Bug report #17828
Align Rasters tool does not respect NODATA value.
| Status: | Closed | ||
|---|---|---|---|
| Priority: | Normal | ||
| Assignee: | - | ||
| Category: | Rasters | ||
| Affected QGIS version: | 2.18.15 | Regression?: | No |
| Operating System: | Windows | Easy fix?: | No |
| Pull Request or Patch supplied: | No | Resolution: | end of life |
| Crashes QGIS or corrupts data: | No | Copied to github as #: | 25723 |
Description
If Align Rasters is used on rasters that have a NODATA value set, it does not respect this but treats this as a real numeric value instead.
To reproduce:
- Create two rasters of different resolutions, both having NODATA set to (for example) 99999 and having some regions of missing data Use Align Rasters to resample the lower-res one to match the higher-res, using something other than Nearest Neighbour.
- Note that the output raster does not have a NODATA value set. Additionally it includes, aroud the missing regions, smooth gradients from -99999 to the real values. One could reset the NODATA metadata, but one would be left with these gradients.
So two things to remedy: Firstly that the output file needs to have a NODATA value (presumably user-selectable, to cope with the case where input files have different values), but more importantly that the NODATA values of the input files need to be respected when resampling.
Thank you for considering!
History
#1
Updated by Jürgen Fischer almost 6 years ago
- Status changed from Open to Feedback
Please test with QGIS 3.4 - QGIS 2.18 reached it's end of life.
#2
Updated by Giovanni Manghi over 5 years ago
- Resolution set to end of life
- Status changed from Feedback to Closed
End of life notice: QGIS 2.18 LTR
Source:
http://blog.qgis.org/2019/03/09/end-of-life-notice-qgis-2-18-ltr/
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