Bilibili Danmaku Scraper

Extract decoded Bilibili (哔哩哔哩) danmaku (弹幕, "bullet comments" — the scrolling on-video reactions Bilibili is known for) with full timestamp, color, mode, and sender data, plus a per-video summary (unique senders, peak-activity minute, time range). No login required.

Why

Danmaku is returned by Bilibili's own API as raw Protobuf binary (x/v2/dm/web/seg.so), not JSON — most scrapers either skip it entirely or depend on a third-party protobuf library. This actor uses a hand-rolled varint/tag decoder (no dependency) against the community-documented DanmakuElem/DmSegMobileReply schema, ported from the mature sibling actor bilibili-all-in-one-api (already live and verified on Apify), along with its bvid -> cid video-info resolution.

Pricing differentiation: competing danmaku actors on Apify charge per comment on top of a per-video fee (e.g. $0.00999/video + $0.00015/danmaku, which adds up fast on a popular video with thousands of comments). This actor charges one flat price per video — you get every danmaku it finds, no matter how many, for one price.

How it works

1. Resolves each input video (URL or bare bvid) to Bilibili's internal cid (the video-part id danmaku is actually indexed by, not the bvid).
2. Fetches danmaku in ~6-minute segments (maxSegments input, default 3), stopping early once a segment comes back empty.
3. Decodes each segment's raw Protobuf into structured JSON: id, progressMs (position in the video), mode, fontSize, color, midHash (hashed sender id), content, ctime (send time), weight, pool, attr.
4. Pushes one dataset row per video: video metadata + a summary (unique senders, first/last send time, the single busiest minute and its count)
   • the full decoded danmaku array.

Input

Field	Type	Description
videos	array of strings	Bilibili video URLs or bare bvids (required)
maxSegments	integer	Max ~6-minute segments to fetch per video (default 3, max 20)

Output

One dataset item per video:

{
  "bvid": "BV1Q5tG6bEX3",
  "title": "...",
  "owner": "...",
  "duration": 123,
  "viewCount": 456789,
  "totalDanmakuCount": 18165,
  "fetchedDanmakuCount": 254,
  "summary": {
    "uniqueSenders": 249,
    "firstCtime": 1788404458,
    "lastCtime": 1788427409,
    "peakMinute": 0,
    "peakMinuteCount": 159
  },
  "danmaku": [
    { "id": 3203383280, "progressMs": 2067, "mode": 5, "fontSize": 25, "color": 16777215, "midHash": "432e7d85", "content": "是什么蒙蔽了我的双眼", "ctime": 1788404458, "weight": 11, "attr": 1048580 }
  ]
}

totalDanmakuCount is Bilibili's own reported count for the whole video; fetchedDanmakuCount is how many this run actually pulled (limited by maxSegments — raise it for very long videos).

A video that fails to resolve (bad URL/bvid, deleted video) doesn't abort the run — it's logged and pushed as an { input, error } row so a batch of mixed-quality input doesn't lose the videos that did work.

Pricing

Pay-per-event, one flat video event per successfully processed video — no per-comment charge. See the actor's Pricing tab on Apify Console for current tiered rates.

Getting started

$apify run