Gdal with ecw

[Sébastien Legrand]

Hello,
I would like to know why you removed ecw support from GDAL build.
And what can I do in order to make this work.

Thank you

[Jeff McKenna]

Hello,

There is a long history behind the changes to the ECW SDK licencing over the years (made by ERDAS, now "Hexagon Geospatial"), and its affect on downstream software. Some reading for you:

• MS4W's old bugzilla ticket: ​http://bugzilla.maptools.org/show_bug.cgi?id=2037
• interesting licensing discussion in 2010: ​http://osgeo-org.1560.x6.nabble.com/GDAL-1-7-preliminary-package-available-tt3767046.html#a3767065
• interesting GeoServer discussion on licensing in 2009: ​http://osgeo-org.1560.x6.nabble.com/ECW-license-changed-td3828331.html
• GDAL's buildhints page for ECW listing many issues and SDKs and differences (I also help maintain this page): ​https://trac.osgeo.org/gdal/wiki/ECW

You can see that over the years the licensing of the ECW SDK varies, and affected many other software packages using it.

To add ECW support back into MS4W, likely some research needs to be done (possible to use the old SDK with patches, or use an updated 5.x SDK which has limited capabilities due to licensing, and make it work with the latest GDAL).

There is easily a few days to a week of work here getting all this to work in the MS4W build environment. It would be great to have your organization help fund Gateway Geomatics to add ECW support back into MS4W. Please contact me directly if you can help with funding, this would be a great addition for the MS4W community.

-jeff

[Sébastien Legrand]

Thank you for your quick reply.
I recompile GDAL with the support of ecw with the 5.1 SDK. And it works. :)

But before put it into production I will have to do more research.
I didn't know about the new licensing.
We are using Mapserver in an open source software so maybe we can still use it.

I just read that from ​http://www.gdal.org/frmt_ecw.html :
The ERDAS ECW/JP2 v4.x and v5.x SDK is only free for image decompression.

We just want to read ecw, so it may free for us.

[Jeff McKenna]

ok, I was assuming your request was related to MS4W, I misunderstood. If you have any more questions please ask on the MS4W mailing list (subscribe at ​http://lists.ms4w.com/mailman/listinfo/ms4w-users).

Closing.