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Day 573: OpenSource Mapping Tools On The Web

Or what Maitri has been putzing with when not working, reading or blogging. FYI, this post is not an exercise in geekery; it involves free visual mapping tools that anyone at any level of computer expertise can get around, learning a new skill and helping your community and you understand your particular space and its statistics. The visual representation of data helps us make sense of spreadsheets, quickly allocate the proper resources to problem areas and discuss future direction. The only caveat: Keep it OpenSource – what each of us builds becomes community intellectual property.

GoogleEarth is acquiring more acceptance in industry and academic concerns as the mapping tool of choice. This includes the positioning of data-rich 2D maps as well as vertical slices of the earth in a 3D reference frame (e.g. data from remote sensing exercises, such as seismic or electromagnetic). In the 2D realm alone, Google Earth can act in conjunction with Google Maps to take material from existing databases and map them as points or layers. The bottom line is that, along with the API, there are an endless number of tools and results that can be created. For right now, my concerns are crime and population mapping in New Orleans and seismic data in the Gulf of Mexico.

Are you still wondering why this is important to you? Ok. As only the latest application, AnyGeo reports that Farallon Geographics has developed a 2D/3D map tool for the Boston Redevelopment Authority. Extrapolate such a tool to our rebuilding city.

Farallon implemented a web application to integrate the City’s permitting system with an enterprise database using GIS. Fast and simple access to 2D & 3D maps, City GIS data, and project specific redevelopment information, was developed using web services that dynamically overlay GIS results onto Virtual Earth. The result is a clever mashup that will no doubt make you think about Microsoft Virtual Earth … Check out images of the application [here].

gCensus ScreenshotAnother clever use of this interface that I’ve been studying is Irfan Haq’s gCensus, a project that “makes geographic data freely and easily accessible to the public, without the need for expensive GIS software packages.” Irfan has only the 2000 US Census database loaded and the interface is ready for just three US states, but this is a big accomplishment by one person and there is more coming. gCensus is the kind of project that requires many hands and computers. Which brings us to New Orleans.

ExtremeTech has a book out called Hacking Google Maps and Google Earth (better description at Amazon.com), which “gives you a detailed explanation on building your own community site through Google Maps.” This book (among others) shows you how to use concepts of GIS to tweak Google Earth and create your own local mashup. Think of the possibilities for our area: plotting maps of the current population, overlaying them with maps of business, crime, rebuilding permits or whatever you choose as long as you have a current database. Why is this important? Such a set of free mapping tools gives the citizen a visual layout of the data pertaining to city or neighborhood. This in turn helps generate intelligent conclusions for further discussion and action.

NOLA Citizen Crime Watch Screenshot 1One such shining example in our area is Citizen Crime Watch. Read on, learn something new and help out! Emphases mine.

The goal: to create an open source crime mapping, reporting, and alert system for the community, so that citizens might have a greater awareness about the safety of their neighborhood.

The main problem: In concert with the New Orleans community, a team of volunteers is now working on more fully developing this site into an even more feature-rich and meaningful tool for understanding crime trends, but they can’t do it alone. For this concept to work, citizens will need to assert their ownership of timely, accurate data from the New Orleans Police Department. There are other data sources, such as “scraping” the data from NOLA.com incident report pages. The problem with these other sources is that they are incomplete and irregularly published — if published at all.

I’ve learned that simply mentioning the problem of city mapping in a blog post brings all kinds of resources out of the woodwork. For instance, Ann Arbor’s Ed Vielmetti responded to my last post with

As for mapping things, there’s a new way to put blog entries on a Google Maps map. I think it’s as easy as installing GeoPress from this site and then feeding the resulting feed into Google Maps a la what this example looks like, which is an example of what a Flickr feed looks like on a map.

As for “crime mapping software”, the best I know of this genre is the Chicago Crime Map which is intricately tied to the Chicago PD’s database for its data source.

ChicagoCrimeMap User Interface

Like I said, the possibilities are endless, but the nice thing is this: even if 20 different people are working on 40 different ways of mapping the same thing, the concepts are the same and can be integrated onto one map if necessary. So, what are you waiting for? Get thee hunting and pecking online, see what you can find and report back. Let’s turn New Orleans into another shining example of OpenSource civic intelligence!

Related Links:

Guide to Mostly On-Line and Mostly Free U.S. Geospatial and Attribute Data –> Louisiana

GeoPress for WordPress

Getting Started With Google’s MyMaps – one nice thing is that it generates KMLs which you can then import into Google Earth.

4 comments… add one
  • Citizen Crime Watch March 24, 2007, 2:51 PM

    We’re working on a custom citizen entry form with Ruby on Rails at Citizen Crime Watch, but see, there’s so much going on, I didn’t know about GeoPress. A new toy to play with. Thanks for the tip, and thanks for the publicity. The more people know, the greater are the chances citizens will get that data from the NOPD.

  • Edward Vielmetti March 24, 2007, 10:22 PM

    Thanks for the note Maitri. The core problem is getting accurate and timely data from official sources; once you have that, everything else is a small matter of programming.

    A tool of possible use for scraping pages (as long as we’re talking tool use here, and not exercise of political power, as the way to move mountains) is something called “Beautiful Soup”.


    It’s a Python library optimized for screen scraping, so it will take in ugly pages and help you isolate the bits and pieces that you really want to reuse for your clean database. You hate to resort to that but sometimes you have to.

    This is the blog of the guy who did the Chicago Crime site:


    He’s an investigative journalist for the Washington Post – someone to engage with on all levels of how data can inform people’s understanding of a situation (crime and otherwise).

  • Edward Vielmetti March 24, 2007, 10:35 PM

    Wow, I just looked at the NOPD site and it’s worse than I expected.

    The other way I can imagine to reconstruct useful data out of this mess is to script all of the fetches of the maps at a proper size, and then use some kind of image analysis tool to reconstruct the locations of the crimes in question. You’d be looking to extract the blue blobs and turn them into street addresses or at least geographic coordinates – I’d probably find someone who knew GIMP and feed them some beers and see what they could come up with.

  • Edward Vielmetti April 27, 2007, 8:39 PM

    It turns out that Andrew Turner, one of the Geopress developers, is here in Michigan – had lunch with him the other day. Small world.

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