(depth image processing): excluding depth frames from the RGB to BGR image processing (#4135)

* (depth image processing): excluding depth frames from the RGB to BGR image processing

* test(update): updating tests to include RGB/BGR conversion checks

tests/cameras/test_opencv.py

@@ -26,7 +26,7 @@ import cv2
 import numpy as np
 import pytest
 
-from lerobot.cameras.configs import Cv2Rotation
+from lerobot.cameras.configs import ColorMode, Cv2Rotation
 from lerobot.cameras.opencv import OpenCVCamera, OpenCVCameraConfig
 from lerobot.utils.errors import DeviceAlreadyConnectedError, DeviceNotConnectedError
 
@@ -132,6 +132,28 @@ def test_read(index_or_path):
         assert isinstance(img, np.ndarray)
 
 
+@pytest.mark.parametrize("index_or_path", TEST_IMAGE_PATHS, ids=TEST_IMAGE_SIZES)
+def test_color_mode_conversion(index_or_path):
+    """RGB and BGR reads of the same frame must differ only by a channel-axis reversal."""
+    rgb_config = OpenCVCameraConfig(index_or_path=index_or_path, color_mode=ColorMode.RGB, warmup_s=0)
+    bgr_config = OpenCVCameraConfig(index_or_path=index_or_path, color_mode=ColorMode.BGR, warmup_s=0)
+    with OpenCVCamera(rgb_config) as rgb_cam:
+        rgb = rgb_cam.read()
+    with OpenCVCamera(bgr_config) as bgr_cam:
+        bgr = bgr_cam.read()
+
+    assert rgb.shape == bgr.shape
+    np.testing.assert_array_equal(rgb, bgr[..., ::-1])
+
+
+def test_postprocess_invalid_color_mode():
+    config = OpenCVCameraConfig(index_or_path=DEFAULT_PNG_FILE_PATH)
+    camera = OpenCVCamera(config)
+    camera.color_mode = "invalid"
+    with pytest.raises(ValueError):
+        camera._postprocess_image(np.zeros((120, 160, 3), dtype=np.uint8))
+
+
 def test_read_before_connect():
     config = OpenCVCameraConfig(index_or_path=DEFAULT_PNG_FILE_PATH)