Feature request #10886
relative color tables for raster data
| Status: | Open | ||
|---|---|---|---|
| Priority: | Normal | ||
| Assignee: | - | ||
| Category: | Symbology | ||
| Pull Request or Patch supplied: | No | Resolution: | |
| Easy fix?: | No | Copied to github as #: | 19254 |
Description
Hi,
I would nice, to be able to create relative color tables for raster data in QGIS and save them for other layers. Newly defined gradient color ramps end up in a color table with fix values:
for example:
- QGIS Generated Color Map Export File
INTERPOLATION:INTERPOLATED
6.916,0,191,191,255,6.916000
120.812,0,255,0,255,120.811600
234.707,255,255,0,255,234.707200
348.603,255,127,0,255,348.602800
462.498,191,127,63,255,462.498400
576.394,20,20,20,255,576.394000
it would be great to save it as relative color values, as defined in the gradient color ramps dialog.
- QGIS Generated Color Map Export File
INTERPOLATION:INTERPOLATED
0%,0,191,191,255
10%,0,255,0,255
30%,255,255,0,255
60%,255,127,0,255
80%,191,127,63,255
100%,20,20,20,255
and even better would be the option to create a mixed color table with fix values and percentage.
- QGIS Generated Color Map Export File
INTERPOLATION:INTERPOLATED
0,0,191,191,255
60,0,255,0,255
30%,255,255,0,255
300,255,127,0,255
80%,191,127,63,255
100%,20,20,20,255
Is it possible to define such color tables in a text file and import it for
a raster layer? Or how would this be done?
Thanks a lot
Otto
History
#1
Updated by Paolo Cavallini over 10 years ago
also the reverse should be done: currently when applying a colour ramp to a raster, this gets stretched from min-max, which is not always appropriate (e.g. DTM ramps should be applied as absolute values, so that top of hills should not be white).
In short, I think we should extend our model for ramps, allowing users to define both absolute and relative ramps, both when creating and when applying them.
GRASS could be a good guide for this.
#2
Updated by Giovanni Manghi over 7 years ago
- Easy fix? set to No