[gdal-dev] GML lat-lon coverages and interoperability

Andrea Aime andrea.aime at geo-solutions.it
Mon Apr 3 05:58:01 PDT 2017

On Mon, Apr 3, 2017 at 2:32 PM, Rahkonen Jukka (MML) <
jukka.rahkonen at maanmittauslaitos.fi> wrote:

> With orthophoto coverages I believe that all cases could be handled with
> the default gridFunctions: startPoint at gml:Low, axisOrder +1 +2, sequence
> rule “Linear”. As far as I have understood GDAL trusts that this is also
> what the other partners do. However, it seems that GeoServer developers
> have decided to handle the latitude-longitude axis flip in WCS 2.0.1 by
> changing the order of grid axis with a function instead of writing the
> offsetVectors to suit with the default +1 +2 axis order.
> <gml:coverageFunction>
> <gml:GridFunction>
> <gml:sequenceRule axisOrder="+2 +1">Linear</gml:sequenceRule>
> <gml:startPoint>0 0</gml:startPoint>
> </gml:GridFunction>
> </gml:coverageFunction>

Hi Jukka,
the decision was not arbitrary, and imho, necessary.

Rasters pixels are normally represented as east/north, but OGC forces us to
describe geographic data in lat/lon order.
So how do you tell the client, "look, I'm telling you that the axis order
is north/east, but really, I'm giving you back data in east/north order


GeoServer Professional Services from the experts! Visit
http://goo.gl/it488V for more information.

Ing. Andrea Aime
Technical Lead

GeoSolutions S.A.S.
Via di Montramito 3/A
55054  Massarosa (LU)
phone: +39 0584 962313
fax: +39 0584 1660272
mob: +39  339 8844549



Le informazioni contenute in questo messaggio di posta elettronica e/o
nel/i file/s allegato/i sono da considerarsi strettamente riservate. Il
loro utilizzo è consentito esclusivamente al destinatario del messaggio,
per le finalità indicate nel messaggio stesso. Qualora riceviate questo
messaggio senza esserne il destinatario, Vi preghiamo cortesemente di
darcene notizia via e-mail e di procedere alla distruzione del messaggio
stesso, cancellandolo dal Vostro sistema. Conservare il messaggio stesso,
divulgarlo anche in parte, distribuirlo ad altri soggetti, copiarlo, od
utilizzarlo per finalità diverse, costituisce comportamento contrario ai
principi dettati dal D.Lgs. 196/2003.

The information in this message and/or attachments, is intended solely for
the attention and use of the named addressee(s) and may be confidential or
proprietary in nature or covered by the provisions of privacy act
(Legislative Decree June, 30 2003, no.196 - Italy's New Data Protection
Code).Any use not in accord with its purpose, any disclosure, reproduction,
copying, distribution, or either dissemination, either whole or partial, is
strictly forbidden except previous formal approval of the named
addressee(s). If you are not the intended recipient, please contact
immediately the sender by telephone, fax or e-mail and delete the
information in this message that has been received in error. The sender
does not give any warranty or accept liability as the content, accuracy or
completeness of sent messages and accepts no responsibility  for changes
made after they were sent or for other risks which arise as a result of
e-mail transmission, viruses, etc.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/gdal-dev/attachments/20170403/924f3eb9/attachment.html>

More information about the gdal-dev mailing list