diff --git a/src/motion_detector.py b/src/motion_detector.py
index 9a50122..0861944 100644
--- a/src/motion_detector.py
+++ b/src/motion_detector.py
@@ -287,6 +287,8 @@ def detections_from_gray_imgs(self, gray1, gray2):
             area = (ymax - ymin) * (xmax - xmin)
             if area < self.min_box_size:
                 continue
+            if self.max_box_size is not None and area > self.max_box_size:
+                continue
 
             detections.append(
                 {