Update app.py

app.py

@@ -154,7 +154,7 @@ with gr.Blocks(js=js, css=css) as demo:
         </svg>
         """)
         scale = gr.Slider(label="Scale", minimum="-128", maximum="128", value="0", step="1", elem_id="scale")
-        gray_depth.change(fn=None, inputs=[original_image, gray_depth], outputs=None, js=load_svg)
+        gray_depth_file.change(fn=None, inputs=[original_image, gray_depth], outputs=None, js=load_svg)
         tmp_gray_depth = tempfile.NamedTemporaryFile(suffix='.png', delete=False)
         gray_depth.save(tmp_gray_depth.name)