Collaborating in geospatial context since 2000!

Thursday, July 10, 2008

On GeoPDF

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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4 Comments:

Anonymous Anonymous said...

Global Map Systems now provides a product that sparks my interest...A LOT!

Could you please respond with what your strategy is related to this competitor's product?

It looks like they are touting it as a GIS with analytic capabilities, not just a "viewer"; this is a difference, correct?

I'm sure I won't be the only one to say to you in the near future "why don't you offer that function in your toolset?"

Would it be good for TerraGo to respond with product enhancements that meet or beat this competitor's offerings?

For example, after reviewing the product, I can note specific functions that are far superior to your GeoPDF Toolbar functions.

Pros:
-Cost (a lot cheaper)
-Identify (not available with GeoPDF)
-Find (also not available with GeoPDF..you can't query attributes per layer per field, that is)
Export (really cool!)
Statistics (even cooler!)
Frequency (nice analysis!)

Cons:
New
Unknown/Untested
Will only function within Acrobat, not the free Reader, yet. This fact is very good for TerraGo! Actually, this may be the TerraGo "life saver", for now.

Specifically, I'd appreciate it if you could tell me how/if you plan on enhancing your functions to match this competitors "Pros" I list above?

Thanks!

10:07 AM EDT

 
Blogger Adam Estrada said...

After briefly investigating the Global Map Systems ArcGIS extension, it is apparent that you get what you pay for! The system requirements are strict and the performance is flaky at best. The product seems to do all the work by launching Acrobat in the background and because the machine this was being tested on is a slug, there were multiple issues with poor performance and maxed out memory usage.

Their toolbar was grayed out and for the life of me I was not able to get it to appear. I think that it was because there was a 6 gig raster data set in the background but I'm not sure so don't quote me on that.

Another key point here was that after generating a PDF, ArcGIS had to be restarted because the single button to start the tool basically quit working. This probably has to do with the way the software handles instances of Acrobat running in the background.

Processing times are brutally slow and when I tried to create a PDF with 35,000 line features, it took about 27 minutes. This is the data I always use from the Cobb County GIS department here in Atlanta. This was a free download for anyone and its kinda funny that the data I have been testing with is from the same county that TerraGo and GMS are both located in.

I think that at this point I will try to put together a full analysis of this as compared to ours. I will update the blog accordingly...

4:57 PM EDT

 
Blogger Adam Estrada said...

Oh and please read the latest blog post:

http://geopdf.blogspot.com/2008/09/spatialite-22-release-update.html

This was meant to elude to things to come.

4:59 PM EDT

 
Blogger George Demmy said...

Dear Anonymous,

It's great that you find the GMS offering compelling. I would be
curious, however, to understand why you find it more compelling than, say, ArcGIS, or ArcPad, for that matter? If what you want is a pocket GIS, then why mess about with shape files in PDF clothing? ArcGIS delivers exceptional GIS functionality.

If there is some business need that is solved by the statistics and frequency functions, please let me know and I'll roll it into our product requirements. If all you want to do is skin shape files with PDF, please let me know why and we'll ratchet up the priority.

Our Map2PDF for ArcGIS product is first and foremost an composition tool. We empower people to enhance the cartographic representation of
their data and make it more accessible to their audience or to anyone using Adobe's free Reader. If they have our free Toolbar, then so much the better. It also allows the ArcGIS user to view the mark-ups made by end users in the context of the original map. The georegistration aspect is just enabling technology which is now free and open to anyone.

If you're fretting about kurtosis, I'm the first to admit your needs might well be better met by ArcGIS or Mathematica than our Toolbar. Our attention is focused on linemen and warfighters and volunteers counting eggs in turtle nests.

Our current product roadmap has on it ad hoc, peer-to-peer collaboration and creation of geospatial applications tailored to
specific business needs. Without further context, I don't instinctively find the pros you enumerate particularly compelling -- and this coming from someone for whom PDF means probability density function. Please convince me otherwise! I would genuinely like to know what you need from our products to help you get your job or the jobs of those you serve done.

Regards,

G

8:45 AM EDT

 

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