Ypb — A playback for YouTube live streams

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Rewind to past moments in live streams and play or download excerpts

Ypb is a playback tool for YouTube live streams written in Go. It provides MPEG-DASH access to past moments in live streams, allowing you to rewind beyond the web player's limits, play selected excerpts instantly in any compatible player, or download them as local files.

Features

• Standalone CLI and proxy streaming server for playback
• Rewind precisely to past moments far beyond the web player’s limits
• Play excerpts without downloading via a built-in web player
• Capture a single frame or a timelapse of frames
• Works with any MPEG-DASH compatible player or downloader
• Uses yt-dlp to reliably fetch info and download media

Overview

sequenceDiagram
    autonumber
    participant D as Download
    participant E as yt-dlp<br/>(extractor)
    participant P as Proxy
    participant Y as YouTube
    D->>D: Generate MPD<br/>(proxied based URLs)
    D->>E: Pass MPD
    loop Download
        E->>P: Request segment (proxied URL)
        P->>Y: Request segment
        Y-->>P: Stream segment
        P-->>E: Stream segment
    end
    E->>E: Write to file

Loading

Dowloading stream excerpts with yt-dlp's general extractor

Ypb is built around MPEG-DASH to access past moments in YouTube live streams. A playback proxy wraps format base URLs so media can be streamed with error retry handling, and is used to generate manifests for the exact excerpts requested. Behind the scenes, yt-dlp handles video metadata fetching and JavaScript challenges.

The generated manifests can be fed to a built-in dash.js player for rewinding and watching in the browser (the play command), or passed to any other MPEG-DASH compatible player or downloader. Ypb also composes static manifests to saving excerpts to local files using yt-dlp's general extractor (the download command).

See Overview for details.

Installation

Ypb works on Linux, macOS, and Windows.

Read the Installation guide for different ways to install and run ypb.

Showcase

Download stream excerpts

Download the latest 30 seconds from a live stream:

$ ypb download --interval 30s/now Mm_zVDDUeNA && ls
Live-and-Just-Hatched-Royal_Mm_zVDDUeNA_20260102T102030+00_30s.mp4

Or download a 30-second excerpt starting at a particular time:

$ ypb download --interval '2026-01-02T10:00+00/30s' Mm_zVDDUeNA && ls
Live-and-Just-Hatched-Royal_Mm_zVDDUeNA_20260102T100000+00_30s.mp4

Play in the browser

Start the web player:

ypb play Mm_zVDDUeNA

Open http://localhost:9000 to play the live content, or edit the path parameter to rewind to a particular time:

http://localhost:9000/2026-01-02T12:00

Serve stream excerpts

Start the playback server to enable rewind requests:

ypb serve Mm_zVDDUeNA

With the server running on the default port 9000, you can preview excerpts with your favorite player, or with ffplay:

ffplay -autoexit -protocol_whitelist file,http,https,tcp,tls \
  http://localhost:9000/mpd/10m--now

Or download them with yt-dlp directly:

yt-dlp http://localhost:9000/mpd/10m--now

Images & artifacts

• ghcr.io/xymaxim/ypb: main container image with yt-dlp and ffmpeg installed
• ghcr.io/xymaxim/ypb-compose: compose file with ypb image plus PO token provider sidecar
• ghcr.io/xymaxim/ypb-mock: generates fixture media for mock playback, without hitting YouTube. See containers/ypb-mock for usage.

License

GNU General Public License v3.0.