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<p class="MsoNormal"><span style="font-size:11.0pt">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> We are working on use cases where we have to perform operations similar to gdal_translate / gdalwarp on complex valued datasets.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">The last discussion that I could on this topic in the mailing archives is from 2010:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><a href="https://lists.osgeo.org/pipermail/gdal-dev/2010-September/025906.html">https://lists.osgeo.org/pipermail/gdal-dev/2010-September/025906.html</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I’m willing to put in some effort to update the algorithms to handle nodata values for complex valued datasets properly (which it currently appears to ignore). Any pointers on where to start looking or focus
on would help?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">We would like to avoid using pixel functions and manipulating the real/imag parts independently and then putting them back together.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">There are also different options for interpreting nodata. I believe we are limited to real values for this metadata field and adding new fields / changing the type could be pretty disruptive.<o:p></o:p></span></p>
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<li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo1"><span style="font-size:11.0pt">Compare real value only (seems easiest to implement)<o:p></o:p></span></li><li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo1"><span style="font-size:11.0pt">Compare that both real and imaginary values are set to no data (probably better way of checking?)<o:p></o:p></span></li></ol>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">If one were to implement nodata support for complex-valued datasets, which implementation would be preferred.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Thanks<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Piyush<o:p></o:p></span></p>
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