Update app.py

app.py

@@ -5,6 +5,9 @@ import shutil
 
 # Function to execute the anime upscaler command
 def execute_upscaler(input_video_path, output_path, save_intermediate, async_mode):
+    if input_video_path is None:
+        raise ValueError("No video file provided.")
+
     # Determine the path to the model file in the same directory
     script_directory = os.path.dirname(os.path.realpath(__file__))
     model_path = os.path.join(script_directory, "RealESRGAN_x4plus_anime_6B.pth")