GeoServer and GeoSolutions @ gvSIG Days 2011

GeoSolutions will attend the 5th edition of the gvSIG Conference, organized by the Regional Ministry of Infrastructure and Transport (CIT) from December 2nd until December 4th at the Feria Valencia Convention and Exhibition Center.  

Ing. Simone Giannecchini will provide an introductive workshop on GeoServer, therefore make sure you take note of the exact time on the conference program and you make room in your schedule for attending the event.
Check this link for more details.

See you in Valencia!

The GeoSolutions team.

GeoServer e GeoSolutions al GFOSS Day 2011

GeoSolutions sarà presente alla conferenza GFOSS DAY 2011 che si terrà a Foggia il 24 e 25 Novembre presso la Università degli Studi.



Oltre ad essere sponsor Silver della manifestazione, GeoSolutions sarà presente con un workshop gratuito introduttivo ed una presentazione su GeoServer che si terranno entrambi nella giornata del 25 (si veda per dettagli il programma della manifestazione).

Quindi, se volete essere aggiornati sugli sviluppi del GeoServer o se volete essere introdotti al suo utilizzo da uno dei suoi creatori non vi resta che farci visita a Foggia!

The GeoSolutions team.

ImageI/O-Ext 1.1.2 Released

Dear all,
GeoSolutions is pleased to announce the ImageI/O-Ext 1.1.2 release. With respect to 1.1.1, it adds a few bug fixes as well as improvements for the Tiff reader as well as on how we manage file memory mapping to provide a nice performance boost on remotely mounted file systems, e.g. NFS.
Release artifacts have been deployed on the GeoSolutions maven repository, as well as on the OSGEO one.

It is worth to notice that we are right now discussing with the GeoServer community for switching the GeoServer 2.1.x branch to this new ImageI/O-Ext release (the unstable trunk version already leverages on this newest ImageI/O-Ext) .

If you have questions about ImageI/O-Ext or if you want to know more about our services could help your organization to reach its goals, do not hesitate to contact us.

Regards,
the GeoSolutions Team

ImageI/O-Ext 1.1-RC1 Released

Dear all,
GeoSolutions is pleased to announce the ImageI/O-Ext 1.1-RC1 release which has been incubating for a long time.
Changes with respect to 1.0.x series can be summarised as follows:

• Out-of-the-box Support for GDAL 1.7.3, which means no more patches are needed for GDAL Java bindings in order to access it from ImageI/O-Ext.
• BigTiff support, breaking the 4GB TIFF limit.
• EnhancedImageReadParam support. It extends the standard ImageReadParam by implementing Cloneable (used when supporting MultiThreading read operation) and a new DestinationRegion param to support oversampling/subsampling without specifying sourceSubSampling parameters. This may be used when dealing with readers which internally take care of performing subSampling/overSampling, such as the GDALImageReader
• Experimental multidimension plugin for reading spatiotemporal sources like:
• netCDF raster files following the Climate and Forecast (CF) convention
• GriB edition 1
• HDF version 4

Release artifacts have been deployed on the GeoSolutions maven repository, as well as on the OSGEO one.

Regards,
the GeoSolutions Team

WorldFile explained (or at least we tried!)

There is a lot of confusion around about what world file represents therefore we thought it would have been nice to put together a couple of clarifications.


The World File
World File is a de-facto standard from early days of ESRI desktop GIS applications. Originally it was composed by at least two files, a raster file, let' say a file.tiff,  and another file (most part of the times called file.wld)  that contains numbers that define the affine transformation between the image and the target spatial reference system. This implicitly means that we are talking about georectified raster data. This wld file is what should be properly called the world file. Other extensions that could be used on behalf of tfw are wld tifw, etc... Moreover some other formats beside tif can be used, like gif, png, jpeg, jpeg2000, etc..and the extensions for the world file become pretty fancy (gifw, pgw, etc..).

The concept behind this couple is as follows. An image (e.g. a tif) plus its world file represent a geospatial georectified raster in some spatial coordinate reference system (CRS). The mapping between the raster space (the intrinsic Image space of rows and cols) and the associated model space is represented by an affine transformation whose coeffficients are contained inside the accompanying world file (see here ). This way, practically any image format can be made spatial-aware just adding a world file containing an affine transform that maps image points onto a crs. Here is a good explanation of what a world file contains.

The Projection File
One would now ask, ok, but what coordinate reference system I am supposed to use. The best answer would be "the one the person who produces the image + the world file was using"! Seriously many people make assumptions on the CRS used for the georeferencing affine transform contained in the world file, but in fact this can lead to all sort of problems. The best way to transmit the information about the spatial coordinate reference system is providing a third file with extension prj which contains the well known text (WKT more info can be found here) representation of the user spatial CRS. The Spatial Reference website can be extremely useful for associating the proper WKT to a certain CRS.


Recommendation
Notice that usually the raster space has x going right and y going down while in model space things DEPEND on the spatial CRS, specifically, axes order and axes directions!
ALWAYS ASK YOUR DATA PROVIDER TO DESCRIBE EXACTLY THE SPATIAL COORDINATE REFERENCE SYSTEM THAT WAS USED TO GEOREFERENCE YOUR DATA.

The GeoSolutions Team,