diff --git a/notebook/requirements.txt b/notebook/requirements.txt
index c3d9758..846495c 100644
--- a/notebook/requirements.txt
+++ b/notebook/requirements.txt
@@ -18,7 +18,7 @@ tensorflow==2.0.0b1
 seaborn==0.10.1
 h5py==2.10.0
 opencv-python==4.2.0.34
-opencv-contrib-python-nonfree==4.1.1.1
+opencv-contrib-python==3.4.2.1
 easydict==1.9
 Pillow==7.1.2
 spacy==2.2.4
diff --git a/restricted-notebook/requirements.txt b/restricted-notebook/requirements.txt
index 934f951..ea6f1da 100644
--- a/restricted-notebook/requirements.txt
+++ b/restricted-notebook/requirements.txt
@@ -15,7 +15,7 @@ tensorflow==2.0.0b1
 seaborn==0.10.1
 h5py==2.10.0
 opencv-python==4.2.0.34
-opencv-contrib-python-nonfree==4.1.1.1
+opencv-contrib-python==3.4.2.1
 easydict==1.9
 Pillow==7.1.2
 spacy==2.2.4