[gdal-dev] Envi driver and complex dataset

[Julien Michel]

Dear Gdal developpers,

Yesterday I was trying to read my favourite radar dataset, consisting in
a raw file along with an ENVI style header with gdal 1.6.2. I was very 
confident since it was working perfectly fine with earlier version of gdal.

But this time, I only managed to get this error message from gdalinfo:

ERROR 1: The file does not have a value for the data type
that is recognised by the GDAL ENVI driver.

So I took a glimpse at my header file, which is using 6 as a data type,
the right data type code for my complex dataset.

I took a walk into gdal source code in order to try to spot the error
and I came up with these lines (frmts/raw/envidataset.cpp:1791):

/*  Removed JBP, ITT-VIS 11/29/2007.  Complex data does not display
properly in the ArcGIS application so we are removing it from the
supported types list. This is a bit of a big hammer as it may remove
functionality from some direct GDAL users, but this data is extremely
problematic from an ArcGIS standpoint.   */
/*          case 6:
             eType = GDT_CFloat32;
             break;

             case 9:
             eType = GDT_CFloat64;
             break;
*/

So this is it. No wonder why I can not use my dataset anymore. I must 
say that I'm very surprised that every gdal users looses a valuable (SAR 
users will agree for sure) supported dataset types just to accomodate 
one software which is not able to display complex data.

Is it possible to do something to get these types back to working properly?

Best regards,

Julien
-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Julien MICHEL - Ingénieur d'études - Traitement d'images
CS Systèmes d'Information - Division ESPACE
Département Information Géographique & Image
Téléphone : +33 561 17 64 27
Email : julien.michel at c-s.fr

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~