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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">I was experimenting with GDAL VRT and KernelFilteredSource
</span><a href="https://gdal.org/drivers/raster/vrt.html#kernelfilteredsource"><span lang="EN-US">https://gdal.org/drivers/raster/vrt.html#kernelfilteredsource</span></a><span lang="EN-US">. My aim was to sharpen aeriel photos a bit for helping visual image
interpretation. I was rather satisfied with the following that, I believe, is an unsharp mask filter
<a href="https://en.wikipedia.org/wiki/Kernel_(image_processing)">https://en.wikipedia.org/wiki/Kernel_(image_processing)</a>. Excerpt from my VRT file:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><KernelFilteredSource><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> <SourceFilename relativeToVRT="1">P4433H.tif</SourceFilename><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> <SourceBand>3</SourceBand><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> <Kernel normalized="1"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> <Size>5</Size><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> <Coefs> -0.00390625 -0.015625 -0.0234375 -0.015625 -0.00390625 -0.015625 -0.0625 -0.09375 -0.0625 -0.015625 -0.0234375 -0.09375 1.859375 -0.09375 -0.0234375 -0.015625 -0.0625 -0.09375 -0.0625 -0.015625 -0.00390625
-0.015625 -0.0234375 -0.015625 -0.00390625 </Coefs><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> </Kernel><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I tested the sharpened VRT with QGIS and it works well. Now I wonder if it could be possible to configure Mapserver to have KernelFiltered outputformats driven by GDAL and VRT. Derived bands might be useful as well. Any
thoughts?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">-Jukka Rahkonen-<o:p></o:p></span></p>
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