[Gdal-dev] need tools for TIF image reprojection

[Petteri Packalen]

Hi,

This just a guess: what version of GDAL are you using? I had similar kind 
of problem about one month ago before I left to summer holiday. I 
downloaded the newest FWTools version and when I tried to transform some 
images from Finnish kkj to EUREF FIN coordinate system datum shift was not 
applied. EUREF FIN is basically ETRS89 / UTM 35N. When I revert back to 
FTTools alpha 6 everything worked propely. I don't remember what was 
actual gdal versions in these FWTools releases. Please try FWTools a6 if 
possible.

I didn't remember to fill a bug report. I will look at it later when I 
come back to office.

Best regards,
Petteri

On Fri, 14 Jul 2006, Zhonghai Wang wrote:

> Hi Andrew,
>
> you are right, in the most cases the GDAL utilities work well, and I've also
> use the GDAL utilities for a long time, especially the FWTools made by
> Frank, we should all thank Frank for such a wonderful GIS toolkit.
>
> I've check again and again with the GDALWARP, but things are not going in
> the right way. I am trying to translate the TIF images from the coordinate
> system CH1903 (Swiss National System) to ETRS89 / UTM ZONE 32N, and there
> are always  some displacement with the base maps, I am sure that the base
> map and the original coordinate info for the TIF is correct. and here is an
> example:
>
> (the transforming process is : CH1903 -> WGS84 -> ETRS89 / UTM ZONE 32N)
>
> the TIF image coordinate Info (*.tif): (Swiss National System)
> 0.500000
> 0.000000
> 0.000000
> -0.500000
> 598125.250000
> 199999.750000
>
> If I transform the coordinate to WGS84 with GDAL, the value is:
>
> 0.0000059839
> 0.0000000000
> 0.0000000000
> -0.0000059839
> 7.4149523128
> 46.9529994915
>
> but the lon/lat of the upper left corner should be:
>
> 7.41401039348263
> 46.9510762167473
>
> I would say that this is already big difference, because If I use this
> lon/lat to get the UTM coordinate, this small difference will be propagated,
> and will cause a displacement about hundreds meters.
>
> I am trying to find the source code, which does this coordinate
> transformation, so that I can check if the transformation parameters are
> correct, but unfortunately I can not find the source for this.
>
>
> If someone has done something similar, please point me out how to fix this
> problem, especially the GIS people in Switzerland. I would really appreciate
> it.
>
> zhonghai
>
> On 7/14/06, Andrew Williams <awilliams at rapidmap.com.au> wrote:
>> 
>> zhonghai,
>> I've litterally translated hundereds of TIF's from all over the world from
>> multiple projections to multiple projections. I have also had "failures".
>> However, in every case, it was either my fault in specifying the -s_srs or
>> -t_srs. In some cases the fault lay in the original image. The TIFF itself
>> was supplied with incorrect georefernceing information and so it was never
>> going to work.
>> 
>> Have you got a dump from GDALINFO that we can see and the GDALwarp command
>> line you've used?
>> 
>> regards
>> Andrew
>> 
>>        -----Original Message-----
>>        From: Zhonghai Wang [mailto:zhonghaiw at gmail.com]
>>        Sent: Fri 7/14/2006 12:14 AM
>>        To: gdal-dev at lists.maptools.org
>>        Cc:
>>        Subject: [Gdal-dev] need tools for TIF image reprojection
>> 
>> 
>>        Hi guys,
>> 
>>        I need a tool to reproject my TIF images, either free or non-free
>> software.
>>        I've tried with the GDAL utilities, sure I can do the reprojection,
>> but the coordinates seems not correct, there are serveral hundert meters
>> displacement according to the my base maps.
>> 
>>        thanks for your info.
>> 
>>        zhonghai
>> 
>> 
>> 
>> 
>