[gdal-dev] Re: GDAL drivers written in Python

[Antonio Valentino]

Hi Knut-Frode,

Il giorno Thu, 07 Apr 2011 12:03:24 +0200
Knut-Frode Dagestad <knutfrodesoppel at hotmail.com> ha scritto:

> Antonio,
> 
> On 06.04.2011 13:09, Antonio Valentino wrote:
> > I'm not sure to understand. GDAL reads data from the product. If the
> > product is not geo-referenced you will get data that are not
> > geo-referenced.
> >
> > In this case you could use GDAL tools to interpolate data in a
> > geographic grid but you need to know geographic info and/or
> > parameters that are stored in the product itself.
> >
> > In the case of ENVISAT product (but for stripline ones #3160) you
> > should be able to perform the re-projection e.g. using gdalwarp with
> > the -tps option (I never tested it personally).
> 
> It could be that I do not properly understand the term
> "georeferenced". For the example of Envisat ASAR, the image data is
> read perfectly, and also GCP's are read relating rows and columns to
> latitude and longitude (though not correct, #3709).
> When the datum is given (WGS84) should this product then not be 
> georeferenced?

Oh sorry, my english is very poor.
I used the term "georefernced" to intend products that are sampled on a
regular geographic grid, oriented to north, etc. (e.g ENVISAT IMG
products).
Products like ENVISAT IMS or IMP have an associated reference ellipsoid
but are not sampled on a regular geographic grid.


> Nevertheless, Envisat is marked as not georeferenced in the table of 
> supported raster formats, and reprojecting with gdalwarp does also
> not work for me.
> 
> >> Finally, we would also ideally like to have immediate (pre release)
> >> support for upcoming satellites such as the ESA Sentinel
> >> satellites.
> >
> > This is very interesting.
> > Can you point me to product specifications of Sentinel data?
> 
> I have not looked at this yet, but is seems like the format for 
> Sentinel-1 will be Geotiff and XML, so it should then not be a
> problem at all:
> http://www.terrafirma.eu.com/Documents/Workshops/WS%206/ESA%20SAR%20Products%20for%20Interferometry.pdf
> 

Thank you very much

> 
> Best regards from Knut-Frode
> 
> _______________________________________________
> gdal-dev mailing list
> gdal-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/gdal-dev



-- 
Antonio Valentino