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Hi Andrea,<br>
<br>
You are right, in the current msautotest suite there are several
tests and examples that are not (yet) standardized. The "problem"
with the current version of WCS is that it follows a core+extensions
approach, which is not a problem by itself, it just makes a useful
implementation quite difficult. To provide features for WCS 2.0 that
are also available for older versions of the standard we simply had
to make educated guesses on what is likely to be standardized in
future extensions. For example the "formats" extension was not
available at all when I implemented it in MapServer, but when the
standard was finished, only small changes had to be applied to be
conformant to the extension.<br>
<br>
In the current documentation you'll find a note [1] for what I just
explained.<br>
<br>
In the specific example of the "crs" parameter in the
"wcs:Dimension" element, I think you have stumbled upon an
inconsitency and the test input/documentation needs to be updated.<br>
<br>
Currently the "scaling" extension for WCS 2.0 is under discussion at
the OGC WCS standards working group, and, once it is standardized,
the "Size" and "Resolution" will likely have to be adjusted. (With
the current state of the document, they will be replaced by the
"scaleFactor", "scaleAxes" and "scaleDomain" parameters). I think
the standard document is not publicly available, only in the OGC
internal system.<br>
<br>
Thank you for the hint of putting the parameters into the
"wcs:Extension" element. This was a recent change in the corrigendum
that may not have been taken into account in the implementation.<br>
<br>
Regards,<br>
Fabian<br>
<br>
<br>
[1] <a
href="http://mapserver.org/ogc/wcs_server.html#to-do-items-and-known-limitations">http://mapserver.org/ogc/wcs_server.html#to-do-items-and-known-limitations</a><br>
<br>
<br>
On 08/17/2012 02:24 PM, Andrea Aime wrote:
<blockquote
cite="mid:CA+nxMTsiXcQfODtWtkGKSQrFiuwSGhEzn0R4sGZyOVXMFthx_g@mail.gmail.com"
type="cite">
<div class="gmail_quote">Hi all,
<div>sorry to intrude on the MapServer dev mailing list, but I'd
have a question that</div>
<div>only the people that implemented the WCS 2.0 support could
answer.</div>
<div><br>
</div>
<div>
I see that the MapServer autotest has requests that comprise
parameters which</div>
<div>are not part of the official specification, which add
support for scaling and reprojection.</div>
<div>For example:</div>
<div><br>
</div>
<div><?xml version="1.0"
encoding="UTF-8"?><wcs:GetCoverage xmlns:wcs="<a
moz-do-not-send="true" href="http://www.opengis.net/wcs/2.0"
target="_blank">http://www.opengis.net/wcs/2.0</a>"
service="WCS"
version="2.0.0"><wcs:Format>image/tiff</wcs:Format><wcs:CoverageID>grey</wcs:CoverageID><wcs:DimensionTrim><wcs:Dimension
crs="<a moz-do-not-send="true"
href="http://www.opengis.net/def/crs/EPSG/0/4326"
target="_blank">http://www.opengis.net/def/crs/EPSG/0/4326</a>">lon</wcs:Dimension><wcs:TrimLow>-121.488</wcs:TrimLow><wcs:TrimHigh>-121.487</wcs:TrimHigh></wcs:DimensionTrim><wcs:DimensionTrim><wcs:Dimension
crs="<a moz-do-not-send="true"
href="http://www.opengis.net/def/crs/EPSG/0/4326"
target="_blank">http://www.opengis.net/def/crs/EPSG/0/4326</a>">lat</wcs:Dimension><wcs:TrimLow>0.000</wcs:TrimLow><wcs:TrimHigh>0.001</wcs:TrimHigh></wcs:DimensionTrim></wcs:GetCoverage></div>
<div><br>
</div>
<div>(the Dimension element does not have a crs attribute in the
official spec).</div>
<div><br>
</div>
<div><?xml version="1.0"
encoding="UTF-8"?><wcs:GetCoverage xmlns:wcs="<a
moz-do-not-send="true" href="http://www.opengis.net/wcs/2.0"
target="_blank">http://www.opengis.net/wcs/2.0</a>"
service="WCS"
version="2.0.0"><wcs:Format>image/tiff</wcs:Format><wcs:CoverageID>grey</wcs:CoverageID><wcs:Size
dimension="x">10</wcs:Size><wcs:Size
dimension="y">20</wcs:Size></wcs:GetCoverage></div>
<div>or </div>
<div><?xml version="1.0"
encoding="UTF-8"?><wcs:GetCoverage xmlns:wcs="<a
moz-do-not-send="true" href="http://www.opengis.net/wcs/2.0"
target="_blank">http://www.opengis.net/wcs/2.0</a>"
service="WCS"
version="2.0.0"><wcs:Format>image/tiff</wcs:Format><wcs:CoverageID>grey</wcs:CoverageID><wcs:Resolution
dimension="x">20</wcs:Resolution><wcs:Resolution
dimension="y">20</wcs:Resolution></wcs:GetCoverage></div>
<div><br>
</div>
<div>(there is no Size and Resolution element in the
specification)</div>
<div><br>
</div>
<div>The WCS 2.0 specification says that the scaling,
interpolation, band subsettting and reprojection should have
been</div>
<div>addressed by application profiles that, to date, have not
been released, but my understanding is that in POST</div>
<div>requests these extra things would have to be added inside
the wcs:Extension element.</div>
<div>
<br>
</div>
<div>I also see there is a KVP syntax for them in MapServer.</div>
<div><br>
</div>
<div>Long story short, I'm wondering, where is the above coming
from? Is it educated guesses from the MapServer</div>
<div>developers, or coming from documents that OGC never
released (or that yours truly simply did not find?).</div>
<div>I also looked in other software (Rasdaman) and there is
apparently no trace of handling these extra parameters</div>
<div><br>
</div>
<div>Cheers</div>
<span class="HOEnZb"><font color="#888888">
<div>Andrea</div>
</font></span></div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
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</blockquote>
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