Specific MrSid images not displaying.

[andrewd]

I will attach the MrSid file that's causing the problem (I have lots of these, this is just one). Other rasters are working for me. And this MrSid worked in MGOS1.0.2...Because of this, I'm starting 2 tickets - one here, and one on the FDO site (since it could be either one causing the problem). I've been in touch with Jason Birch about this, and he has the same problem with this file as I do.

See also: ​http://trac.osgeo.org/fdo/ticket/308

[TomFukushima]

Hi Andrew, are some MrSID files working for you or are they all failing? Tom

[andrewd]

None of my MrSid's are working - but they all come from the same place, so that's not as telling as it seems. Like I said in the ticket though, Jason Birch tested out my MrSid and had the same problem as me - and he can see other MrSid's.

[jbirch]

Added link to FDO ticket.

In my testing, it looks as if the MrSID is being parsed properly by the GDAL provider (CPL_DEBUG shows it reading the various levels), but I end up with a white image on my screen.

Using the current version of OpenEV distributed with FWTools, I can see the image just fine.

My understanding is that this image is in CANST-NB83-CSRS which I believe is the same as:

​http://spatialreference.org/ref/epsg/2953/ogcwkt/

I tried setting appropriate map extents and referencing the image from the map (to see if it was not showing just because of the extents) but was not successful with this.

[jbirch]

Virtual raster

[jbirch]

This image works in 2.1, with a little bit of finesse.

The easiest way of dealing with it is to use gdalbuildvrt to create a virtual data set for the image, and then insert the appropriate SRS element. See attached.

The more traditional MapGuide way of dealing with it is to set a CS override on the FeatureSource, set the same projection on the Map, and then set the bounds of the map explicitly. See the attached MGP which assumes the image is saved at C:\