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<p>Hi Nicolas,</p>
<p> NXarchive was discussed and accepted by the NIAC a long time ago and hasn't had any significant updates since. I think you might need to talk to the ICAT project to get further detail. Perhaps you could encourage the ICAT project to provide updates for
the NXarchive documentation, if it is warranted/useful. For HDF5 compression, we generally recommend sticking to the compression filters already included in the HDF libraries, like ZLIB.</p>
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<p>Cheers,</p>
<p>Ben<br>
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<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> NeXus <nexus-bounces@shadow.nd.rl.ac.uk> on behalf of Nicolas Soler via NeXus <nexus@shadow.nd.rl.ac.uk><br>
<b>Sent:</b> Monday, 11 April 2022 7:24 PM<br>
<b>To:</b> nexus@nexusformat.org<br>
<b>Cc:</b> Nicolas Soler<br>
<b>Subject:</b> [Nexus] NXarchive / compression standards</font>
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<p>Dear all,</p>
<p>I'm new to this list so I may be inquiring about topics that have been discussed before. But anyway, I have two questions here:</p>
<p>1) I have noticed the presence of NXarchive in the application definitions. Does anybody know more about it beyond the provided description? (This is a definition for data to be archived by ICAT).<br>
</p>
<p>2) What about compression filters applied to the underlying HDF5 files? Is the rule to apply ZLIB by default or were there discussions or recommendation around particular techniques and associated data structures?</p>
<p>Many thanks in advance for your insights!</p>
<p>Nicolas<br>
</p>
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