LeRobot #3177 / from_timestamp drift
English
GitHub issue filed by joonmo-han (weedmo) against huggingface-lerobot:
- Title: Cumulative floating-point drift in
from_timestampcausesFrameTimestampErroron concatenated videos - URL: https://github.com/huggingface/lerobot/issues/3177
- Opened: 2026-03-17
- Closed: 2026-07-31 (
state_reason: not_planned, closed by stale bot after 30 days idle) - Labels: bug, dataset, performance, examples, training, stale
- Reactions: 2 × 👍
Claimed problem: When many episodes are concatenated into one .mp4, decode_video_frames_torchvision can raise FrameTimestampError on later episodes because three timestamp paths diverge (parquet frame_index/fps, video PTS, and accumulated from_timestamp from get_video_duration_in_s()).
Maintainer response (pkooij, 2026-03-17): Praised the investigation; invited a PR and a regression test.
Follow-up by weedmo (2026-03-18): Opened fix PR lerobot-pr-3179 (https://github.com/huggingface/lerobot/pull/3179).
Collaborator reply (CarolinePascal, 2026-06-23): Could not reproduce; PR tests passed on main even with many episodes; argued that float drift alone is unlikely to reach a full frame (0.0333s) under normal LeRobot recording scale. Asked for a reproducible case if it reappears.
Local snapshot: raw/2026-09-26-lerobot-3177/ (issue JSON, comments JSON, PR JSON).
See also open-source-contributions and lerobot-pr-3179.
한국어
joonmo-han (weedmo)가 huggingface-lerobot에 올린 이슈입니다.
- 제목: 이어 붙인 비디오에서
from_timestamp누적 부동소수점 드리프트로FrameTimestampError발생 - URL: https://github.com/huggingface/lerobot/issues/3177
- 생성: 2026-03-17
- 종료: 2026-07-31 (30일 무활동 stale 봇,
not_planned) - 라벨: bug, dataset, performance, examples, training, stale
- 반응: 👍 2
주장한 문제: 에피소드를 하나의 .mp4로 concat할 때, 나중 에피소드에서 타임스탬프 경로 3개(parquet, video PTS, 누적 from_timestamp)가 어긋나 FrameTimestampError가 날 수 있다는 내용.
멘테이너(pkooij, 2026-03-17): 조사 칭찬, PR·회귀 테스트 요청.
weedmo 후속(2026-03-18): 수정 PR lerobot-pr-3179 제출 (https://github.com/huggingface/lerobot/pull/3179).
Collaborator(CarolinePascal, 2026-06-23): 재현 실패. PR 테스트는 main에서도 통과. 일반 녹화 규모에서는 float 드리프트만으로 1프레임(0.0333s)까지 가기 어렵다고 봄. 재현되면 상세 공유 요청.
로컬 스냅샷: raw/2026-09-26-lerobot-3177/