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<p class="MsoNormal">The underlying network file system is opaque to us and can change on occasion. But recently our team were asked to cull unused files due to inode counts.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We’re excited to explore SOZip on our vector data where random seek is important to us, but we’re waiting for that branch to be merged into master. I don’t trust standard zip libraries to be performant for this usage case but I’m willing
to be shown otherwise.<o:p></o:p></p>
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<p class="MsoNormal">Jesse<o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">gdal-dev <gdal-dev-bounces@lists.osgeo.org> on behalf of Laurențiu Nicola via gdal-dev <gdal-dev@lists.osgeo.org><br>
<b>Reply-To: </b>Laurențiu Nicola <lnicola@dend.ro><br>
<b>Date: </b>Friday, December 8, 2023 at 3:01 PM<br>
<b>To: </b>gdallists <gdal-dev@lists.osgeo.org><br>
<b>Subject: </b>[EXTERNAL] [BULK] Re: [gdal-dev] GTiff bit shuffle compression feature request<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif">On Fri, Dec 8, 2023, at 21:32, Even Rouault wrote:<o:p></o:p></span></p>
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<p>yes, poor wording of mine. I meant that if using PREDICTOR=3, one should compare with FILTER=DELTA. But looking more closely, they are not strictly equivalent. PREDICTOR=3 applies the delta as b[0]-a[0], b[1]-a[1], b[2]-a[2], b[3]-a[3] where a[0...3] and
b[0...3] are seen as the 4 byte representation of the float32, whereas FILTER=DELTA does the difference b_float - a_float as floating point. This isn't the same...<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif"><a href="https://www.blosc.org/posts/bytedelta-enhance-compression-toolset/">https://www.blosc.org/posts/bytedelta-enhance-compression-toolset/</a> seems to be the equivalent.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif">> inode allocation<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif">XFS or ZIP?<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif">> extra step to decompress Zarr out of ZIP<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif">Most libraries should be able to read Zarr directly from a ZIP archive.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
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