diff --git a/cista/preview.py b/cista/preview.py
index d8de724..d8b4f2b 100644
--- a/cista/preview.py
+++ b/cista/preview.py
@@ -99,7 +99,7 @@ def process_pdf(path, *, maxsize, maxzoom, quality, page_number=0):
 def process_video(path, *, maxsize, quality):
     frame = None
     imgdata = io.BytesIO()
-    istream = ostream = icontainer = ocontainer = icc = occ = frame = None
+    istream = ostream = icc = occ = frame = None
     with (
         av.open(str(path)) as icontainer,
         av.open(imgdata, "w", format="avif") as ocontainer,