update

shadows.py

@@ -338,10 +338,10 @@ def build_gradio_interface():
         def store_original(img, orig):
             """Store the original image when a new image is uploaded."""
             if img is not None:
-                return img, img  # Store the new image as original
-            return img, orig  # Keep existing original if no new image
+                return img  # Store the new image as original
+            return orig  # Keep existing original if no new image
 
-        img_in.change(store_original, inputs=[img_in, original_image], outputs=[img_in, original_image])
+        img_in.change(store_original, inputs=[img_in, original_image], outputs=[original_image])
 
         # link buttons to mode change
         start_y.click(on_mode_change, inputs=[gr.State("yellow"), img_in, current_mode, current_points, y_lines, r_lines, y_pairs, r_pairs],