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<div class="moz-cite-prefix">Hello<br>
<br>
Le 17/05/15 06:44, Yuta Sato a écrit :<br>
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cite="mid:CAPqnkJTAqeYroew0Us5SH_Xq9EBNEis3LAwQJ5jJJEq2R-7xVw@mail.gmail.com"
type="cite">
<div dir="ltr">Do you have any idea on which is more precise:
gdalwarp or MRT? Or there is any way in gdalwarp to get the same
image as MRT gives?</div>
</blockquote>
<br>
I do not know for this case. But generally speaking I think that the
question of projection library accuracy is not yet solved. The <i>Geospatial
Integrity of Geoscience Software</i> (GIGS) test suite is one
attempt to answer that kind of question, but it is not yet widely
implemented as far as I know. We have a partial implementation in
GeoAPI [2] and we tried those tests on Proj.4 through JNI bindings.
I found a large difference between Proj.4 and GIGS for "Lambert
Conformal (Belgium)" projection, but I'm not sure that I didn't made
any mistake with Proj.4 parameters.<br>
<br>
More recently I found an other difference between Proj.4 and Circés
(the official software from French mapping agency for coordinate
transformations in France) for the transformation from "Nouvelle
Triangulation Française" (EPSG:4275) to WGS 84 (EPSG:4326). I got
datum shift in opposite directions, but again I'm not sure that I
did no mistake.<br>
<br>
I feel that for answering your question with more confidence, we
would need to push forward the GIGS test effort or something
equivalent. This is a little bit different than the tests provided
by the projects themselves, which sometime tend to be
anti-regression tests rather than test for correctness.<br>
<br>
Martin<br>
<br>
<br>
[1] <a class="moz-txt-link-freetext" href="http://www.iogp.org/geomatics#2521115-gigs">http://www.iogp.org/geomatics#2521115-gigs</a><br>
[2] <a class="moz-txt-link-freetext" href="http://www.geoapi.org/geoapi-conformance/index.html">http://www.geoapi.org/geoapi-conformance/index.html</a><br>
<br>
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