Update app.py

app.py

@@ -107,7 +107,7 @@ with gr.Blocks() as iface:
     download_output = gr.File(label="Download Binary Mask (.tif)")
 
     with gr.Row():
-        slice_slider = gr.Slider(minimum=0, maximum=np.shape(processed_image)[2], step=1, label="Slice Index", interactive=True)
+        slice_slider = gr.Slider(minimum=0, maximum=np.shape(processed_image)[2] if processed_image else 100, step=1, label="Slice Index", interactive=True)
         visualization_output = gr.Plot(label="2D Slice Visualization")
 
     # Button click triggers segmentation