building VOC manual

Per building (A, H, K and U), you should be a team of at least three. Janson has a dedicated knowledgeable volunteer.

communication channels

  • fixed telephony

number

where

201

K NOC

202

K NOC

203

K NOC

204

K NOC

220

H2111

221

H2215

222

H1301

223

H1302

230

AW1125

240

Janson cam

250

K VOC

251

K experimental

260

U VOC (U4228)

261

UA2118

262

UB2252A

263

UB5132

264

UB5230

271

UD2120

272

UD2218

273

UD6125

300

infodesk K/dispatch

310

infodesk H

390

CI

For matrix channel invites, please ask VOC.

Your tasks before the conference:

  • (Friday) take the equipment to the rooms in your building

  • (Friday) work from the biggest to the smallest room

  • (Friday) do basic setup: cam, sound, plug in cables, basic audio checks with microphones, … See below for details.

  • (days of the conference) ensure the rooms are ready before the first talk starts

During the day, you have a fixed spot in your building:

Your job in your building, with the backup from VOC:

  • monitor video and update scene if necessary. See the “Monitoring and control of video streams” section for more details;

  • assist speakers and respond to problem reports in the building;

  • proactively fix problems with video. In some rooms, this includes preventatively replacing batteries!

monitoring and control

Monitoring should be available at https://control.video.fosdem.org. Request access from VOC or your per building video responsible.

  • https://control.video.fosdem.org/showbuilding.php: Main tool with video previews of camera, slides and mix streams, with sound levels. Shows all rooms, or a single building.

  • Grafana with audio levels of all audio mixer ports, for all rooms and selectable for a set of rooms

  • mpvwrap to examine a stream directly through its tcp:// link from the browser

  • scene selection for the video mix

  • (TBD) host-level monitoring for all involved infrastructure, to see network outages and such.

Access to https://control.video.fosdem.org is available from Friday until Sunday evening. Every per-building team should have a way to see the monitoring well enough, either via the in-room beamer or a large screen.

general overview

showbuilding.php looks like this:

#figure(image(“showbuilding.png”, width: 170mm))

On top, you can select the buildings to see.

For each room in the building, from top to bottom:

  • Room name. Its background is white if the sound levels are ok, red if there is no data, and yellow if the audio levels are not within the defined boundaries;

  • Snapshot of the camera input, updated every 2–3 seconds;

  • Snapshot of the slides/laptop input, updated every 2–3 seconds;

  • Snapshot of the mixed stream output from the video mixer, updated every 2–3 seconds. This is what gets sent to the viewers of the streams;

  • Graph of the levels of the sound. The blue line is the microphone input, the green-yellow is the room ambiance level picked from the camera internal microphone.

The three bands on the sound levels are, from top to bottom:

  • Yellow band, from 0 dBm to -14 dBm - peaking/too high;

  • Green band, from -14 dBm to -30 dBm - ok;

  • Red band, below -30 dBm - too quiet or missing;

The sound levels for the microphone input during a talk need to be in the middle (green) band. It’s good for the levels from the camera also to be in that band during a talk.

per-room control

The per-room control looks like this:

#figure(image(“control.video.png”, width: 170mm))

The “room status” on top is used to set if the room is either full or not. It’s mostly for use for the devroom managers.

The 4 buttons below control the video mix:

  • side-by-side presenter - picture in picture, large slides, small camera view. This is the default

  • side-by-side slides - picture in picture, large camera, small slides view.

  • fullscreen presenter - the camera view on full screen.

  • fullscreen slides - the slides view on full screen.

On the right side there is a preview of the current streams, same as in showbuilding.php above. Below that is a graph of the output levels, same as described above.

Below that there’s a link to a Grafana instance with all levels.

On the bottom left there is the audio mixer control. It’s split in two parts - input and output.

The inputs are the three inputs on the box, and PC is the analog input from the HDMI capture card (the sound channel split from it). It carries either the camera audio (for a cambox) or the presenter’s audio from their HDMI output (for the slides box).

The outputs are to the camera, to the room PA, and to the left/right channel of the headphone jack (for monitoring purposes).

For each slider, there’s the current setting and the level at the moment, that should be moving in almost-real-time.

At the inputs, below the sliders there’s a checkbox to select to which output channels the input channel gets sent.