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<p class="MsoNormal"><span style="font-family:"Courier New"">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New"">See this and find test data and example commands
</span><span style="font-family:"Courier New""><a href="https://github.com/opengeospatial/OGC-API-Sprint-August-2020/issues/18"><span lang="EN-US">https://github.com/opengeospatial/OGC-API-Sprint-August-2020/issues/18</span></a></span><span lang="EN-US" style="font-family:"Courier New"">.<br>
<br>
If PixelIsPoint image has these GeoTIFF tags<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><br>
</span><span lang="EN-US" style="font-family:"Courier New"">Geotiff_Information:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> Version: 1<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> Key_Revision: 1.0<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> Tagged_Information:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> ModelTiepointTag (8,3):<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> 0 0 0<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> -90 90 0<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> 1024 0 0<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> 0 90 0<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> 0 1024 0<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> -90 0 0<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> 1024 1024 0<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> 0 0 0<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> End_Of_Tags.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> Keyed_Information:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> GTModelTypeGeoKey (Short,1): ModelTypeGeographic<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""> GTRasterTypeGeoKey (Short,1): RasterPixelIsPoint<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New"">and PixelIsArea has the same tags except GTRasterTypeGeoKey (Short,1): RasterPixelIsArea<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New"">Now shouldn’t the PixelIsPoint image slide half a pixel to the left and upwards compared to PixelIsArea image? If I run these images through gdalwarp the warped pixel_is_area image shows
corner coordinates Upper Left (-180.0000000, 90.0000000) and pixel_is_point image Upper Left (-179.9560547, 89.9560547), so sliding happens to the right and downwards.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New"">It is late and I feel fuzzy but shouldn’t the pixel_is_point variant has smaller easting, greater northing instead, thus (-180,0439453, 90,04394531)?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New"">The images are georeferenced with tiepoints/GCPs, perhaps it adds something to the soup?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New"">-Jukka Rahkonen-<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Courier New""><o:p> </o:p></span></p>
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