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| 1 | +--- |
| 2 | +title: "Video Streaming Project History" |
| 3 | +date: 2025-03-09T13:18:35+08:00 |
| 4 | +draft: true |
| 5 | +--- |
| 6 | + |
| 7 | +Over the years, PLUG has gone through multiple generations of its |
| 8 | +video recording/streaming system. |
| 9 | + |
| 10 | +## Version 1: DVswitch |
| 11 | + |
| 12 | +The first recording system was based on [DVswitch][DVswitch]. This was |
| 13 | +a client/server video mixing system: |
| 14 | + |
| 15 | +* Clients read DV video or audio sources, and send it over the network. |
| 16 | +* Server provides a UI allowing an editor to mix audio and video |
| 17 | + sources in real time to stream online or record to disk. |
| 18 | + |
| 19 | +Our video sources were: |
| 20 | + |
| 21 | + * [Canon Vixia HV30][Canon] DV camcorders. |
| 22 | + * [Canopus Twinpact 100][Twinpact] VGA capture device. Connected |
| 23 | + between presenter's laptop and projector to capture their slides. |
| 24 | + |
| 25 | +Both devices provided a DV video feed over Firewire, which could be |
| 26 | +captured by a laptop and sent over the network using |
| 27 | +`dvsource-firewire`. |
| 28 | + |
| 29 | +Microphone audio was routed via a small mixing board that appeared as |
| 30 | +a USB sound card, which was sent via `dvsource-alsa`. |
| 31 | + |
| 32 | +These would all feed in to DVswitch, which would produce an output |
| 33 | +stream that could be sent to an Icecast server for streaming and |
| 34 | +written to disk for later processing. |
| 35 | + |
| 36 | +[DVswitch]: https://web.archive.org/web/20180326132702/http://dvswitch.alioth.debian.org/wiki/ |
| 37 | +[Canon]: https://global.canon/en/c-museum/product/dhc738.html |
| 38 | +[Twinpact]: https://archive.org/details/manualzz-id-908869 |
| 39 | + |
| 40 | + |
| 41 | +## Version 2: BigBlueButton |
| 42 | + |
| 43 | +In 2020 during the COVID pandemic lockdowns, we started investigating |
| 44 | +ways of holding meetings remotely. One piece of software we considered |
| 45 | +was [BigBlueButton][BBB]: an Open Source web based video conferencing |
| 46 | +system with a focus on classroom style meetings with a single |
| 47 | +presenter talking to a large audience members. |
| 48 | + |
| 49 | +While we never ended up using BBB for fully remote meetings, it did |
| 50 | +offer a way to improve our ability to record in-person meetings: |
| 51 | + |
| 52 | +* Through the use of an HDMI capture device, we could make our |
| 53 | + existing cameras appear as USB webcams. |
| 54 | +* As the mixing board acts as a USB sound card, so behave similar to a |
| 55 | + headset. |
| 56 | +* The presenter could log in to BBB to show slides or screen share. |
| 57 | + |
| 58 | +We could then live stream the meeting to anyone not present in-person, |
| 59 | +and produce a recording. |
| 60 | + |
| 61 | +It also offered a few benefits over the old DVswitch system: |
| 62 | + |
| 63 | +* No dependence on Firewire: these expansion cards could be a bit |
| 64 | + unreliable and it was getting hard to source replacements. |
| 65 | +* We were no longer limited to standard definition video. |
| 66 | + |
| 67 | +One downside was that recordings live within the BigBlueButton |
| 68 | +instance. Rather than a single video, the slides, screen share, and |
| 69 | +webcam footage are all served separately and stitched together by a |
| 70 | +web app. This would be a problem if we ever wanted to move off of BBB. |
| 71 | + |
| 72 | +To solve this, we wrote [bbb-render][bbb-render]: some scripts to |
| 73 | +download the various files that make up a recording and assemble them |
| 74 | +into a [GStreamer Editing Services][GES] project. This could then |
| 75 | +render out a single video file suitable for archive and publication on |
| 76 | +YouTube. |
| 77 | + |
| 78 | +This also gave an opportunity to add some PLUG branding, in the form |
| 79 | +of opening and closing cards and a backdrop. |
| 80 | + |
| 81 | +[BBB]: https://bigbluebutton.org/ |
| 82 | +[bbb-render]: https://github.com/plugorgau/bbb-render |
| 83 | +[GES]: https://gstreamer.freedesktop.org/documentation/gst-editing-services/ |
| 84 | + |
| 85 | + |
| 86 | +## Version 3: OBS Studio? |
| 87 | + |
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