Python Display GeoTIFF File – How to Display GeoTIFF File in Python Using Rasterio and Matplotlib

Question

I have a list of GeoTIFF files, which I uploaded to a repo in Github. The files are generated in R, there I can read them with the raster library :

> library(raster)
Loading required package: sp 
> r = (raster::raster("./2020-07-24_B.tif"))
class      : RasterLayer 
dimensions : 36, 28, 1008  (nrow, ncol, ncell)
resolution : 10, 10  (x, y)
extent     : 680460, 680740, 4183700, 4184060  (xmin, xmax, ymin, ymax)
crs        : +proj=utm +zone=30 +datum=WGS84 +units=m +no_defs 
source     : 2020-07-24_B.tif 
names      : X2020.07.24_B 
values     : 687, 1494  (min, max)

raster::plot(r)

The files load nicely in QGIS:

But I am unable to make them work in Python:

import rasterio as rs
from matplotlib import pyplot

file = "B/2020-07-24_B.tif"
raster = rs.open(file)
array = raster.read()
pyplot.imshow(array[0])

I followed this tutorial.

At this point I wonder if the file could be corrupted in some way or is just an issue related with the tweaking of imshow params.

Answer 1

Yes. It is just an issue related with the parameters. Without vmin and vmax, matplotlib uses nodata value as minimum value, and stretches the color map.

So, you need to specify min and max value:

pyplot.imshow(array[0], vmin=687, vmax=array[0].max())

Instead of pyplot.imshow, you can use rasterio show method.

from rasterio.plot import show
show(raster)