milmilOffline Downloads
Keep episodes, subtitles and danmaku on a Mac and play them with no server in reach.
Overview
The macOS client can copy a series onto the Mac it runs on and play it back without the server. The copy is not a second library — it is a cache of what you are about to watch, kept inside a disk budget you set, and it disappears again once you have watched it.
Offline downloads are a macOS client feature. The server's part is one endpoint that describes what a copy needs; the web app streams and does not keep local copies.
What a copy contains
Each episode is kept whole, so nothing has to be fetched at playback time:
| Part | Notes |
|---|---|
| Media file | The original file, byte for byte. No transcode, no remux. |
| External subtitles | Every sidecar track the server knows about, with its language and title. Embedded tracks come along inside the file. |
| Danmaku | A snapshot of the comment track as it stood when the copy was made. |
Keeping a series by hand
From a series page or the 離線 / Offline tab, choose the episodes to keep. Progress is shown per episode, downloads resume after a restart, and an episode can be pinned so the rules below never remove it.
Keeping episodes automatically
Automatic keeping is off by default — spending gigabytes without being asked is a surprise. Turn it on in Settings › 離線 and it will:
- Keep the next 1, 2, 3 or 5 unwatched episodes of every series you follow.
- Re-run on launch, once an hour, and whenever the server reports a new episode is ready.
- Drop a watched copy 24 hours after you last played it, unless it is pinned.
- Stay under the quota — 5, 10, 20, 50 or 100 GB — by removing the oldest watched copies first. Pinned copies are never removed.
Playback
A local copy sits at the top of the playback ladder:
- Offline copy — played from the Mac's own disk.
- Local file — the library file over a mounted volume.
- Direct stream — byte-range requests to the server.
- Remux — MKV repackaged as MP4.
- HLS transcode — adaptive streaming.
The player falls to the next rung when one is unavailable, so an offline copy that has been deleted behind the app's back simply streams instead.
Staying current
Every file in the manifest carries an ETag and a size. When the server's copy of a file changes — replaced by a better release, repaired after a bad download — the local copy no longer matches and is fetched again on the next rule run.
API
GET /api/v1/anime/{bangumiId}/offline-manifest returns every playable episode of a series with its file URL, size, ETag, container and codec, its subtitle tracks, and its danmaku URL — everything a client needs to make a copy in one call. See the API reference.