues to resolve.

This book will be a great resource for Community Health Mappers wanting to build their skills. The 470 page workbook comes with exercise data, challenge exercises and solution files!

Discover QGIS

Discover QGIS

APTR: Teaching Prevention – Albuquerque, NM

Community Health Mappers had a strong presence at the recent APTR Teaching Prevention conference held in Albuquerque, New Mexico last week.

APTR Teaching Prevention Conference Logo

APTR Teaching Prevention Conference Logo

The theme of the conference was Preparing Students to Address Emerging Issues, and four students presented work incorporating the CHM mapping protocol. Medical University of South Carolina (MUSC) College of Nursing students Caitlin Baker and Carleigh Fox presented a  poster on their project “A Diabetes Epidemic in Rural South Carolina.” They used mobile devices to conduct a windshield survey of a rural South Carolina community to better understand the diabetes epidemic.

Caitlin Baker and Carleigh Fox Presenting at the APTR Poster Session

Caitlin Baker and Carleigh Fox (MUSC) Presenting at the APTR Poster Session

Amy Tseng, a student at the University of Washington’s School of Public Health, presented a poster outlining her project, “Evaluating of the Wellness for Asian Pacific Americans Using GIS.” This is her capstone project in the Community Oriented Public Health Practice program . One question she is attempting to answer is whether there is a relationship between having a sense of community and the density of Asian Pacific Americans  in a given neighborhood. She is utilizing QGIS and Fulcrum to help answer this question.

Amy Tseng (UW) Presenting at the APTR Poster Session

Amy Tseng (UW) Presenting at the APTR Poster Session

Christina Yantsides, also in the School of Public Health at the University of Washington, presented her capstone project, “Bicycle Injuries and Fatalities: A GIS Mapping Project” in both a the Sunday afternoon lightning session, and the Sunday evening poster session. She is using QGIS to help identify clusters of bicycle accidents in Seattle and gain a better understanding of the causal factors.

Christina Yantsides (UW) Presenting at the APTR Poster Session

Christina Yantsides (UW) Presenting at the APTR Poster Session

The final morning of the conference myself, John Scott, Dr.  Deborah Williamson (MUSC) and Dana Burshell (MUSC) presented the “National Library of Medicine (NLM) Community Health Mapping Project.” Often conference attendees are tired by the final morning. However, we were excited to present to a standing room only crowd of about 75 attendees! Collectively we introduced the project and the National Library of Medicine, and went on to show how successfully the project has been implemented from Hawai’i to South Carolina. I heard several audible gasps from the audience as we presented examples. This caused me reflect on the fact that mapping and GIS is simply what I do all day long, however, to many it is still a new and exciting tool. We finished with a quick live demo of downloading data from Fulcrum and uploading it into CartoDB to show how quick and easy it is.

John Scott, Deborah Williamson, Kurt Menke and Dana Burshell Before Presenting at APTR

John Scott, Deborah Williamson, Kurt Menke and Dana Burshell Before Presenting at APTR

Collectively it was a very successful demonstration of how Community Health Mapping can be used by community organizations, educators and students. APTR was a very interesting conference and a great fit for Community Health Mapping. Several conference organizers suggested we teach a Community Health Mapping workshop at next years conference! Looks like we will be back!

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Amy Tseng, Sarah Reynolds, Kurt Menke, John Scott, Deborah Williamson, Dana Burshell and Christina Yantsides at APTR

A New Version of QGIS v2.14 Has Been Released!

Currently a new version of QGIS is released every four months!  To help users deal with this rapid development pace, the version put out each spring is designated as a long-term release (LTR). This means it will be supported for one calendar year. After that, new stable versions continue to be posted quarterly and any bug fixes associated with those quarterly versions are applied to the LTR. The LTR is recommended for production environments. It has a slower release cycle, and receives regular bug fixes throughout the year. Monday February 29th QGIS 2.14, the next LTR was released. It is nicknamed ‘Essen’ after the town in Germany where a recent developer meeting was held.

essen

QGIS Essen

Essen has a lot of new features. You can visit the Visual Changelog to read about all the new features in detail. You can also see who developed and sponsored each new feature. Community Health Mappers might be especially interested in these new features:

  • the new 2.5 D renderer which allows you to extrude features into space.
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Example of 2.5 D Rendering by Nicholas Duggan @ XYHT.com

  • improved labeling
  • better control over map elements in the Print Composer
  • an improved Processing Toolbox
  • the new widget you get by right clicking on a layer in the Layers Panel and choosing Style. It allows you to change the color for a symbol without having to open a single dialog box!
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Style Widget

If you are using QGIS you should visit the download page and install the latest version! Note that the Mac installer takes a little longer to assemble and may not be available for several more days.

Happy GIS’ing!

Wildly Successful Community Health Mapping Workshops at MUSC!

Community Health Maps (CHM) conducted it’s largest and most successful workshops ever at the end of September at the Medical University of South Carolina (MUSC). The training at MUSC was divided into three workshops and a presentation. The attendees were a mix of professors, students and researchers, most of whom had little to no experience with GIS. Despite this fact, nearly everyone was able to collect data and make a map. This is a testament to the easy to use nature of the CHM workflow.

It began Monday morning with the first workshop. This was an Intermediate Session for those Community Health Mappers who had been working on projects since the April CHM workshop. We spent two hours covering more advanced topics and answering project specific questions.

Kurt Menke explaining advanced QGIS features.

Kurt Menke explaining advanced QGIS features.

Following that, Kurt Menke presented a CHM project overview at a brown bag lunch session to 30 attendees. Matt Jones closed this session with a 10 minute talk detailing how he used The Community Health Maps workflow this summer to map access to care on Johns Island.

The second workshop was Monday afternoon. It was a two hour session covering field data collection with iForm, and mapping that data online with CartoDB. There were 55 attendees at this session, the vast majority of whom had no GIS experience. In just two hours all 55 attendees were able to collect field data and make a map in CartoDB!

iForm and CartoDB Workshop Attendees

iForm and CartoDB Workshop Attendees

The final workshop on Tuesday was a 5 hour session covering the use of QGIS. The workshop consisted of a custom Charleston based QGIS exercise. Each of the 35 participants worked with a set of Charleston GIS data while learning the basic layout of QGIS. They learned how to add data, style it, and compose a map. The workshop ended with a discussion of each participants goals and project specific questions.

QGIS Workshop Attendees

QGIS Workshop Attendees

In total almost 80 people attended one or more sections of the training! Thanks go out to Dr. Deborah Williamson for hosting the workshops, Dana Burshell for organizing the entire event and assisting during the workshops, and to Sarah Reynolds who was invaluable in providing Mac and QGIS support!