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<p class="MsoNormal"><a name="_GoBack"></a><span lang="EN-US">Hello,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I am using GDAL through OTB (the Orfeo Toolbox) to process TSX/TDX products with the specific driver: COSAR/COSAR Annotated Binary Matrix (TerraSAR-X).<o:p></o:p></span></p>
<p class="MsoNormal" style="text-align:justify"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span lang="EN-US">With TSX products, the driver works fine.
<o:p></o:p></span></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span lang="EN-US">I have also tried to read CoSAR files from TDX products. Data have a huge difference with a floating point data format instead of integer values. This floating format is
a specific format called "Half Precision Floating Point" for each of the complex values. Thus, TDX products are not well-interpreted. Further information are available in TD-GS-PS-3028_TanDEM-X-Experimental-Product-Description_1.2. The annotations seem to
be the same than TSX products. <o:p></o:p></span></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span lang="EN-US">I need your help to include this new format in GDAL and so in OTB.<o:p></o:p></span></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span lang="EN-US">As far as I can understand, the specific driver for CoSAR binaries is implemented in
<a href="https://github.com/OSGeo/gdal/blob/master/gdal/frmts/cosar/cosar_dataset.cpp" target="_blank">
https://github.com/OSGeo/gdal/blob/master/gdal/frmts/cosar/cosar_dataset.cpp</a>. The data type is set to GDT_CInt16. I think that explains why TDX are not well-interpreted. In my opinion, in order to include TDX products a conversion has to be made before
assigning the buffer. I have found an algorithm to convert “half float” to single float :
<a href="http://blog.schmorp.de/data/binary16/fasthalffloatconversion.pdf">http://blog.schmorp.de/data/binary16/fasthalffloatconversion.pdf</a>
<o:p></o:p></span></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span lang="EN-US">Do you think, is it possible to implement this feature in GDAL?<o:p></o:p></span></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span lang="EN-US">Regards,<o:p></o:p></span></p>
<p class="MsoNormal" style="text-align:justify;text-autospace:none"><span lang="EN-US">Gaëlle.</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#DEEAF6;mso-fareast-language:FR">--------------------------------------------------------------------------------------------------------------<o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="color:#1F4E79;mso-fareast-language:FR">Gaëlle Usseglio</span></b><span style="color:#1F4E79;mso-fareast-language:FR"> -</span><i><span style="color:#5B9BD5;mso-fareast-language:FR">Thales Services</span></i><span style="color:#5B9BD5;mso-fareast-language:FR"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#5B9BD5;mso-fareast-language:FR">Responsable de prestation :
</span><span style="color:#1F4E79;mso-fareast-language:FR">Support HPC</span><span style="color:#5B9BD5;mso-fareast-language:FR"> (Portages, Optimisations, Audits, Expertises, etc.)<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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