diff --git a/src/ffx/ffx_controller.py b/src/ffx/ffx_controller.py
index ade3cad..7d70aa3 100644
--- a/src/ffx/ffx_controller.py
+++ b/src/ffx/ffx_controller.py
@@ -59,7 +59,7 @@ class FfxController():
     def generateH264Tokens(self, quality, subIndex : int = 0):
 
         return [f"-c:v:{int(subIndex)}", 'libx264',
-                "-preset", "slow"
+                "-preset", "slow",
                 f"crf={quality}"]