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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Alex Highviz <alexhighviz@hotmail.com><br>
<b>Sent:</b> 22 June 2018 18:27:14<br>
<b>To:</b> even.rouault@spatialys.com<br>
<b>Subject:</b> Re: [gdal-dev] Help with idiomatic GDAL solution for raster algebra benchmark</font>
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<br>
On 14/06/2018 21:22, Even Rouault wrote:<br>
><br>
> [ ]<br>
> - 1000x1000 is somewhat small. Perhaps benchmark on larger rasters<br>
><br>
> [ ]<br>
> - it would be interested if you could also benchmark a VRT with Python numpy-<br>
> based pixel function, and enable Numba. See<br>
> <a href="http://www.gdal.org/gdal_vrttut.html#gdal_vrttut_derived_python">http://www.gdal.org/gdal_vrttut.html#gdal_vrttut_derived_python</a> (or just pure<br>
> numpy based computation + Numba)<br>
><br>
> [ ]<br>
> Even<br>
><br>
Hi Even,<br>
<br>
I tried a few of your suggestions and am pleasantly surprised. These <br>
results are for 10000 x 10000 matrices<br>
<br>
VRT with C++ function : 10.1 seconds<br>
<br>
VRT with NUMPY function (no Numba): 9.2 seconds<br>
<br>
GDAL Direct using GetLockedBlockRef: 8.7 seconds<br>
<br>
GDAL Direct using RasterIO: 30.7 seconds<br>
<br>
Pronto Raster: 10.8 seconds<br>
<br>
Just FYI<br>
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