[Qgis-user] gdalbuildvrt crashes with large number of images (Was: How do you deal with lots of raster data?)

[Alister Hood]

Ah, no.
Now I remember VRT is not the answer anyway; someone asking essentially the same question was complaining a while back that a VRT is very slow to load or pan, and rasterlite was suggested as the solution. 
 

-----Original Message-----
From: Alister Hood 
Sent: Thursday, 2 September 2010 1:13 p.m.
To: qgis-user at lists.osgeo.org
Subject: RE: [Qgis-user] gdalbuildvrt crashes with large number of images (Was: How do you deal with lots of raster data?)

Thanks,
I probably should have figured out that vrt is what I was after.
Now I have a problem:
I can create a vrt with only a small number of images using QGIS from the standalone 1.5.0 Windows installer (QGIS from the osgeo installer refuses to accept .ecw images).  But if I try to create one with all the files I get this crash fairly quickly:

gdalbuildvrt.exe - Application Error

The instruction at "0x7c9369da" referenced memory at "0x0000000". The memory could not be "read".
 
Has anyone else experienced a similar problem?


-----Original Message-----
From: maning sambale [mailto:emmanuel.sambale at gmail.com] 
Sent: Wednesday, 1 September 2010 9:01 p.m.
To: Alister Hood
Cc: qgis-user at lists.osgeo.org
Subject: Re: [Qgis-user] How do you deal with lots of raster data?

two options:

- gdal's Virtual Raster Format (vrt) - you can create vrt files using
the Raster Tools plugin
- RasterLite - looks promising but not using it at the moment

On Wed, Sep 1, 2010 at 4:44 PM, Alister Hood <alister.hood at synergine.com> wrote:
> Hi everyone,
> I'm looking for insight into dealing with large amounts of raster data in
> QGIS; at the moment I'm really interested in just displaying background
> images, not doing raster analysis.
>
> Trying to add several hundred ecw images takes an extremely long time and a
> lot of memory.  I thought QGIS might establish the location of each image
> but only load images that are visible in the map extents (and maybe adjacent
> images, to speed up panning and zooming).  However it seems like it must be
> loading all of the images.  Is that right?
>
> Would it be better for me to install some sort of tile server that I can
> load the images into and connect QGIS to?  How do other people deal with
> large amounts of raster data?
>
> Thanks,
> Alister
>
> _______________________________________________
> Qgis-user mailing list
> Qgis-user at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/qgis-user
>
>



-- 
cheers,
maning
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