Defending KML against the proprietary police

Defending KML Against the Proprietary Police

November 23rd, 2005 · 13 Comments · ArcGIS Desktop, ESRI, GIS, Open Source

Link - “Proprietary” Formats: KML and GML

It would appear that the only salient difference in proprietary-ness is that KML was developed by a single company (albeit with input from others), whereas GML was developed by a standards committee. The salient difference in the marketplace is that KML is usable and hand-editable, whereas GML is rather too complex for use without tools. In contrast to what one might expect, the standards committee developed format requires tools to create, whereas the one developed by Keyhole does not.

Strong words against the GML camp, but some of it might be deserved. Personally I’ve not run into too many people complaining about KML being proprietary, but I’ve seen people bring it up on different blogs. As a GIS professional I don’t really care about which formats have OGC standard labels on them as most of our clients use one of 3 formats for data interchange; e00, shapefile or personal geodatabase, all ESRI formats. I don’t see the day anytime soon where KML will get added to that list, but if ESRI continues to integrate KML support into their products and continues to ignore GML it could happen.

I got hammered a months ago about complaining that much of these open formats aren’t supported in ArcCatalog and saying it was up to the open source community integrate into ArcGIS products, rather than ESRI. I think at this point with ESRI OGC support usually limited to an ArcGIS extension, someone needs to step up and write some tools for GIS professionals to integrate OGC support into their ESRI workflows because ESRI doesn’t seem to think it is a priority. There are tons of open source tools that support both OGC and proprietary ESRI standards and formats, but you have to pay money on top of ArcGIS to get such support in ArcGIS. Many look at this as ESRI’s fault and maybe it is, but given all the KML export/import tools being developed for ArcGIS, you’d think someone would take on the challenge and integrate all the GDAL tools into a nice toolbar or toolbox.

[tags]KML, GML, ArcGIS, ESRI, GDAL[/tags]

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13 responses so far ↓

1 Sean Gillies // Nov 23, 2005 at 2:13 pm

James, you’re conflating open standards (OGC) and open source (GDAL) in your last two sentances. ESRI would rather you stick with their proprietary protocols than use W*S. I won’t debate whether that’s right or wrong, but it’s not really related to whether or not people will make GDAL-based products for ArcGIS.
2 James Fee // Nov 23, 2005 at 2:14 pm

Hmm, that doesn’t make a lick of sense. I’ll rewrite it.

I do think it is an issue though. Just publishing a standard doesn’t it make it one. Support for that standard from ArcGIS would go a long way to making that standard stick. People can post about GML till they are blue in the face, but until one can use standard GIS tools such as ArcGIS, it is all theory to most average GIS professionals. I used GDAL as an example, but you’d think there would be an open source extension for ArcGIS that did pretty much what GDAL does, but integrated into ArcToolbox.
3 Dylan Beaudette // Nov 28, 2005 at 10:13 am

I have conflicting feelings about this post. Why should OSS authors write “ESRI-friendly toolbar” interfaces to their applications? One of the greatest features of these OSS applications is the lack of the pointing and clicking nightmare that most modren software has become. In addition, it should be ERSI and its users’ responsibility to integrate any outisde resources into the Arc* applications: what motivation would an OSS author have for spending time on such things?

Perhaps a better suggestion: how about the people currently using ESRI products, and interested in OSS applications, take the time to read the documentation on these applications and use them as they were designed to be used.

Cheers,
4 James Fee // Nov 28, 2005 at 10:30 am

I understand that thinking but there are many places where companies/governments have limited GIS to only ESRI products. Most DoD clients I work with can only have ArcGIS 8.x right now. How can someone working with ArcGIS collaborate with users of OSS and “formats” such as GML?
5 Shayne Urbanowski // Nov 28, 2005 at 1:10 pm

It is commonly accepted that GML is too complicated for some application. This is why the GML Simple Feature Profile was created. This profile is much more “usable and hand-editable”. If the GML Simple Feature Profile did not meet the needs of Google/Keyhole, they could have easily defined a profile of their own. This would make their data format a subset of a larger specification and would make their data immediately consumable by an existing base of applications and API’s. Having a format maintained by a standards organization allows members of the community to have a voice in the enhancements, lifecycle and overall evolution of a format/standard.
6 Brian Flood // Nov 28, 2005 at 1:26 pm

as to GML SFP, either Keyhole wanted to control the standard or the SFP did not exist when they started KML back in 2001-2002 timeframe. I would have prefered GML but its really a moot point, I doubt Google will change now.

IMO, it comes down to ease of consumption. GML doesn’t have a good viewer. KML does and its free to boot.
7 Ron Lake // Dec 22, 2005 at 8:34 pm

The comment “The salient difference in the marketplace is that KML is usable and hand-editable, whereas GML is rather too complex for use without tools.” does not make sense. GML is XML just like KML - in fact KML is GML (geometry, time etc.). The key difference is NOT the grammar but the fact that Google provides a viewer that overlays on a nice image dataset. Take away the image dataset and/or the viewer and what have you got?
8 James Fee // Dec 22, 2005 at 8:39 pm

Ron,

Excellent point, KML is a topic because of the imagery (and that word “Google”) in Google Earth, not because it is a great way of doing anything.
9 Brian Flood // Dec 23, 2005 at 7:18 am

For the most part, I totally agree. Without the viewer and the vast infrastructure powering it, it would not be nearly as compelling. However, there is one aspect of KML that seems to be overlooked in the comparisons. NetworkLinks, the ability to refresh data based on viewable extent or time, is an extremely powerful feature especially when its based on generic Http url endpoints (yea REST!). Should it have been mixed in with geometry primitives and styling information, I don’t know for sure but I’m glad its in there. (Ron - where’s the best spec/explanation for the entire GML namespace?)

cheers
brian
10 Shayne Urbanowski // Jan 10, 2006 at 9:18 am

While searching for additional info regarding GML data and Google Earth I found a
press release that mentions:

“Keyhole demonstrates its commitment to open standards with support for OpenGIS GML V1.1 in Keyhole 2 Pro, facilitating interoperability with GIS deployments.” http://www.keyhole.com/body.php?h=news&t=20040524

Any speculation about what happened to this functionality? I suppose they decided it was not worth maintaining this functionality.
11 Carl Reed // Jan 16, 2006 at 9:44 am

James -

There are actually dozens of GML viewers out there in geo-space. Simply Google “gml viewer”. For example, check out the US gov site http://www.faa.gov/aixm/ If you are looking for lots of information on GML (links, press releases, articles, etc) go to XML Coverpages and search on GML. The OGC will be posting a new GML resource page in the near future.

Cheers
12 James Fee // Jan 16, 2006 at 9:53 am

sure, but unless ESRI allows users to load GML directly into ArcMap I can’t use it. Our clients will never support formats that aren’t used by ESRI by “default”. That isn’t OGC’s problem, but they are affected by ESRI’s poor decision not to support GML right out of the box.
13 matt wilkie // Feb 22, 2006 at 5:28 pm

You can load GML into ArcMap with the free CarbonArc extension: http://www.thecarbonproject.com/products/carbonarc.html (though I’ve yet to try it personally).