diff --git a/bob/ip/binseg/test/test_transforms.py b/bob/ip/binseg/test/test_transforms.py
index 799ea43a73bb90e714b915d2535e9c173e5e11ba..cad62350df39f01c0eb0996470cfae366ebcebf0 100644
--- a/bob/ip/binseg/test/test_transforms.py
+++ b/bob/ip/binseg/test/test_transforms.py
@@ -352,7 +352,7 @@ def test_color_jitter():
 
 def test_blur():
 
-    im_size = (3, 24, 42)  # (planes, height, width)
+    im_size = (1, 256, 256)  # (planes, height, width)
     transforms = GaussianBlur(p=1)
     img = _create_img(im_size)