[GRASSLIST:2637] Re: Can I import USGS DOQQ files?

[Eric G. Miller]

On Wed, 07 Nov 2001 18:26:22 -0500, Kevin Slover <kjslover at nhc.noaa.gov> wrote:

> Ben,
> 	looking at the DOQQ's that you are able to download from datadepot.com,
> they come in TIF format.  I have been able to import these using
> r.in.tiff without too many issues.  
> You are exactly correct in saying that they are essentially big infrared
> photographs with 1 meter resolution.  They are also generally
> georeferenced...you are lucky that the file size is only 7MB...generally
> TIF formats for DOQQ are much larger from what I have seen, and
> generally they will then compress them using MrSID, which at this time,
> is not supported within GRASS.  And MrSID (Lizardtech) does not have a
> conversion at this point from SID to TIF...

I suspect either you downloaded a MrSID file (which GRASS cannot support)
or your download failed to complete. Seven megabytes is way too small
for any DOQQ I've ever seen.  B&W run near 50MB, while color/CIR ones
run at about 150MB each!  It takes four DOQQ's to make just one 7.5
minute quadrangle.  So I hope you have bandwidth and disk space...

-- 
Eric G. Miller <egm2 at jps.net>