diff --git a/cista/preview.py b/cista/preview.py
index 906c64a..2c9a2fb 100644
--- a/cista/preview.py
+++ b/cista/preview.py
@@ -207,7 +207,13 @@ def process_video(path, *, maxsize, quality):
         t_save_start = perf_counter()
         crf = str(int(63 * (1 - quality / 100) ** 2))  # Closely matching PIL quality-%
         ostream = ocontainer.add_stream(
-            "av1", options={"crf": crf, "usage": "realtime"}
+            "av1",
+            options={
+                "crf": crf,
+                "usage": "realtime",
+                "cpu-used": "8",
+                "threads": "1",
+            },
         )
         assert isinstance(ostream, av.VideoStream)
         ostream.width = frame.width