diff --git a/datasets/raise/split_and_compare_prnus_of_subgroups.py b/datasets/raise/split_and_compare_prnus_of_subgroups.py
index c3c2bac..f656b89 100644
--- a/datasets/raise/split_and_compare_prnus_of_subgroups.py
+++ b/datasets/raise/split_and_compare_prnus_of_subgroups.py
@@ -37,7 +37,7 @@ for subgroupIndex in range(NUMBER_OF_SUBGROUPS):
     # Not efficient mean computation.
     for numberOfImagesIndex, numberOfImages in enumerate(numberOfImagesThresholds):
         subgroupPrnuEstimateNpArray += [np.array(imagesPrnuEstimateNpArray[:numberOfImages]).mean(axis = 0)]
-        toPilImage(subgroupPrnuEstimateNpArray[-1]).save('prnu.png')
+        plt.imsave('prnu.png', subgroupPrnuEstimateNpArray[-1])
     subgroupsPrnuEstimatesNpArray += [subgroupPrnuEstimateNpArray]
 
 rmss = []