diff --git a/src/llamafactory/data/aligner.py b/src/llamafactory/data/aligner.py
index 0e497ebc..87d3729e 100644
--- a/src/llamafactory/data/aligner.py
+++ b/src/llamafactory/data/aligner.py
@@ -33,41 +33,47 @@ logger = get_logger(__name__)
 
 
 def _convert_images(
-    images: Sequence["ImageInput"],
+    images: Union["ImageInput", Sequence["ImageInput"]],
     dataset_attr: "DatasetAttr",
     data_args: "DataArguments",
 ) -> Optional[List["ImageInput"]]:
     r"""
     Optionally concatenates image path to dataset dir when loading from local disk.
     """
-    if len(images) == 0:
+    if not isinstance(images, list):
+        images = [images]
+    elif len(images) == 0:
         return None
+    else:
+        images = images[:]
 
-    images = images[:]
     if dataset_attr.load_from in ["script", "file"]:
         for i in range(len(images)):
-            if isinstance(images[i], str) and os.path.isfile(os.path.join(data_args.dataset_dir, images[i])):
-                images[i] = os.path.join(data_args.dataset_dir, images[i])
+            if isinstance(images[i], str) and os.path.isfile(os.path.join(data_args.image_dir, images[i])):
+                images[i] = os.path.join(data_args.image_dir, images[i])
 
     return images
 
 
 def _convert_videos(
-    videos: Sequence["VideoInput"],
+    videos: Union["VideoInput", Sequence["VideoInput"]],
     dataset_attr: "DatasetAttr",
     data_args: "DataArguments",
 ) -> Optional[List["VideoInput"]]:
     r"""
     Optionally concatenates video path to dataset dir when loading from local disk.
     """
-    if len(videos) == 0:
+    if not isinstance(videos, list):
+        videos = [videos]
+    elif len(videos) == 0:
         return None
+    else:
+        videos = videos[:]
 
-    videos = videos[:]
     if dataset_attr.load_from in ["script", "file"]:
         for i in range(len(videos)):
-            if isinstance(videos[i], str) and os.path.isfile(os.path.join(data_args.dataset_dir, videos[i])):
-                videos[i] = os.path.join(data_args.dataset_dir, videos[i])
+            if isinstance(videos[i], str) and os.path.isfile(os.path.join(data_args.image_dir, videos[i])):
+                videos[i] = os.path.join(data_args.image_dir, videos[i])
 
     return videos
 
diff --git a/src/llamafactory/hparams/data_args.py b/src/llamafactory/hparams/data_args.py
index 1adcf2d0..7c89c016 100644
--- a/src/llamafactory/hparams/data_args.py
+++ b/src/llamafactory/hparams/data_args.py
@@ -41,6 +41,10 @@ class DataArguments:
         default="data",
         metadata={"help": "Path to the folder containing the datasets."},
     )
+    image_dir: Optional[str] = field(
+        default=None,
+        metadata={"help": "Path to the folder containing the images or videos. Defaults to `dataset_dir`."},
+    )
     cutoff_len: int = field(
         default=1024,
         metadata={"help": "The cutoff length of the tokenized inputs in the dataset."},
@@ -111,7 +115,13 @@ class DataArguments:
     )
     tokenized_path: Optional[str] = field(
         default=None,
-        metadata={"help": "Path to save or load the tokenized datasets."},
+        metadata={
+            "help": (
+                "Path to save or load the tokenized datasets. "
+                "If tokenized_path not exists, it will save the tokenized datasets. "
+                "If tokenized_path exists, it will load the tokenized datasets."
+            )
+        },
     )
 
     def __post_init__(self):
@@ -123,6 +133,9 @@ class DataArguments:
         self.dataset = split_arg(self.dataset)
         self.eval_dataset = split_arg(self.eval_dataset)
 
+        if self.image_dir is None:
+            self.image_dir = self.dataset_dir
+
         if self.dataset is None and self.val_size > 1e-6:
             raise ValueError("Cannot specify `val_size` if `dataset` is None.")