[GRASS-user] r.texture NULL value error

[Markus Neteler]

On Mon, Nov 24, 2008 at 2:39 PM, Hufkens Koen <koen.hufkens at ua.ac.be> wrote:
> Hi list,
>
> I've been trying to run a r.texture filter on a map but I constantly get the
> error:
>
> ERROR: Negative or no data pixel found. This module is not yet able to
>        process no data holes in a map, please fill with r.fillnulls or
>        other algorithms
>

I ran into this myself a few minutes ago :)
The trick is that *all* pixels in the current region are need to be
set to non-NULL.
If NULL pixels are present, r.texture fails.

run
r.univar mapname
to see how many NULL cells are in the current region.

Solution:
- either zoom into area without NULL pixels (won't always make sense)
- or fill the NULL areas with some value (various options)
- (or fix r.texture if possible).

Markus