Latest on JPEG2000 Improved Support for the Java world

Dear all,
We would like to take the occasion to describe more in details some improvements that were implemented with the ImageI/O-Ext 1.0.8 release (which is now supported by GeoServer 2.0.2, 2.7.x and GeoTools 2.6.4 and 2.7.x) as well as with the previous ones.

Reader Improvements
Various improvements have been implemented for the JPEG2000 Kakadu reader in order to enhance its speed and robustness:

• More checks on stripe decompression
• Improved Warning Messages at startup
• Improved subsampling factor computation 

Writer Improvements
Various improvements have been implemented for the JPEG2000 Kakadu writer in order to enhance support for very large imagery writing in terms of more control options as well as in term of reduced footprint during the writing process itself.
Specifically we have added the following:

• Support for writing the GeoJP2 box
• Support for writing tile oriented images
• Support for Corder
• Support for ORGgen_tlm
• Support for ORGgen_plt
• Support for ORGt_parts 

Sample Code
At the following link you can find an example that tells you how to read/write JPEG2000 data using ImageIO-Ext:
http://pastebin.com/uY2n17Gz

ArtifactsReleased
Artifacts for Imageio-Ext have been deployed on the GeoSolutions maven repository, as well as on the OSGEO one.

Regards,
the GeoSolutions Team

GeoServer and GeoTools now supporting JPEG2000 via Kakadu SDK

Back in December 2009 Ing. Daniele Romagnoli and Ing. Simone Giannecchini have worked on bringing to supported status the raster plugin for serving JPEG2000 files via the well-known Kakadu SDK in GeoTools and GeoServer. A detailed description of the feature provided can be found here.

The rationale behind this work was to be able to exploit directly the Kakadu SDK without having to pass through the GDAL Java wrappers in order to achieve higher performance and robustness as well as to gain finer control over the steps we were taking in order to load raster data from JPEG2000 files.

The plugin for GeoServer 2.0.1 and GeoTools 2.6.1 is known to work with Kakadu SDK 5.2.x as well as 6.3.x. It is available as an extension, therefore can be downloaded from here (look for Extensions then Coverage Store then JPEG2000). To install it, instructions are as follows:

• 
  Download the plugin zip file for the same version of GeoServer
  
• 
  Unzip the plugin zip file to obtain the jar files inside. Do not unzip the jar files
  
• 
  Place the jar files in the WEB-INF/lib directory of your GeoServer installation
  
• 
  Restart GeoServer to load the extension
  
• 
  It is important to remark that the native libraries for the Kakadu version of choice must be deployed in the PATH on windows and in the LD_LIBRARY_PATH on linux. As an instance on my Windows box I have added the bin directory of the JDK to the PATH environmental variable and I have deployed there three dlls for Kakadu 5.2.6, namely kdu_a52R.dll, kdu_jni.dll and kdu_v52R.dll
  

In order to check if the installation was successful you need to check the GeoServer logs at startups. If something like this appears:

18-feb-2010 17.11.15it.geosolutions.util.KakaduUtilities loadKakadu
WARNING:Native library load failed.java.lang.UnsatisfiedLinkError: no kdu_jni in java.library.path

It means that the Kakadu JPEG2000 extension was not installed correctly.

To give you an idea of the speed up we have obtained, I am reporting here the numbers of some testing we have performed on our test server, using the WMS performance shooting approach. Sample dataset was a mosaic of 4 JPEG2000 files (GeoJP2 actually) of around 200 MB each.
We have compared the latest GDAL extension for GeoServer based on a customized version of GDAL 1.4.5 with our plugin running on top of Kakadu 5.2.6 and 6.3. As far as GDAL is concerned, we have been using the MrSid SDK, the ECW SDK as well as both Kakadu versions reported above. Numbers are asfollows:

Requests served via GDAL

Jp2Kakadu 5.2.6	6/min
Jp2Kakadu 6.3	11/min
Jp2Mrsid	12/min
Jp2Ecw	35/min

Requests served with no GDAL- using Kakadu directly

Kakadu 5.2.6	120/min
Kakadu 6.3	222/min

These numbers are not scientifically measured, but we think they show some nice performance improvements.
What we need now is feedback from the community!