How to convert a NumPy array to PIL image applying matplotlib colormap

Quite a busy one-liner, but here it is:

  1. First ensure your NumPy array, myarray, is normalised with the max value at 1.0.
  2. Apply the colormap directly to myarray.
  3. Rescale to the 0-255 range.
  4. Convert to integers, using np.uint8().
  5. Use Image.fromarray().

And you’re done:

from PIL import Image
from matplotlib import cm
im = Image.fromarray(np.uint8(cm.gist_earth(myarray)*255))

with plt.savefig():

Enter image description here

with im.save():

Enter image description here

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