[GIS] Displaying numbers of single band raster layer in QGIS without additional vector layer

qgisqgis-pluginsraster

I wonder if there is a raster symbolizer in QGIS with a label option, that renders the cell values as labels of single band raster layer, a scalar field.

The standard raster symbolizer dialog in QGIS has no label option. So I use two data sources, a raster (geotiff) and a xyz-vector re-incarnation of the raster to draw the map. To be compatible with the GDAL cell addressing I use

   gdal_translate hires.tif hires-point.xyz -of xyz

and apply all the vector symbology and labeling capabilities on/to the xyz-object.

For large scalar fields, this workaround is very slow and not handy. At least I want to build a map for debugging purposes with this look.

Is there a plugin for QGIS that draws raster cells as shown above without the vector handicraft?

I use Debian Jessie Linux, QGIS Pisa 2.10 and gdal 2.0.1

I try to investigate the results of GDAL raster window operations for example (comment @Paulo).

Best Answer

this would be a great feature.

In my dreams, I could also double-click on a raster cell and set its value...

SAGA GIS can render cells like this. These instructions are for SAGA GIS 2.2.6 . There have been a few menu changes in recent versions of SAGA, but this is also possible in older versions.

Import your raster using Geoprocessing > File > Grid > Import > Import Raster
In properties, check "Show cell values" then "Apply"
Zoom right in

This screenshot shows the result...

Related Solutions

QGIS – Convert Multiband to Single Band Raster

You could use gdal_translate from the new workflow, which is under:

Raster > Conversion > Rearrange bands...

You won't be able to select the pencil as in the past, but you can select only the band you need from the UI. You also get the python code in case you want to use it in pyqgis:

gdal_translate "path/to/raster.tif" -b 1 "path/to/result.tif"

To get band 2, replace -b 1 with -b 2 etc.

Note: you may need to enable the GdalTools plugin.

QGIS – Displaying Single Band from Multi-Band Raster

This is a display issue: you want to display a continuous band using categories. You do not need to split your image to create a new new image: this can be done directly on the multiple band image, and you can add the multiple band layer multiple times on the map.

Go to layer properties > Symbology

Select singleband pseudocolor

Choose the band that you want to display

Select a color ramp

Select an interpolation method (discrete is OK)

Select a mode (I suggest quantile)

Select a number of classes

If you want to change some colors, double clic on the color. And if you want to change a threshol value, double clic on the threshold value.

As a remark, your band 6 doesn't look like the NDVI that you could derive from your image. It is more like some interpolated soil properties (or smoothed NDVI, but if you have a NIR band you could have a more precise one.)

EDIT: I now see from one of your comments that you don't use QGIS 3. In QGIS 2, this would be similar except that you must select "style" in the layer properties.

Best Answer

Related Solutions

QGIS – Convert Multiband to Single Band Raster

QGIS – Displaying Single Band from Multi-Band Raster

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