feat: added abstract class for FrameCapturer

client/models/pose_detection/frame_capturer.py

@@ -0,0 +1,32 @@
+from abc import ABC, abstractmethod
+
+import numpy as np
+import cv2
+
+
+class FrameCapturer(ABC):
+    """Provides an interface to video frames for a PostureTracker."""
+
+    @abstractmethod
+    def get_frame(self) -> tuple[np.ndarray, int]:
+        """
+        Returns:
+            (frame, timestamp), image is an image frame in the format HxWxC. Where the channels are
+                in RGB format. Timestamp is in milliseconds.
+        """
+
+
+class OpenCVCapturer(FrameCapturer):
+    """FrameCapturer using OpenCV to read from camera."""
+
+    def __init__(self) -> None:
+        self._cam = cv2.VideoCapture(0)
+
+    def get_frame(self) -> tuple[np.ndarray, int]:
+        _, frame = self._cam.read()
+        timestamp = self._cam.get(cv2.CAP_PROP_POS_MSEC)
+        return frame, timestamp
+
+    def release(self) -> None:
+        """Release the camera."""
+        self._cam.release()