refactor(cameras): add warm-up, fix defaul args, remove width and height from find_cameras utils

lerobot/common/cameras/configs.py

@@ -33,7 +33,7 @@ class Cv2Rotation(Enum):
     ROTATE_270 = -90
 
 
-@dataclass
+@dataclass(kw_only=True)
 class CameraConfig(draccus.ChoiceRegistry, abc.ABC):
     fps: int | None = None
     width: int | None = None

lerobot/common/cameras/intel/camera_realsense.py

@@ -336,6 +336,10 @@ class RealSenseCamera(Camera):
 
         logger.debug(f"Validating stream configuration for {self.serial_number}...")
         self._validate_capture_settings()
+
+        logger.debug(f"Reading a warm-up frame for {self.serial_number}...")
+        self.read()  # NOTE(Steven): For now we just read one frame, we could also loop for X secs
+
         logger.info(f"Camera {self.serial_number} connected and configured successfully.")
 
     def _validate_fps(self, stream) -> None:
@@ -396,7 +400,7 @@ class RealSenseCamera(Camera):
 
     def read(
         self, color_mode: ColorMode | None = None, timeout_ms: int = 5000
-    ) -> Union[np.ndarray, Tuple[np.ndarray, np.ndarray]]:
+    ) -> np.ndarray | Tuple[np.ndarray, np.ndarray]:
         """
         Reads a single frame (color and optionally depth) synchronously from the camera.
 

lerobot/common/cameras/opencv/camera_opencv.py

@@ -205,6 +205,10 @@ class OpenCVCamera(Camera):
 
         logger.debug(f"Successfully opened camera {self.index_or_path}. Applying configuration...")
         self._configure_capture_settings()
+
+        logger.debug(f"Reading a warm-up frame for {self.serial_number}...")
+        self.read()  # NOTE(Steven): For now we just read one frame, we could also loop for X secs\
+
         logger.debug(f"Camera {self.index_or_path} connected and configured successfully.")
 
     def _validate_fps(self) -> None:

lerobot/common/cameras/opencv/configuration_opencv.py

@@ -1,4 +1,4 @@
-from dataclasses import dataclass, field
+from dataclasses import dataclass
 from pathlib import Path
 
 from ..configs import CameraConfig, ColorMode, Cv2Rotation
@@ -18,9 +18,7 @@ class OpenCVCameraConfig(CameraConfig):
     ```
     """
 
-    index_or_path: int | Path = field(
-        default=...,
-    )
+    index_or_path: int | Path
     color_mode: ColorMode = ColorMode.RGB
     channels: int = 3  # NOTE(Steven): Why is this a config?
     rotation: Cv2Rotation = Cv2Rotation.NO_ROTATION