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<div>Do you have any idea why the differences exist? Is it worth
investigating?</div>
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<p>Quite likely subtle differences in behavior of the JPEG
compression library. Mine on ubuntu 20.04 is libjpeg-turbo 2.0.3
with IJG libjpeg 8 ABI. I presume if you built if from source and
linked it against GDAL, you'd get the same checksums.</p>
<p>We should try to minimize tests using JPEG for that reason, but
in that instance, this test is really meant to check JPEG specific
code paths in the COG driver. Or use some kind of perceptualdiff
test for such test, but the "perceptualdiff" utility does consider
"your" and "mine" image to be different, so that wouldn't help.
We'd probably need something clever that tolerates pixel values
differences that can be quite important (the max here is a
difference of 19 units) but detects there's no spatial shift.<br>
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<div dir="ltr" class="gmail_attr">On Wed, Apr 28, 2021 at 8:35
AM Even Rouault <<a
href="mailto:even.rouault@spatialys.com"
moz-do-not-send="true">even.rouault@spatialys.com</a>>
wrote:<br>
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<p>Andew,</p>
<p>visually the difference between your image and the one
generated on my PC are almost indistinguishable (no
spatial shift at least). Please submit a PR adding your
checksums as alternate accepted ones. You may just
remove the "if sys.platform == 'darwin'" case. Hopefully
adding your checksums should fix the OSX CI too</p>
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-- <br>
<div dir="ltr" class="gmail_signature">Andrew Bell<br>
<a href="mailto:andrew.bell.ia@gmail.com" target="_blank"
moz-do-not-send="true">andrew.bell.ia@gmail.com</a></div>
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<pre class="moz-signature" cols="72">--
<a class="moz-txt-link-freetext" href="http://www.spatialys.com">http://www.spatialys.com</a>
My software is free, but my time generally not.</pre>
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