[gdal-dev] How to make VRT offsite areas white?

[Jukka Rahkonen]

Even Rouault <even.rouault <at> mines-paris.org> writes:

> >
> > Knowing tricks is fun but I could tolerate having some parameter driven way
> > for
> > setting the VRT background colour.
> 
> Actually, I'm just thinking that there's another less convoluted way of doing
> it. Try using "-vrtnodata 255 -hidenodata" as options of gdalbuildvrt. 
(This was
> added in https://trac.osgeo.org/gdal/ticket/3327 )

Yes, -vrtnodata 255 -hidenodata made the desired result too. I had read about
those parameters in the buildvrt usage document but I did not realize I should
use those. Even now when I know how to do the trick I must admit that I still
don't really understand the documentation from this part. For users like me I
suggest to add a one line description into buildvrt usage examples somehow like

"Make a virtual mosaic with blue background colour (RGB: 0 0 255)"
gdalbuildvrt -hidenodata -vrtnodata "0 0 255" doq_index.vrt doq/*.tif

-Jukka Rahkonen-