Bug report #15679
Raster resampling happens before map canvas rotation
| Status: | Closed | ||
|---|---|---|---|
| Priority: | Normal | ||
| Assignee: | - | ||
| Category: | Unknown | ||
| Affected QGIS version: | 2.16.3 | Regression?: | No |
| Operating System: | Easy fix?: | No | |
| Pull Request or Patch supplied: | No | Resolution: | end of life |
| Crashes QGIS or corrupts data: | No | Copied to github as #: | 23602 |
Description
If you use QGIS' canvas rotation feature and have raster images in your map, they will look much worse than intended.
It seems like the resampling is done before the rotation. The rotation of course leads to different neighborhood relationships between pixels so the quality degrades. Would it be possible to resample after rotating?
Attached is an example of the same area with Nearest Neighbor resampling as well as Average with 0° and 10° rotation applied. As you can see, the image quality in the 10° Average image looks not very good.
History
#1
Updated by Giovanni Manghi over 7 years ago
- Easy fix? set to No
- Regression? set to No
#2
Updated by Jürgen Fischer about 7 years ago
- Category set to Unknown
#3
Updated by Johannes Kroeger over 6 years ago
- File no resampling on reprojection.png added
This also affects OTF reprojection as shown in this image. I would update the title if I could.
#4
Updated by Giovanni Manghi over 5 years ago
- Resolution set to end of life
- Status changed from Open 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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