Update app.py

app.py

@@ -50,10 +50,13 @@ app_ui = ui.page_fluid(
 
 @module.ui
 def plot_ui():
-    return ui.column(4, ui.output_plot("plot_prediction"))
+    return ui.div(
+        ui.input_slider("opacity", "Opacity", 0, 1.0, 0.5),
+        ui.column(4, ui.output_plot("plot_prediction"))
+    )
 
 @module.server
-def plot_server(input, output, session, r, opacity):
+def plot_server(input, output, session, r):
     @render.plot
     def plot_prediction():
         fig, ax = plt.subplots()
@@ -76,7 +79,7 @@ def plot_server(input, output, session, r, opacity):
 
         out = v.overlay_instances(masks = r["instances"].pred_masks.to("cpu"),
                                   assigned_colors = colours, 
-                                  alpha = opacity)
+                                  alpha = input.opacity())
 
         ax.imshow(cv2.cvtColor(out.get_image()[:, :, ::-1], cv2.COLOR_BGR2RGB))
 
@@ -136,9 +139,8 @@ def server(input, output, session: Session):
         for idx, r in enumerate(results):
 
             id = "image_" + str(idx)
-            opacity = ui.input_slider(id, "Opacity", 0, 1.0, 0.5)
 
-            plot_server(f"plot_{idx}",r=r, opacity=0.5)
+            plot_server(f"plot_{idx}", r=r)
             
             ui_output.append(
                 ui.div(
@@ -146,7 +148,6 @@ def server(input, output, session: Session):
                         ui.column(4, ui.img(src=f"data:image/png;base64,{r['image_base64']}")),
                         plot_ui(f"plot_{idx}"),
                     ),
-                    opacity,
                     ui.h5(r['filename'], style="margin-top: 15px;"),
                     ui.div(
                         ui.span(f"Viable = {r.get('viable', '? ')}", style="margin: 0 15px;"),