Erfa / (Hack)space Video Setup

Live-Streaming and recording setups in CCC Erfas and Hackerspaces.
Recordings of these groups can be found on https://media.ccc.de/b/erfas

Ideas for your own Setup

A hard- and software collection that can be used entirely or in peaces for small to midsize events in hacker-spaces / erfas.
It should be aligned with the best practices worked out in the operation of c3voc but be a more cost efficient solution.
We will list here only components we tested / use our self. This doesn't mean you can't use other components, its just an blueprint.
It also should be modular that it can be tailored to the needs and budgets of user and already existing components can be integrated.

In the following we list the main building blocks an make some suggestions what could be used.

  • FullHD Video recording
  • Capture Audio ⇒ audio
    • Headset + hand mic
    • Audio mixer (optional)
  • Postprocessing support to publishing on media.ccc.de and optional other platforms ⇒ publishing
    • without fuse recording ⇒ tracker import recording worker
    • with full tracker stack ⇒ normal tracker chain

old page (ger)

There are numerous options for cameras depending on your budget. In most situations we recommend to feed you audio into the camera via XLR. This has two main advantages, one it that you audio will be in sync with the video all the time, the other is that you have a backup of audio and video on the SD card of your cam. Also using SDI to connect the camera to your video mixer is a much more stable and reliable solution than e.g. HDMI. Therefore the following points should be taken into concern when buying a cam.

  • Audio in (preferable XLR)
  • Video out (preferable SDI)
  • SD card recording (much cheaper than other solutions)
  • A wide-aperture lens (if you don't have a professional light setup)

In most cases this will lead you to semi- / professional cameras which can be expensive. It may be a good option to look for used ones. A entrance level cam is the JVC GY-HM200E which sadly has not the best lens but has a reasonable price. A much better lens can be found in many Panasonic cams like ag-ac-160-eej which you probably can buy second hand.

A list of cameras which are also suitable to some extend can be found in our Distributed Conference / Lecture Setup page.

In most situations a headset results in the best audio quality, especially with untrained speakers. As the speaker don't alternates the distance between mic and mouth this also makes it easier for the audio mixer operator. In our experience most speakers prefer a headset because it keeps there hands free.

For question from the audience and moderation purposes a hand mic is a useful addition to the headset.

Depending on the budget a audio mixer is a useful addition to the setup. Especially if audio from the presenter laptop should be included. If a camera without audio input is used, a mixer with build-in sound card can be very useful. Our recommendation is to feed the output of the mixer (or of the two mic's) into the camera, preferable via XLR).

If it is in the budget, digital mixers can be a good addition to the setups. For references what is used by us have a look at Audio case.

A machine that is capable of running a software video mixer, encode the results for recording and streaming and that has capture devices is the central point of the setup. In our setup we run voctomix on it, Open Broadcast Studio (OBS) is another alternative. We recommend to run Linux here but if you into pain windows could work for to with obs.

Capture cards can be either PCIe based or USB 2/3 depending on budget and use case. We use mostly blackmagic decklink BMD DeckLink capture cards. A (probably not complete) list of alternatives can be found here Framegrabber / Scaler . Grabbing the camera input is usualy straid forward, capturing slides from speaker notebooks can be quite challenging. E.g. Apple Computer tend to believe the presentation belongs to Apple so they encrypt the output, also you will run into hackers with there hand tailored graphic stack which output 1337×42 and you need to somehow scale that. Here are devices that can do scalling, or grabber cards that are agnostic regarding the input a good option.

VOC CDN can be used by all erfas/friends just ask us :-)
we can either pull a “voc default mkv” from an icecast running at your side or offer an RTMP endpoint. Both ways the stream will end up in our cdn and you can use our Streaming website as a front-end. The preferred way is to just send us an pull request with your configuration. This also also you to embed the stream in your own webpage.

Depending on how much of our stack you use we have different option on ingesting you content in our publishing pipeline. The c3tracker can support you from cutting the raw videos to publish numerous formats to voctoweb (the software behind media.ccc.de) and other platforms like youtube. We can ingest ready produced videos with pre and postrole or let the tracker add those to the file.

  • erfavoc.txt
  • Last modified: 2020/10/29 10:57
  • by derpeter