[gdal-dev] Re: GDALwarp - Too many points (441 out of 441)

[WolfgangZ]

Frank Warmerdam schrieb:
> Thomas Becker wrote:
>> Hello listers,
>>
>> i am new to GDAL and have a problem to warp a GeoTiff.
>> The projection of the GeoTiff i got is shown in QGIS as
>> '+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs'
>> but the info file from the department says
>> ETRS89/ UTM 33 Ellipsoide GRS80.
>>
>> Now i was trying to use gdalwarp with
>>
>> gdalwarp -s_srs '+proj=longlat +ellps=WGS84 +datum=WGS84' -t_srs
>> '+proj=utm +zone=33 +ellps=GRS80' input.tif output.tif
> ...
>> I will add the gdalinfo output:
>>
>> Driver: GTiff/GeoTIFF Size is 10000, 10000 Coordinate System is `'
>> Origin = (33360000.000000000000000,5972000.000000000000000) Pixel Size =
>> (0.200000000000000,-0.200000000000000) Metadata:
> 
> Thomas,
> 
> The above coordinates do not appear to be UTM 33 (much less lat/long
> decimal degrees).  Specifically with an X origin of 33 million you are
> either using a world projection (the world is roughly 40 million meters
> around) or you are measuring in some alternate units like centimeters.
> 
> Basically, you need to find out what coordinate system you are working
> with before you can meaningfully proceed.
> 
> My offhand guess would be that you are using Plate Caree with a false
> easting such that the origin is at the dateline instead of the greenwich
> meridian.  But that is a shot in the dark.
> 
> PS. I hate playing "please guess my coordinate system" games.
> 
> Best regards,
just  a guess: can it be that your x values have the UTM zone printed 
before the actual x value comes? Than you need to get rid of these two 
numbers. One way would be to translate your image to the vrt format 
(this gives only a text file with the geographic description of the 
image which you easily can edit. Than you use the vrt file as input for 
your warping.

regards
wolfgang