more changes

src/lerobot/envs/libero.py

@@ -276,6 +276,13 @@ class LiberoEnv(gym.Env):
             return {"pixels": images.copy()}
 
         if self.obs_type == "pixels_agent_pos":
+            # Validate required fields are present
+            if eef_pos is None or eef_quat is None or gripper_qpos is None:
+                raise ValueError(
+                    f"Missing required robot state fields in raw observation. "
+                    f"Got eef_pos={eef_pos is not None}, eef_quat={eef_quat is not None}, "
+                    f"gripper_qpos={gripper_qpos is not None}"
+                )
             return obs
 
         raise NotImplementedError(

src/lerobot/processor/observation_processor.py

@@ -223,6 +223,10 @@ class LiberoProcessorStep(ObservationProcessorStep):
         - End-effector quaternion converted to axis-angle (3D)
         - Gripper joint positions (2D)
     -   Maps the concatenated state to `"observation.state"`.
+
+    **Image Processing:**
+    -   Rotates images by 180 degrees by flipping both height and width dimensions.
+    -   This accounts for the HuggingFaceVLA/libero camera orientation convention.
     """
 
     def _process_observation(self, observation):