<div dir="ltr"><div>What I did is using int16. The max error is 1.2 mm (if I did the maths correctly). The size with that change is about 24 MB</div><div>If anybody wants even more accuracy, they can use int32. The reduction is smaller, but still less than 100 MB.</div><div>(any benefit between uint16 vs int16? the positive and negative ranges are almost the same, so I do not need offset with int16)</div><div><br></div><div>I was just telling it to take into consideration when those files become official.</div></div><br><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Sun, 27 Apr 2025 at 14:43, Even Rouault <<a href="mailto:even.rouault@spatialys.com">even.rouault@spatialys.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><u></u>
<div>
<p><br>
</p>
<div>Le 24/04/2025 à 21:51, Mike Taves via
PROJ a écrit :<br>
</div>
<blockquote type="cite">
<p dir="ltr">There is Git Large File Storage (Git LFS), which has
a limit of 2GB.</p>
</blockquote>
<p>Yes, but there are billing / bandwidth implications. I remember
we had it enabled, but CI cloning typically exhausted the allowed
free bandwidth.</p>
<p>Javier, maybe you can try using gdal_translate -scale X X X X -ot
UInt16 -co COMPRESS=DEFLATE -co TILED=YES -co PREDICTOR=2 with the
appropriate scaling values ?</p>
<p>Or gdal_translate -co DISCARD_LSB=X -co COMPRESS=DEFLATE -co
TILED=YES -co PREDICTOR=3 to nullify least signifcant bits of the
mantissa.<br>
</p>
<p><br>
</p>
<blockquote type="cite">
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Fri, 25 Apr 2025, 04:37
Javier Jimenez Shaw via PROJ, <<a href="mailto:proj@lists.osgeo.org" target="_blank">proj@lists.osgeo.org</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div dir="ltr">
<div>Hi</div>
<div><br>
</div>
<div>I am playing with the new American geoid model
SGEOID2022</div>
<div><br>
</div>
<div>After compressing with this command (can I do it
better?)</div>
<div><span style="font-family:monospace">gdal_translate
sgeoid2022.tif sgcomp.tif -co COMPRESS=DEFLATE -co
TILED=YES -co PREDICTOR=3</span></div>
<div>I get a 110 MB file (and it is only one band. No
velocities).</div>
<div><br>
</div>
<div>GitHub has a limit of 100MB:</div>
<div><a href="https://docs.github.com/en/repositories/working-with-files/managing-large-files/about-large-files-on-github" rel="noreferrer" target="_blank">https://docs.github.com/en/repositories/working-with-files/managing-large-files/about-large-files-on-github</a></div>
<div><br>
</div>
<div>Just to let you know.</div>
<div><br>
</div>
<div>Cheers,</div>
<div>Javier.</div>
</div>
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</blockquote>
</div>
<br>
<fieldset></fieldset>
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</blockquote>
<pre cols="72">--
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My software is free, but my time generally not.</pre>
</div>
</blockquote></div>