[Gdal-dev] VRT Dataset problem

[Frank Warmerdam]

On 7/6/05, Chris Hodgson <chodgson at refractions.net> wrote:
> I'm trying to write a VRT file which tiles several images together -
> each image is a google maps tile :)
> 
> I think my problem is that I need to define the color table for the
> vrtrasterband since I have defined it as "palette" ColorInterp. However,
> the individual tile images do not have identical color palettes (though
> I suspect they have very nearly the same colors, just at different table
>   indexes). Is there a way, with a vrt file, to tell gdal to map the
> colors from the table into a normal RGB colorspace?

Chris, 

There is no way currently with VRT files to remap pixel values or
to expand paletted images to RGB.   You can convert files into 
RGB with the pct2rgb.py script.  I would suggest doing this, merging
the resulting RGB files, and then using rgb2pct.py to boil them back
down to paletted images (if necessary). 

> Anyways, the sympom is that when I do a galinfo on the vrt file, I get
> a segfault:

It should not be segfaulting.  Can you provide a small test case for this
via bugzilla for me to look into? 

Best regards,
-- 
---------------------------------------+--------------------------------------
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    | Geospatial Programmer for Rent