Add suggestions from code review

lerobot/common/datasets/lerobot_dataset.py

@@ -48,11 +48,10 @@ def __init__(
         repo_id: str,
         root: Path | None = None,
         episodes: list[int] | None = None,
-        split: str = "train",
         image_transforms: Callable | None = None,
         delta_timestamps: dict[list[float]] | None = None,
         tolerance_s: float = 1e-4,
-        download_data: bool = True,
+        download_videos: bool = True,
         video_backend: str | None = None,
     ):
         """LeRobotDataset encapsulates 3 main things:
@@ -64,7 +63,7 @@ def __init__(
             - hf_dataset (from datasets.Dataset), which will read any values from parquet files.
             - (optional) videos from which frames are loaded to be synchronous with data from parquet files.
 
-        3 use modes are available for this class, depending on 3 different use cases:
+        3 modes are available for this class, depending on 3 different use cases:
 
         1. Your dataset already exists on the Hugging Face Hub at the address
         https://huggingface.co/datasets/{repo_id} and is not on your local disk in the 'root' folder:
@@ -119,7 +118,6 @@ def __init__(
                 '~/.cache/huggingface/lerobot'.
             episodes (list[int] | None, optional): If specified, this will only load episodes specified by
                 their episode_index in this list. Defaults to None.
-            split (str, optional): _description_. Defaults to "train".
             image_transforms (Callable | None, optional): You can pass standard v2 image transforms from
                 torchvision.transforms.v2 here which will be applied to visual modalities (whether they come
                 from videos or images). Defaults to None.
@@ -129,19 +127,18 @@ def __init__(
                 timestamps is separated to the next by 1/fps +/- tolerance_s. This also applies to frames
                 decoded from video files. It is also used to check that `delta_timestamps` (when provided) are
                 multiples of 1/fps. Defaults to 1e-4.
-            download_data (bool, optional): Flag to download actual data. Defaults to True.
+            download_videos (bool, optional): Flag to download the videos. Defaults to True.
             video_backend (str | None, optional): Video backend to use for decoding videos. There is currently
                 a single option which is the pyav decoder used by Torchvision. Defaults to pyav.
         """
         super().__init__()
         self.repo_id = repo_id
         self.root = root if root is not None else LEROBOT_HOME / repo_id
-        self.split = split
         self.image_transforms = image_transforms
         self.delta_timestamps = delta_timestamps
         self.episodes = episodes
         self.tolerance_s = tolerance_s
-        self.download_data = download_data
+        self.download_videos = download_videos
         self.video_backend = video_backend if video_backend is not None else "pyav"
         self.delta_indices = None
 
@@ -152,13 +149,6 @@ def __init__(
         self.stats = load_stats(repo_id, self._version, self.root)
         self.tasks = load_tasks(repo_id, self._version, self.root)
 
-        if not self.download_data:
-            # TODO(aliberts): Add actual support for this
-            # maybe use local_files_only=True or HF_HUB_OFFLINE=True
-            # see thread https://huggingface.slack.com/archives/C06ME3E7JUD/p1728637455476019
-            self.hf_dataset, self.episode_data_index = None, None
-            return
-
         # Load actual data
         self.download_episodes()
         self.hf_dataset = load_hf_dataset(self.root, self.data_path, self.total_episodes, self.episodes)
@@ -192,12 +182,13 @@ def download_episodes(self) -> None:
         # TODO(rcadene, aliberts): implement faster transfer
         # https://huggingface.co/docs/huggingface_hub/en/guides/download#faster-downloads
         files = None
+        ignore_patterns = None if self.download_videos else "videos/"
         if self.episodes is not None:
             files = [
                 self.data_path.format(episode_index=ep_idx, total_episodes=self.total_episodes)
                 for ep_idx in self.episodes
             ]
-            if len(self.video_keys) > 0:
+            if len(self.video_keys) > 0 and self.download_videos:
                 video_files = [
                     self.videos_path.format(video_key=vid_key, episode_index=ep_idx)
                     for vid_key in self.video_keys
@@ -211,6 +202,7 @@ def download_episodes(self) -> None:
             revision=self._version,
             local_dir=self.root,
             allow_patterns=files,
+            ignore_patterns=ignore_patterns,
         )
 
     @property
@@ -371,7 +363,8 @@ def __getitem__(self, idx) -> dict:
             item = {**video_frames, **item}
 
         if self.image_transforms is not None:
-            for cam in self.camera_keys:
+            image_keys = self.camera_keys if self.download_videos else self.image_keys
+            for cam in image_keys:
                 item[cam] = self.image_transforms(item[cam])
 
         return item
@@ -380,7 +373,6 @@ def __repr__(self):
         return (
             f"{self.__class__.__name__}(\n"
             f"  Repository ID: '{self.repo_id}',\n"
-            f"  Split: '{self.split}',\n"
             f"  Number of Samples: {self.num_samples},\n"
             f"  Number of Episodes: {self.num_episodes},\n"
             f"  Type: {'video (.mp4)' if self.video else 'image (.png)'},\n"