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<p class="MsoNormal">Dear all, <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I few times I have posted to the list trying to promote the idea of providing iterators over pixels in a raster band , and more generally to make raster data accessible using (future) standard conforming ranges. It would make implementing
algorithms on raster data a lot more intuitive. These ideas are implemented in Pronto Raster which is an OSGeo Community C++ library. Feedback in this list has been that such a solution would incur costly computational overheads.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I now have some preliminary benchmark results, where I compare Pronto Raster solutions for a simple raster overlay operation (OUT = 3 * A + B * C) to a direct and idiomatic GDAL implementation. The results seem to indicate that overheads
can be negligible, depending on which Pronto Raster functions are used. I would very much appreciate it if some more experienced GDAL C++ users could look at my “idiomatic GDAL implementation” to see if it really is what it claims to be and I am not overstating
the results. I can use your help.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’d also be interested to hear any opinion about these results and the costs / benefits associated with providing pixel ranges for raster bands.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">For details on the benchmark see here: <a href="https://github.com/ahhz/raster/blob/master/docs/_posts/2018-06-14-Preliminary-benchmark-results-are-promising.md">https://github.com/ahhz/raster/blob/master/docs/_posts/2018-06-14-Preliminary-benchmark-results-are-promising.md</a>
<o:p></o:p></p>
<p class="MsoNormal">or here: <a href="http://ahhz.github.io/raster/Preliminary-benchmark-results-are-promising/">
http://ahhz.github.io/raster/Preliminary-benchmark-results-are-promising/</a> <o:p>
</o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Many thanks, Alex<o:p></o:p></p>
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