How do I make ECW files work in Quantum GIS?

[whoopn]

I would really like to understand how to make ECW files (they are images files that can be terabytes in size but easily opened) viewable in Quantum GIS.

I found this on the QGIS forums:
http://forum.qgis.org/viewtopic.php?p=283
You have to download the ECW SDK from http://www.ermapper.com/
Then apt-get source gdal
Then edit debian/rules and add the following configure switch:
--with-ecw=ARG Include ECW support (ARG=ECW SDK Path, yes or no)

Then rebuild the package with dpkg-buildpackage -rfakeroot
You may find the apt-build package useful for this.

I don't quite understand what they are talking about... Can anyone explain (in more complete instructions) what is going on and how I accomplish this?

Thank you so much! If we get this stuff working in Ubuntu then my office will most likely switch to Ubuntu! :)

[Nick Lake]

I know this is an old thread... but thought I'd reply anyway.

ECW - Enhanced Compression Wavelet format was created by ER Mapper (now Leica Geosystems). Products like ER Mapper can export to ECW (not sure if they support Linux - but all of their software used to run on UNIX). There are also a number of free compressors but these are usually limited in the size of the data they can compress.

Other compression formats you may want to look at are:
1] MrSID from LizardTech (also uses wavelet compression).
2] JPEG2000

- Nick Lake

[lutra]

I would really like to understand how to make ECW files (they are images files that can be terabytes in size but easily opened) viewable in Quantum GIS.

I found this on the QGIS forums:
http://forum.qgis.org/viewtopic.php?p=283


I don't quite understand what they are talking about... Can anyone explain (in more complete instructions) what is going on and how I accomplish this?

Thank you so much! If we get this stuff working in Ubuntu then my office will most likely switch to Ubuntu! :)



you need to compile from source, including the SDK you need. I wrote a guide for the local GFOSS community, so it is in Portuguese, but you should understand quite well the steps.

I wrote the guide for Qgis 0.10 but you can apply it also to the 0.11 version and even the upcoming 1.0


http://wiki.osgeo.org/wiki/Instalar_Grass_e_Qgis_em_Ubuntu_8.04_(com_ECW_e_Mr SID)


take care