Reading colors on map using PyQGIS

Question

I am trying to read the RGB values at certain locations on my map which is a .tif-file I brought into QGIS.

Goal: match species presence points on my map to certain RGB values on the .tif-file.

from PIL import Image
img = PIL.Image.open(iface.layerTreeView().selectedLayers())
col = img.convert("RGB")
val = col.getpixel((0,0)) #tried to read value at center
print (val)

And getting the error:

AttributeError: 'list' object has no attribute 'read'

You have a raster layer and should use those methods to access the pixesl — Ian Turton, Aug 13 '20 at 19:23

score 1 · Accepted Answer · edited Aug 13 '20 at 20:26

Right now, I think you are trying to pass a raster as an input to the .open function, which is not an acceptable parameter.

According to the documentation for the Image module, parameters are:

fp – A filename (string), pathlib.Path object or a file object. The file object must implement read(), seek(), and tell() methods, and be opened in binary mode.
mode – The mode. If given, this argument must be "r".

Try putting the .tif filename directly into the line, like this:

img = PIL.Image.open("image.tif")

Or providing the full path name as a parameter, like this:

img = PIL.Image.open(r"C:\temp\image.tif")

Perhaps you might also consider using GDAL to accomplish your tasks. There is an answer here that might help get you started with that.

If the answer was useful, please mark it as the answer. Thanks! — MarcM, Aug 14 '20 at 06:42

Reading colors on map using PyQGIS

1 Answers1