Collaborating in geospatial context since 2000!

Monday, July 28, 2008

SpatiaLite: An Alternative Spatial Database

We all know about ESRI's Personal GeoDatabase (MS Access), Refraction's PostGIS, Oracle Spatial, etc... but how many folks are familiar with SpatiaLite? SpatiaLite is the spatial extension to SQLite and after a few initial rounds of testing, I think we have a decent light-weight alternative to the bigger players in the spatial DB game.

First off, what is SQLite?
SQLite is a software library that implements a self-contained, serverless, zero-configuration, transactional SQL database engine.

SQLite is the most widely deployed SQL database engine in the world. It is used in countless desktop computer applications as well as consumer electronic devices including cellphones, PDAs, and MP3 players. The source code for SQLite is in the public domain.
This means that the SQLite engine is deployed in more computing environments than any other database technology in the world.

Alessandro Furieri, the author of SpatiaLite and VirtualShape, created these extensions knowing this! Good job Alessandro!

The latest release of SQLite will include better R-Tree indexing and a wide variety of other enhancements that conform to the OpenGIS Standard for Spatial Data Processing. See below for the SpatiaLite 2.1 Quick Intro.
  • SQLite is a popular DBMS, simple, robust, easy to use and really lightweight
  • each SQLite database is simply a file; you can freely copy it, compress it, send it on a LAN or WEB with no complication at all
    They are also portables; the same database file will work on Windows, Linux, MacOs etc
  • the SpatiaLite extension enables SQLite to support spatial data too [aka GEOMETRY], in a way conformant to OpenGis specifications
    • supports standard WKT and WKB formats
    • implements SQL spatial functions such as AsText(), GeomFromText(), Area(), PointN() and alike
    • the complete set of OpenGis functions is supported via GEOS, this comprehending sophisticated spatial analysis functions such as Overlaps(), Touches(), Contains() and so on
    • supports full Spatial metadata along the OpenGis specifications
    • supports importing and exporting from / to shapefiles
    • supports coordinate reprojection via PROJ.4 and EPSG geodetic parameters dataset
    • supports locale charsets via GNU libiconv
    • implements a true Spatial Index based on the still experimental SQLite's RTree extension
  • the VirtualShape extension enables SQLite to access shapefiles as VIRTUAL TABLEs
    • you can then perform standard SQL queries on external shapefiles, with no need for importing or converting them
  • the GUI tool supports all this, in an user friendly way
How to get started with SQLiteGeo (SpatiaLite, VirtualShape, and SQLite3 combo):
  1. First, try downloading SQLiteGeo. Simply download the ZIP file or Linux Version and extract it anywhere on your local file system.
  2. Follow the tutorial to import, index, and analyze your data.
Version 2.1 GUI Tool:
  1. There is also a GUI tool that will keep you from having to go through the command line. Click Here for all available options!
  2. Download the Windows version here and the Linux version here. Extract the files to your local system and go! There is no installation...
Also, try the SQLite ODBC Driver. I have been able to import/export data through Access and Excel without very many problems.

I'm certain that there are a wide variety of uses for this self contained, file-based, spatial database technology so please feel free to comment on any interaction you may have had with it.

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Wednesday, July 23, 2008

Multi-band Raster GeoPDFs

Over the past few months, the raster team has been working hard to iron out the plans for the next generation of Map2PDF for Raster. There have been many interesting developments that have come out of it like adding the ability to query for and display more than just 3 bands of base data at a time. I posted an article about creating a GeoPDF out of AVIRIS data with 224 bands and got mixed reviews as to why this would be useful. The problem was with the way we used Adobe's blend modes when interactively turning visual bands on and off in Adobe Reader. There are quite a few blend modes to choose from and most of them are not applicable to the world of GIS and Remote Sensing! It's ok though as we have found a couple methods that work and are actually pretty useful.
  1. Difference: Subtracts the darker of the two constituent colors from the lighter color (which is the background for the PDF).
  2. Exclusion: Produces an effect similar to that of Difference mode but lower in contrast.
In previous examples, I used blend modes that completely covered the base map data with other bands of sensor data. The Hyperspectral example was ultimately botched because of this. Well...that and we were not stretching the histogram for each band added after the RGB base map.

The graphic that you see below represents a very small QuickBird scene with an IR band that is displayed as Band 4 in the Layers Tab. Open the PDF and click on the Layers Tab to see how blending modes are implemented in the PDF space. This PDF was created with low image quality to save space!

Download the GeoPDF Toolbar to gain access to all the spatial information!


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Monday, July 21, 2008

Gigapan and Global Connection

Gigapan is an interesting project to say the least and it looks like the Global Connection Project is making full use of the technology. Commercial Gigapan is a robotic camera mount that creates these panoramas that (starting in August) can be uploaded and compiled for free! They also mention that this will be released as an open source project which is cool too...
Check out the impressive list of folks contributing to the Global Connection Project. I always end up coming back to which was developed by Paul Neave who is also noted as a team member for the Global Connection Project. The Gigapan viewer is a flash app that I suspect Paul had a lot to do with. Because this is a Flash viewer, we can take it to the web as well as to the desk top through applications like Acrobat 9.0 and Google Earth.

Pretty soon, we will not have to leave the house for vacation!!! We will be able to visit anywhere on earth via a Google application.

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Thursday, July 17, 2008

ERDAS Image Web Server

Do you own large amounts of raster data? The ERDAS Image Web Server is a COTS solution that easily allows your organization to quickly integrate raster data in to your GIS. ESRI has a similar solution in the ArcGIS Image Server but wouldn't it be more adventageous to manage your raster data through a product whos main focus is the speedy delivery of large volumes of raster data? There are pros and cons to both products I'm sure...for example, both applications provide a way to extend the core functionality. ESRI gives you an API (more than likely through ArcObject programming) while ERDAS gives you the Image Integration Framework. I would be really interested to see a side by side comparison for both!!! NOTE: Leica (now ERDAS) acquired ERMapper last year.


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Friday, July 11, 2008

GeoEye-1 Launch Announcement

GeoEye-1 is set to launch on August 22, 2008 and it looks like this satellite is going to surpass the imaging capabilities of IKONOS and QuickBird. We on the commercial side will get half meter resolution while the DoD folks get about 16 inches with a return time of <3 days. It will also collect in three camera modes, panchromatic only, multispectral, and then simultanious panchromatic and multispectral (pan-sharpened). It looks like it will also collect in stereo...

Hopefully, data on the commercial side will be affordable or at least help to drive its competitors to lower their prices! Visit the GeoEye website for more details...

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Thursday, July 10, 2008


GeoPDF is, always has been, and always will be PDF. It has its roots in publishing utility drawings in different to utilities operations and maintenance field workers to PDF file sets augmented with feature data and convenient navigational features derived from different databases and other data stores. In order to place things like hyperlinks to detail drawings on a map, we had to derive the relationship between the real world location of some item of plant and the corresponding location on the PDF page.

Once this association can be made, it's relatively straight forward to generalize it. There a bunch of ways to skin that cat, we chose a georegistration technique that relates the PDF coordinate system to a projected coordinate system similar to the way it's done in GeoTIFF. Just as GeoTIFF uses TIFF constructs to embed georegistration metadata, GeoPDF uses PDF constructs to embed georegistration metadata. Emacs and a GeoPDF file reveals all. Just as GeoTIFF *is* TIFF, GeoPDF *is* PDF.

Our georegistration technique was designed for internal use and compatibility with internally-developed tools and libraries -- not with standardization in mind. As things happen, our customers liked the tools we made for our projects and the powers-that-be declared we'd be commercializing our tool set.

GeoPDF remained proprietary for pragmatic reasons -- it wasn't praticable for standardization and we didn't have the bandwidth to drive the standardization process. Moreover, it's obvious to anyone in the space -- including us! ;) -- that the days of proprietary formats have passed and at some point a well-documented standard would be promulgated. Although the PDF specification is now "owned" by ISO as ISO 32000, Adobe is still the primary shepherd of PDF, and has promulgated an open 2.0 version of our georegistration technique. Adobe is the right company to drive the standardization process -- not TerraGo -- but we're going to help in any way we can. They've done a great job with it and have done some clever things and I'll review the technique in detail when I get back from floating down the Green River in a couple of weeks. We are ecstatic that Adobe has validated our vision of ubiquitous access to geospatial information with their extensions to ISO 32000 and are working hard on having all of our products support it. Moreover, we are thrilled that ESRI has validated in the marketplace what we've been saying all along -- people other than GIS users need access to geospatial information.

Georegistration is enabling technology -- not an end in itself. Adobe is providing a platform for the development of geospatial applications on top of their technology. We've been building such "GeoApps" for almost a decade and working closely and collaboratively with Adobe [PDF] for a long time.

To get overly hung up on GeoPDF as some sort of file format is to miss what it's all about: letting professionals who don't grok GIS use geospatial information effortlessly to get their jobs done. If people don't know that they're using geospatial information on their way to making the right decision then we're doing our job.

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Monday, July 07, 2008

TerraGo + Adobe = GeoPDF

TerraGo Technologies and Adobe announce their partnership today! The following is directly from the press release...

TerraGo Technologies Announces Geospatial Alliance Agreement with Adobe ATLANTA, GA – July 7, 2008 – TerraGo® Technologies, the visionary provider of tools, technology and know-how for building collaborative geospatial applications (GeoApps), announced today that it has signed an Alliance Agreement with Adobe Systems Incorporated. As part of the agreement, Adobe will provide support for TerraGo’s GeoPDF® in the new Adobe Acrobat® 9 software. In addition, TerraGo will fully support consumption of geo-enabled PDF files from Adobe and other vendors, allowing customers to easily build and deliver GeoApps for use by anyone, anywhere, regardless of data format or application source. “Our expanded relationship comes at an exciting time when the demand for geo-enabled PDFs and GeoApps is increasing significantly,” said Richard M. Cobb, president and CEO of TerraGo Technologies. “In working with a global leader such as Adobe, who provides the best platform for geospatial documents, we are confident customers will benefit greatly through the development of innovative new geospatial tools and technology. This alliance further demonstrates TerraGo’s commitment to providing collaborative solutions that meet the unique needs of geospatial data users who are often not GIS experts.”

“As long-time developers of solutions on the Acrobat platform, TerraGo has for several years delivered value to customers who need to consume geospatially-enabled documents in a widely available format,” said Rick Brown, director of Acrobat product management, Business Productivity Business Unit, Adobe. “With support for consuming GIS attributes in PDF now natively available in Acrobat 9 and Adobe Reader 9, TerraGo’s solutions will be even more broadly accessed by existing and new customers alike.”

TerraGo, now a Gold Level Adobe Partner and Adobe LiveCycle™ reseller, expects to further expand its geospatially enabled offerings through close integration with the rich capabilities of the LiveCycle suite of server products.

Click here for full details...

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Wednesday, July 02, 2008

Acrobat Reader 9.0 Released!

Install the latest and greatest Acrobat Reader today! To view the feature comparison chart click here.

This marks the beginning of some really innovative mapping technology! More to come...

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