[GRASSLIST:2034] Re: GRASS and USGS images on terraserver.microsoft.com

[Markus Neteler]

On Thu, Jun 28, 2001 at 09:17:40AM -0400, Frank Warmerdam wrote:
> Nathaniel Pendleton wrote:
> > 
> > Can these image and the "world file" work easily with GRASS?
> > 
> > USGS black and white images in
> > 1, 2, 4, 8, 16, 32, 64, and 128 meter resolution JPGs
> > AND
> > "world file" for GIS are available for FREE at
> > http://terraserver.microsoft.com
> > 
> > find the image desired, and click on USGS logo (top right)
> > then down load the image and the save the worldfile as a ".jpgw"
> > 
> > data could would be something like this.
> > [start snip]
> > 16.000000
> > 0.000000
> > 0.000000
> > -16.000000
> > 313600.000000
> > 4307200.000000
> > [close snip]
> > 
> > Can these image and the "world file" work easily with GRASS?
> 
> Nathaniel,
> 
> In GRASS 5 you can use r.in.gdal to import JPEG files if you have GDAL support
> with your GRASS.  However, changes to GDAL to support world files was only 
> added in May, so you would need a GDAL built from CVS, since that feature was
> not in GDAL 1.1.4. 
> 
> You could also use older GDAL builds and fix the georeferencing yourself after
> import, or use some external utility (such as gdal_translate) to convert the
> JPEG to TIFF format, and then r.in.gdal will honour the world file.  
> 
> Note that the world file should have the extension .jgw to use with r.in.gdal
> for JPEG files.  It should have the extension .tfw to use with TIFF files.

A small addition:

The r.in.tiff also supports .tfw files from GRASS 5beta11 onwards.

Kind regards

 Markus Neteler