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Hi Henry, <br>
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You could try: <a href="https://grass.osgeo.org/grass76/manuals/addons/r.patch.smooth.html">
https://grass.osgeo.org/grass76/manuals/addons/r.patch.smooth.html</a><br>
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Cheers, <br>
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Stefan <br>
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<div id="x_divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> grass-user <grass-user-bounces@lists.osgeo.org> on behalf of Henry House <hajhouse@houseag.com><br>
<b>Sent:</b> Thursday, October 17, 2019 8:40:42 PM<br>
<b>To:</b> grass-user@lists.osgeo.org <grass-user@lists.osgeo.org><br>
<b>Subject:</b> [GRASS-user] stitching together aerial imagery with edge blending</font>
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<div class="PlainText">I have a selection of vintage aerial imagery from 1929 which features<br>
variable brightness, with edges of images generally overly dark. While<br>
I'm grateful that imagery from 1929 exists at all for my study area,<br>
this is annoying and detrimental to classification efforts. As most of<br>
the images overlap each other around their edges, I'd like to blend the<br>
pixels from area where the raster overlap in some way, ideally such that<br>
there are no sharp changes visible in transition from one exposure to<br>
another in the patched map.<br>
<br>
I can patch the images together with r.patch, but then I get the<br>
artifacts of the edges. I also thought using r.mapcalc to blend pixels<br>
pixels 50/50 where maps overlap. But surely this has been done many<br>
times before and I can avoid inventing my own method. Do there exist any<br>
specialized tools for smart stitching of aerial imagery tiles together<br>
such that overlapping area a blended; or could someone suggest a good<br>
technique?<br>
<br>
--<br>
Henry House<br>
House Agricultural Consultants<br>
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