added logging

ultralytics/data/loaders.py

@@ -249,6 +249,7 @@ class LoadImages:
         else:
             # Read image
             self.count += 1
+            print("Grayscale image loading...")
             im0 = cv2.imread(path, cv2.IMREAD_GRAYSCALE)  # BGR
             if im0 is None:
                 raise FileNotFoundError(f'Image Not Found {path}')