[mapguide-users] Preliminary MrSID and ECW Support

[Frank Warmerdam]

Jason Birch wrote:
> MrSID:
> 
> - 5 images in a single directory
> - two at 1.1GB, one at 1GB, one at 490MB, and one at 330MB.

Jason,

To confirm, this was with a single data connection,is that right?  So
you aren't seeing the problem that Chris is seeing?

Chris, for the record, the provider should support a bunch of files
in a given directory, even a mixture of different formats, and
resolutions.

> Issues:
>  - Was unable to rename the Data Connection.  Kept getting a "resource
> busy" error.  Delete/recreate worked.

I saw a lot of problems like this too on the weekend.  MgServer would
report lots of messages about locked resources or something when I
ran it interactively.

>  - Speed is OK, but not great (4-8 seconds depending on screen size and
> zoom level).  

I was getting good performance with a single mrsid or ecw file (sub-second
redraws).  But generally speaking performance will be negatively impacted
by having to access imagery from several wavelet supported formats.

I believe the provider is doing a single windowed request into the
underlying ecw and mrsid SDKs so I don't think there is much room for
further optimization.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGeo, http://osgeo.org