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<P><FONT SIZE=2 FACE="Arial">Hi,</FONT>
<BR><FONT SIZE=2 FACE="Arial">This is mostly directed at Frank and other FDO folks. I am needing to implement MGOS for a client using some publicly available aerial photos which we plan to expose via base layers and then pre-render via a tile rendering script. In this case, there are approximately 1300 MrSID images that make up a County worth of data. The maximum image size is 3 MB. When defining a data connection using the GDAL FDO provider that points to this folder, I do not have favorable results. I can repeatedly get MapGuide Server to crash while this layer is rendered and the crashes occur during the GDAL reads of the images, but never while reading the same image and never with very meaningful debug information. This is using MGOS 1.1.0 and FDO 3.1 since 1.2.0 beta 1 currently does not work with the single threaded GDAL provider. Along those lines, it's a shame to see a quad processor server utilizing only 25% of its potential horsepower because of single threading….</FONT></P>
<P><FONT SIZE=2 FACE="Arial">While watching what is happening while running MapGuide Server in interactive and debug mode, it is apparent that the GDAL provider tries to open every image in the data connection folder for each map render. This happens even if the current view is zoomed to a level where only 4 images need to be opened. This is obviously very inefficient and probably part of the crashing problem. A solution to this would be to use an image tile catalog index so that only the images needed for the view are accessed.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">I see that there was some talk on this subject, mostly in the FDO mailing list, back in January. But, has this moved forward at all and can we expect to see image catalogs supported by they GDAL provider in the near future? If so, when?</FONT></P>
<P><FONT SIZE=2 FACE="Arial">By the way, I started using FWTools to attempt to mosaic these images, but quickly discovered that a resultant Erdas image would have been in the 200 GB range.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">Thanks for any insight into these matters.</FONT>
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<P><FONT SIZE=1 FACE="Tahoma">Andy Morsell, P.E.</FONT>
<BR><FONT SIZE=1 FACE="Tahoma">Spatial Integrators, Inc.</FONT>
<BR><A HREF="http://www.SpatialGIS.com"><U><FONT COLOR="#0000FF" SIZE=1 FACE="Tahoma">http://www.SpatialGIS.com</FONT></U></A>
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