[Geoserver-devel] Returned envelope not matching requested BBox in WCS

Hi again,

yet more tales of woe from me. I'm trying to request identical sections of two coverages for which the source data does not have identical metrics (same CRSs, but different envelopes and resolutions). I'm trying to feed them into a WPS to do some coverage maths, so the pixels should line up exactly, testing for which is included in the input-checking in the WPS.

The problem is that when I make requests for the two coverages with identical request BBOX parameters, the returned coverages don't have matching envelopes.

In both cases I'm requesting a BBOX 4428336.328601,5800831.4255006,4428986.328601,5801316.4255006
with width 130 and height 97

but the results I'm getting are
Env[4428336.328600899 : 4428985.858207594, 5800831.4255015 : 5801314.946300528]
and
Env[4428336.328600899 : 4428985.328600899, 5800831.4255015 : 5801314.9255015]

a few decimal points / millimetres difference I could live with, particularly if it was consistent, but these are relatively fairly big differences coming out, and different depending on the source coverage (which of course as a WCS client I can't see). The source and request CRSs are identical btw, so it's not directly a CRS transformation problem.

If having some sample data for testing would help then let me know and I can send some.

Cheers,

Edward Nash

--
preagro TP7 - Geodateninfrastruktur
http://www.preagro.de

Universität Rostock
Agrar- und Umweltwissenschaftliche Fakultät
Professur für Geodäsie und Geoinformatik
Justus-von-Liebig-Weg 6
18059 Rostock

Tel: +49 381 498 2164
Fax: +49 381 498 2188
Web: http://www.auf.uni-rostok.de/gg

Hi Edward,

can you send me some sample data? I would like to test this issue and see where is the problem.

Thanks,
Alessio.

On 2/5/07, Edward Nash <edward.nash@anonymised.com700…> wrote:

Hi again,

yet more tales of woe from me. I’m trying to request identical sections
of two coverages for which the source data does not have identical
metrics (same CRSs, but different envelopes and resolutions). I’m trying
to feed them into a WPS to do some coverage maths, so the pixels should
line up exactly, testing for which is included in the input-checking in
the WPS.

The problem is that when I make requests for the two coverages with
identical request BBOX parameters, the returned coverages don’t have
matching envelopes.

In both cases I’m requesting a BBOX
4428336.328601,5800831.4255006,4428986.328601,5801316.4255006
with width 130 and height 97

but the results I’m getting are
Env[4428336.328600899 : 4428985.858207594, 5800831.4255015 :
5801314.946300528 ]
and
Env[4428336.328600899 : 4428985.328600899, 5800831.4255015 :
5801314.9255015]

a few decimal points / millimetres difference I could live with,
particularly if it was consistent, but these are relatively fairly big
differences coming out, and different depending on the source coverage
(which of course as a WCS client I can’t see). The source and request
CRSs are identical btw, so it’s not directly a CRS transformation problem.

If having some sample data for testing would help then let me know and I
can send some.

Cheers,

Edward Nash


preagro TP7 - Geodateninfrastruktur
http://www.preagro.de

Universität Rostock
Agrar- und Umweltwissenschaftliche Fakultät
Professur für Geodäsie und Geoinformatik
Justus-von-Liebig-Weg 6
18059 Rostock

Tel: +49 381 498 2164
Fax: +49 381 498 2188
Web: http://www.auf.uni-rostok.de/gg


Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier.
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642


Geoserver-devel mailing list
Geoserver-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-devel

Eng. Alessio Fabiani
Vice President/CTO GeoSolutions

http://www.geo-solutions.it


Hi Edward,
I have corrected the problem … there was something wrong when resampling the coverage.
Now the resulting envelopes are correct. I have attached the two GeoTIFFs generated by your sample data.

The changes have been committed on SVN GeoServer 1.5.x and trunk. They will be included in the next GeoServer release, which is very soon, I think the end of this week or at least the beginning of the next.

On 2/5/07, Edward Nash <edward.nash@anonymised.com700…> wrote:

Hi again,

yet more tales of woe from me. I’m trying to request identical sections
of two coverages for which the source data does not have identical
metrics (same CRSs, but different envelopes and resolutions). I’m trying
to feed them into a WPS to do some coverage maths, so the pixels should
line up exactly, testing for which is included in the input-checking in
the WPS.

The problem is that when I make requests for the two coverages with
identical request BBOX parameters, the returned coverages don’t have
matching envelopes.

In both cases I’m requesting a BBOX
4428336.328601,5800831.4255006,4428986.328601,5801316.4255006
with width 130 and height 97

but the results I’m getting are
Env[4428336.328600899 : 4428985.858207594, 5800831.4255015 :
5801314.946300528 ]
and
Env[4428336.328600899 : 4428985.328600899, 5800831.4255015 :
5801314.9255015]

a few decimal points / millimetres difference I could live with,
particularly if it was consistent, but these are relatively fairly big
differences coming out, and different depending on the source coverage
(which of course as a WCS client I can’t see). The source and request
CRSs are identical btw, so it’s not directly a CRS transformation problem.

If having some sample data for testing would help then let me know and I
can send some.

Cheers,

Edward Nash


preagro TP7 - Geodateninfrastruktur
http://www.preagro.de

Universität Rostock
Agrar- und Umweltwissenschaftliche Fakultät
Professur für Geodäsie und Geoinformatik
Justus-von-Liebig-Weg 6
18059 Rostock

Tel: +49 381 498 2164
Fax: +49 381 498 2188
Web: http://www.auf.uni-rostok.de/gg


Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier.
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642


Geoserver-devel mailing list
Geoserver-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-devel

Eng. Alessio Fabiani
Vice President/CTO GeoSolutions

http://www.geo-solutions.it


(attachments)

2001.tiff (46.4 KB)
kamp_umriss.tiff (2.61 KB)