diff --git a/opensora/datasets/datasets.py b/opensora/datasets/datasets.py
index 9287c70..43ee214 100644
--- a/opensora/datasets/datasets.py
+++ b/opensora/datasets/datasets.py
@@ -68,7 +68,7 @@ class VideoTextDataset(torch.utils.data.Dataset):
 
         if file_type == "video":
             # loading
-            vframes, vinfo = read_video(path, backend='cv2')
+            vframes, vinfo = read_video(path, backend='av')
             video_fps = vinfo["video_fps"] if 'video_fps' in vinfo else 24
 
             # Sampling video frames
@@ -145,7 +145,7 @@ class VariableVideoTextDataset(VideoTextDataset):
         video_fps = 24  # default fps
         if file_type == "video":
             # loading
-            vframes, vinfo = read_video(path, backend='cv2')
+            vframes, vinfo = read_video(path, backend='av')
             video_fps = vinfo["video_fps"] if 'video_fps' in vinfo else 24
 
             # Sampling video frames