Update engine.py

engine.py

@@ -90,6 +90,7 @@ class Engine:
         cap = cv2.VideoCapture(video)
         video_writer = None
         frames = []
+        output_file = "output_video.mp4"
         
         while True:
             ret, frame = cap.read()
@@ -99,7 +100,6 @@ class Engine:
             
             if video_writer is None:
                 height, width, _ = frame.shape
-                output_file = "output_video.mp4"
                 fourcc = cv2.VideoWriter_fourcc(*'mp4v')
                 video_writer = cv2.VideoWriter(output_file, fourcc, 24.0, (width, height))