Add data guard for app

app.py

@@ -180,7 +180,6 @@ def build_gradio_app(queues, command):
                 poly = points[np.where(points[:, 2] <= 1)[0]][None, :, :]
                 points = [lt, rb, poly] if len(lt) > 0 else [poly, np.array([[[0, 0, 4]]])]
                 points = np.concatenate(points, axis=1)
-            points = (np.array([[[0, 0, 4]]]) if len(points) == 0 else points).astype("float32")
         elif prompt == 1:
             img, points = mask_img["background"][:, :, (2, 1, 0)], []
             for layer in mask_img["layers"]:
@@ -191,6 +190,8 @@ def build_gradio_app(queues, command):
             points = np.pad(points, [(0, 0), (0, 0), (0, 1)], constant_values=1)
             pad_points = np.array([[[0, 0, 4]]], "float32").repeat(points.shape[0], 0)
             points = np.concatenate([points, pad_points], axis=1)
+        img = np.zeros((480, 640, 3), dtype="uint8") if img is None else img
+        points = (np.array([[[0, 0, 4]]]) if len(points) == 0 else points).astype("float32")
         inputs = {"img": img, "points": points}
         with command.output_index.get_lock():
             command.output_index.value += 1