feat(dataset): add streaming video encoding + HW encoder support (#2974)

* feat(dataset): init stream encoding

* feat(dataset): use threads to fix frame pickle latency

* refactor(dataset): remove HW encoded related changes

* add lp (#2977)

* feat(dataset): add Hw encoding + log drop frames (#2978)

* chore(docs): add streaming video encoding guide

* fix(dataset): style docs + testing

* chore(docs): simplify sttreaming video encoding guide

* chore(dataset): add commands + streaming encoding default false + print note if false + queue default is now 30

* chore(docs): add verification note advice

* chore(dataset): adjusting defaults & docs for streaming encoding

* docs(scripts): improve docstrings

* test(dataset): polish streaming encoding tests

* chore(dataset): move FYI log related to streaming

* chore(dataset): add arg vcodec to suggestions

* refactor(dataset): better handling for auto and available vcodec

* chore(dataset): change log level

* docs(dataset): add note related to training performance vcodec

* docs(dataset): add more notes to streaming encoding

---------

Co-authored-by: Caroline Pascal <caroline8.pascal@gmail.com>
Co-authored-by: Pepijn <pepijn@huggingface.co>
This commit is contained in:
Steven Palma
2026-02-23 13:57:43 +01:00
committed by GitHub
parent 5865170d36
commit e96339a3b4
16 changed files with 1532 additions and 55 deletions
+109 -15
View File
@@ -68,6 +68,7 @@ from lerobot.datasets.utils import (
write_tasks,
)
from lerobot.datasets.video_utils import (
StreamingVideoEncoder,
VideoFrame,
concatenate_video_files,
decode_video_frames,
@@ -75,11 +76,11 @@ from lerobot.datasets.video_utils import (
get_safe_default_codec,
get_video_duration_in_s,
get_video_info,
resolve_vcodec,
)
from lerobot.utils.constants import HF_LEROBOT_HOME
CODEBASE_VERSION = "v3.0"
VALID_VIDEO_CODECS = {"h264", "hevc", "libsvtav1"}
class LeRobotDatasetMetadata:
@@ -545,12 +546,19 @@ class LeRobotDatasetMetadata:
def _encode_video_worker(
video_key: str, episode_index: int, root: Path, fps: int, vcodec: str = "libsvtav1"
video_key: str,
episode_index: int,
root: Path,
fps: int,
vcodec: str = "libsvtav1",
encoder_threads: int | None = None,
) -> Path:
temp_path = Path(tempfile.mkdtemp(dir=root)) / f"{video_key}_{episode_index:03d}.mp4"
fpath = DEFAULT_IMAGE_PATH.format(image_key=video_key, episode_index=episode_index, frame_index=0)
img_dir = (root / fpath).parent
encode_video_frames(img_dir, temp_path, fps, vcodec=vcodec, overwrite=True)
encode_video_frames(
img_dir, temp_path, fps, vcodec=vcodec, overwrite=True, encoder_threads=encoder_threads
)
shutil.rmtree(img_dir)
return temp_path
@@ -570,6 +578,9 @@ class LeRobotDataset(torch.utils.data.Dataset):
video_backend: str | None = None,
batch_encoding_size: int = 1,
vcodec: str = "libsvtav1",
streaming_encoding: bool = False,
encoder_queue_maxsize: int = 30,
encoder_threads: int | None = None,
):
"""
2 modes are available for instantiating this class, depending on 2 different use cases:
@@ -683,12 +694,17 @@ class LeRobotDataset(torch.utils.data.Dataset):
batch_encoding_size (int, optional): Number of episodes to accumulate before batch encoding videos.
Set to 1 for immediate encoding (default), or higher for batched encoding. Defaults to 1.
vcodec (str, optional): Video codec for encoding videos during recording. Options: 'h264', 'hevc',
'libsvtav1'. Defaults to 'libsvtav1'. Use 'h264' for faster encoding on systems where AV1
encoding is CPU-heavy.
'libsvtav1', 'auto', or hardware-specific codecs like 'h264_videotoolbox', 'h264_nvenc'.
Defaults to 'libsvtav1'. Use 'auto' to auto-detect the best available hardware encoder.
streaming_encoding (bool, optional): If True, encode video frames in real-time during capture
instead of writing PNG images first. This makes save_episode() near-instant. Defaults to False.
encoder_queue_maxsize (int, optional): Maximum number of frames to buffer per camera when using
streaming encoding. Defaults to 30 (~1s at 30fps).
encoder_threads (int | None, optional): Number of threads per encoder instance. None lets the
codec auto-detect (default). Lower values reduce CPU usage per encoder. Maps to 'lp' (via svtav1-params) for
libsvtav1 and 'threads' for h264/hevc.
"""
super().__init__()
if vcodec not in VALID_VIDEO_CODECS:
raise ValueError(f"Invalid vcodec '{vcodec}'. Must be one of: {sorted(VALID_VIDEO_CODECS)}")
self.repo_id = repo_id
self.root = Path(root) if root else HF_LEROBOT_HOME / repo_id
self.image_transforms = image_transforms
@@ -700,7 +716,8 @@ class LeRobotDataset(torch.utils.data.Dataset):
self.delta_indices = None
self.batch_encoding_size = batch_encoding_size
self.episodes_since_last_encoding = 0
self.vcodec = vcodec
self.vcodec = resolve_vcodec(vcodec)
self._encoder_threads = encoder_threads
# Unused attributes
self.image_writer = None
@@ -708,6 +725,7 @@ class LeRobotDataset(torch.utils.data.Dataset):
self.writer = None
self.latest_episode = None
self._current_file_start_frame = None # Track the starting frame index of the current parquet file
self._streaming_encoder = None
self.root.mkdir(exist_ok=True, parents=True)
@@ -749,6 +767,19 @@ class LeRobotDataset(torch.utils.data.Dataset):
check_delta_timestamps(self.delta_timestamps, self.fps, self.tolerance_s)
self.delta_indices = get_delta_indices(self.delta_timestamps, self.fps)
# Initialize streaming encoder for resumed recording
if streaming_encoding and len(self.meta.video_keys) > 0:
self._streaming_encoder = StreamingVideoEncoder(
fps=self.meta.fps,
vcodec=self.vcodec,
pix_fmt="yuv420p",
g=2,
crf=30,
preset=None,
queue_maxsize=encoder_queue_maxsize,
encoder_threads=encoder_threads,
)
def _close_writer(self) -> None:
"""Close and cleanup the parquet writer if it exists."""
writer = getattr(self, "writer", None)
@@ -1104,6 +1135,8 @@ class LeRobotDataset(torch.utils.data.Dataset):
"""
self._close_writer()
self.meta._close_writer()
if self._streaming_encoder is not None:
self._streaming_encoder.close()
def create_episode_buffer(self, episode_index: int | None = None) -> dict:
current_ep_idx = self.meta.total_episodes if episode_index is None else episode_index
@@ -1158,6 +1191,13 @@ class LeRobotDataset(torch.utils.data.Dataset):
self.episode_buffer["timestamp"].append(timestamp)
self.episode_buffer["task"].append(frame.pop("task")) # Remove task from frame after processing
# Start streaming encoder on first frame of episode (once, before iterating keys)
if frame_index == 0 and self._streaming_encoder is not None:
self._streaming_encoder.start_episode(
video_keys=list(self.meta.video_keys),
temp_dir=self.root,
)
# Add frame features to episode_buffer
for key in frame:
if key not in self.features:
@@ -1165,7 +1205,10 @@ class LeRobotDataset(torch.utils.data.Dataset):
f"An element of the frame is not in the features. '{key}' not in '{self.features.keys()}'."
)
if self.features[key]["dtype"] in ["image", "video"]:
if self.features[key]["dtype"] == "video" and self._streaming_encoder is not None:
self._streaming_encoder.feed_frame(key, frame[key])
self.episode_buffer[key].append(None) # Placeholder (video keys are skipped in parquet)
elif self.features[key]["dtype"] in ["image", "video"]:
img_path = self._get_image_file_path(
episode_index=self.episode_buffer["episode_index"], image_key=key, frame_index=frame_index
)
@@ -1226,13 +1269,38 @@ class LeRobotDataset(torch.utils.data.Dataset):
# Wait for image writer to end, so that episode stats over images can be computed
self._wait_image_writer()
ep_stats = compute_episode_stats(episode_buffer, self.features)
ep_metadata = self._save_episode_data(episode_buffer)
has_video_keys = len(self.meta.video_keys) > 0
use_streaming = self._streaming_encoder is not None and has_video_keys
use_batched_encoding = self.batch_encoding_size > 1
if has_video_keys and not use_batched_encoding:
if use_streaming:
# Compute stats for non-video features only (video stats come from encoder)
non_video_buffer = {
k: v
for k, v in episode_buffer.items()
if self.features.get(k, {}).get("dtype") not in ("video",)
}
non_video_features = {k: v for k, v in self.features.items() if v["dtype"] != "video"}
ep_stats = compute_episode_stats(non_video_buffer, non_video_features)
else:
ep_stats = compute_episode_stats(episode_buffer, self.features)
ep_metadata = self._save_episode_data(episode_buffer)
if use_streaming:
# Finish streaming encoding and collect results
streaming_results = self._streaming_encoder.finish_episode()
for video_key in self.meta.video_keys:
temp_path, video_stats = streaming_results[video_key]
if video_stats is not None:
# Format stats same as compute_episode_stats: normalize to [0,1], reshape to (C,1,1)
ep_stats[video_key] = {
k: v if k == "count" else np.squeeze(v.reshape(1, -1, 1, 1) / 255.0, axis=0)
for k, v in video_stats.items()
}
ep_metadata.update(self._save_episode_video(video_key, episode_index, temp_path=temp_path))
elif has_video_keys and not use_batched_encoding:
num_cameras = len(self.meta.video_keys)
if parallel_encoding and num_cameras > 1:
# TODO(Steven): Ideally we would like to control the number of threads per encoding such that:
@@ -1246,6 +1314,7 @@ class LeRobotDataset(torch.utils.data.Dataset):
self.root,
self.fps,
self.vcodec,
self._encoder_threads,
): video_key
for video_key in self.meta.video_keys
}
@@ -1514,6 +1583,10 @@ class LeRobotDataset(torch.utils.data.Dataset):
return metadata
def clear_episode_buffer(self, delete_images: bool = True) -> None:
# Cancel streaming encoder if active
if self._streaming_encoder is not None:
self._streaming_encoder.cancel_episode()
# Clean up image files for the current episode buffer
if delete_images:
# Wait for the async image writer to finish
@@ -1561,7 +1634,9 @@ class LeRobotDataset(torch.utils.data.Dataset):
Note: `encode_video_frames` is a blocking call. Making it asynchronous shouldn't speedup encoding,
since video encoding with ffmpeg is already using multithreading.
"""
return _encode_video_worker(video_key, episode_index, self.root, self.fps, self.vcodec)
return _encode_video_worker(
video_key, episode_index, self.root, self.fps, self.vcodec, self._encoder_threads
)
@classmethod
def create(
@@ -1578,10 +1653,12 @@ class LeRobotDataset(torch.utils.data.Dataset):
video_backend: str | None = None,
batch_encoding_size: int = 1,
vcodec: str = "libsvtav1",
streaming_encoding: bool = False,
encoder_queue_maxsize: int = 30,
encoder_threads: int | None = None,
) -> "LeRobotDataset":
"""Create a LeRobot Dataset from scratch in order to record data."""
if vcodec not in VALID_VIDEO_CODECS:
raise ValueError(f"Invalid vcodec '{vcodec}'. Must be one of: {sorted(VALID_VIDEO_CODECS)}")
vcodec = resolve_vcodec(vcodec)
obj = cls.__new__(cls)
obj.meta = LeRobotDatasetMetadata.create(
repo_id=repo_id,
@@ -1599,6 +1676,7 @@ class LeRobotDataset(torch.utils.data.Dataset):
obj.batch_encoding_size = batch_encoding_size
obj.episodes_since_last_encoding = 0
obj.vcodec = vcodec
obj._encoder_threads = encoder_threads
if image_writer_processes or image_writer_threads:
obj.start_image_writer(image_writer_processes, image_writer_threads)
@@ -1620,6 +1698,22 @@ class LeRobotDataset(torch.utils.data.Dataset):
obj._lazy_loading = False
obj._recorded_frames = 0
obj._writer_closed_for_reading = False
# Initialize streaming encoder
if streaming_encoding and len(obj.meta.video_keys) > 0:
obj._streaming_encoder = StreamingVideoEncoder(
fps=fps,
vcodec=vcodec,
pix_fmt="yuv420p",
g=2,
crf=30,
preset=None,
queue_maxsize=encoder_queue_maxsize,
encoder_threads=encoder_threads,
)
else:
obj._streaming_encoder = None
return obj