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<p class="MsoNormal">Hi group,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am having a heck of a time figuring out how to have MapServer ignore NODATA values in a WMS. Please help!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">***THE DATA<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">GDAL shows the NODATA value of this TIFF to be -999:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">C:\WorkSpace\medem2>gdalinfo mosaic100.tif<o:p></o:p></p>
<p class="MsoNormal"> <snip><o:p></o:p></p>
<p class="MsoNormal"> NoData Value=-999<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I also confirmed this in ArcGIS, the NoData pixels do not draw. The raster is a 32-bit float (a DEM).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">***THE MAPFILE<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have tried the following, which the docs all indicate should work:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> PROCESSING "NODATA=-999" (nodata pixels show as black)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> PROCESSING “SCALE=-3,950” (again nodata pixels -999 show as black, it does scale the rest of the data)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> CLASS<o:p></o:p></p>
<p class="MsoNormal"> EXPRESSION ([pixel] > -999) (whole image is white)<o:p></o:p></p>
<p class="MsoNormal"> END<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> PROCESSING "LUT=0:0,100:128,500:192,951:255" (nodata pixels show black, it does apply the LUT correctly otherwise)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">***CHECK IT OUT<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">You can see this for yourself if you like, use this WMS:<o:p></o:p></p>
<p class="MsoNormal"> <a href="http://mapserver.maine.gov/wms/mapserv.exe?map=c:/wms/topos.map&">
http://mapserver.maine.gov/wms/mapserv.exe?map=c:/wms/topos.map&</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Choose the Maine_DEM_2m group<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#1F497D">===============================<br>
<b>Michael Smith MS GISP</b><br>
State GIS Manager, Maine Office of GIS<br>
State of Maine, Office of Information Technology<br>
<i>michael.smith _at_ maine.gov</i> 207-215-5530<br>
<br>
Board Member, Maine GeoLibrary<br>
Education Chair, Maine GIS Users Group<br>
State Rep, National States Geographic Information Council</span><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><br>
</span><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><img border="0" width="299" height="68" id="_x0000_i1025" src="cid:image001.jpg@01CF1E9E.2C978FB0"></span><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><br>
<br>
</span><span style="font-size:8.0pt;color:#1F497D">State House Station 145<br>
51 Commerce Drive<br>
Augusta, ME 04333-0145<br>
69<sup>o</sup> 47' 58.9"W 44<sup>o</sup> 21' 54.8"N</span><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">
</span><o:p></o:p></p>
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