gdal-ecw

• Read-only plugin for ECW and JPEG2000 Raster Formats
• Requires gdal and manually-installed ECW 4.2 Runtime libraries
• Write support for ECW and JPEG2000 via the ECW SDK is not available as part of OSGeo4W
• Maintainer is FrankWarmerdam

Installing ECW SDK

The GDAL ECW Plugin requires the ECW 4.2 Runtime library, which is by ERDAS. In order to use the runtime libraries, the end user is required to download and install the DLLs into a system directory.

Download "ERDAS ECW/JP2 SDK Desktop Read-Only Version 4.2" ECWJP2SDKSetup_RO_20110303.exe: ​http://downloads.erdas.com/reqdownload.aspx?guid=53e5b5ff-3591-4dcc-ac74-5aa985ab9ffd.

After downloading and installing the ECW SDK it is necessary to copy the runtime DLLs from the redistributable\vc90\win32\ directory to somewhere appropriate, like C:\Windows\system32 (32-bit Windows), C:\Windows\SysWOW64 (64-bit Windows), or C:\OSGeo4w\bin.

E.g.:

copy "C:\Program Files\ERDAS\ERDAS ECWJP2 SDK Desktop Read-Only\redistributable\vc90\win32\*.dll" C:\Windows\system32

Or on a 64-bit version of Windows:

copy "C:\Program Files (x86)\ERDAS\ERDAS ECWJP2 SDK Desktop Read-Only\redistributable\vc90\win32\*.dll" C:\Windows\SysWOW64

Note that downloading and installing these DLLs requires agreeing to a license. Please review the license terms carefully.

It is imperative that the VC9 ECW 4.2 SDK binaries be used. Any other ECW (NCS*) DLLs are unlikely to work properly. However, it's reported that 4.1 SDK ECW DLLs seem to work as well.

Failure to install the correct ECW libraries will normally result in a popup message reading "This application has failed to start because NCSEcw4_RO.dll was not found." or a console error report like:

C:\warmerda>gdalinfo
ERROR 1: Can't load requested DLL: C:\osgeo4w\bin\gdalplugins\1.9\gdal_ECW_JP2ECW.dll
126: The specified module could not be found.

ERROR 1: Can't load requested DLL: C:\osgeo4w\bin\gdalplugins\1.9\gdal_ECW_JP2ECW.dll
126: The specified module could not be found.

Usage: gdalinfo [--help-general] [-mm] [-stats] [-hist] [-nogcp] [-nomd]
                [-norat] [-noct] [-checksum] [-mdd domain]* datasetname