[Xastir] MrSid format DRG maps

[Curt, WE7U]

On Tue, 10 Oct 2006, Derrick J Brashear wrote:

> GDAL might be able to link against a MrSID SDK, which would mean it would
> come along for free with GDAL raster support, but I'd still like to find a
> free format with good compression to use instead.

As a matter of fact you can do the MrSID stuff with GDAL.  I'm on
the GDAL mailing list and I think you might be too Derrick.

Of course we don't have raster support done yet in Xastir for GDAL,
only support for some of the vector formats (using the OGR library).


> DjVu is probably it,

I don't know that one.


> > Some states have started making MrSID topo maps or perhaps DOQQ
> > images available for free.  Sometimes these are cropped USGS images
> > (no white border) as well.  Disks are cheap these days and I'd much
> > rather see them make the original unmodified files available for
> > download.
>
> PA has unmodified DOQQs online (geotiff, bil or bsq) and they are
> collarless, but i can find no evidence they're cropped.

I'm not as familiar with DOQQ's as I am the DRG's.  I know we've had
problems with users trying to use the cropped or MrSID-encrypted
DRG's.

I've personally downloaded DOQQ's from the local University library
download site and used them in Xastir.  They had to be tweaked first
because they were created using ESRI software and so were missing
proper geoTIFF headers, but that was easily solved with Tom's help.

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