Difference between revisions of "EMFBC"

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''Or how to jump the gun by 6 months, and not check for permission first''
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==WTF?==
 +
The aim of the game is to broadcast everything, and be awesome at it. We can expect to broadcast 2 stages live in HD, with graphics. And record clean versions for editing down to stick online later (but not 2 years later!) - like a few hours after the talk has ended. We also expect to be able to do act as an overflow facility - if one stage is full, we can send the video to another stage's A/V system. And for legal reasons, we'll also be able to not broadcast some talks, but instead broadcast a holding slide / other pre-recorded content. Overnight, we'll show a mix of recorded content, EMF on time delay, and possibly have guests in for chats. Essentially, we're aiming for the full works.
  
 +
== System overview==
 +
* We run it all video control/mixing from one location, possibly a caravan, possibly a tent. In there, we house the transmission control, edit PC's, record/playout servers, and push content from here too. It'll be full of screens & generate plenty of warmth!
  
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== Eh What? ==
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* We put a 'stagebox' in each track tent, and run fibre/coax (distance dependant)  to & from it to the master control room for video & audio. Each stage box will have a small hdmi router, a vision mixer, and some video convertors to take whatever people throw at it - SDI/VGA/DVI/composite from speakers laptops. Each box also outputs to the stage's projector, independently of mixing the broadcast feed. Audio is also taken into the stagebox from the track tent's sound desk. The stagebox will have connections for cameras as well (obviously!) The box will output the clean feed back to master control for broadcast(or not broadcast)/moderation/editing/overflow... Stageboxes will also act as an endpoint for comms, and be controlled remotely.
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Well, A few of us at London Hackspace have been thinking about how we could make the video side of things better. Much better.
 
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We theorize (with past examples in Student TV and Real world TV, that we can reasonably expect to provide:
 
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* HD Live streams for two stages
 
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* Overflow capacity (i.e. "Ahh, stage A is full, can we get the pictures & sound to stage B?")
 
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* All talks, Q&A sessions available on demand within 2 hours of their finish.
 
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* Overnight continuity (i.e. at the end of the day, play out content from previous EMF's, and with permission, content from popular hacky content creators)
 
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* A Cheesy closedown clock, a la BBC style 1am goodnight, hacking forecast, and national anthem.
 
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* Live graphics on the live streams (i.e. ''Jonty - Beeeeeeees", and perhaps the odd bit of moderated twitter integration).
 
  
 +
* If people want to provide pre-built content, we'll take it. Anything we can legally broadcast, with science.
  
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== Isn't this a bit early to start planning? ==
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* If people want to provide other live content, even mini-OB's over skype or other transport stream from inside the camp or another camp/conference, as long as there's an out-of-band comms channel.
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*No. Finding a good workflow takes time.
 
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*No. Although the cost of making HDTV has dropped massively, we still need to make our own bits (like controllers, not the mixers!!!) to keep costs down: Oddly, the controllers are the most expensive bit on hardware!
 
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*No. We need a while to source everything, and test kit together. Not to mention we'll be running a full test of the Master control room system beforehand.
 
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*No. Much of this planning cannot be done in a multi-threaded fashion.
 
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*No. EMF may not have even picked a site yet, but much of the infrastructure for EMFBC will remain the same. Pretty much the only thing that'll change is cable / fibre lengths, and that doesn't affect us until later in the process.
 
  
 +
* If people want to take content live, awesome. We'll give HD/SD-SDI or HDMI. Taking the transport streams may be possible too.
  
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== Can I bikeshed this? ==
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* If people want files out of us, we'll probably end up providing h.264 & PCM at 48k in an mpeg type container - as that'll likely be the way we send content to video hosting sites. If people want something else, then they can transcode it - we're looking at 20-50Mbps, so the result will still be decent after a heavy transcode.
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* Not quite yet. Bikeshedding will be available later on, for things like controller design, software for automation, gfx control...
 
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* Chat with us, we'll usually be talking about making TV.  
 
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* Yes, if your question is along the lines of "I clean up messy wikis, can I namespace this to my heart's content?"
 
  
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== Topology ==
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==Acquire these things!==
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===Considerations ===
 
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*Although undecided yet, EMF will likely have 2 or 3 stages, each probably 100 meters or more apart.
 
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*This means we need quite a bit of cable - at these lengths, we have a few issues: at 1.485Gbps (our baud rate) and 100m, we need some pretty hefty coax. This is kind-of-expensive. It begins to be cheaper to go down the fibre route...
 
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*Shorter = cheaper.
 
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*The connection to EMF-NOC will be easy - Cat5e/6 is cheap, and will already be everywhere on the camp.
 
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*HD Encoding and decoding devices will eat up too much space on the network (the cheap ones we could afford effectively packet storm a network, and we'd need a few!)
 
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*Capture (PC), encode > IP> decode (PC) is hilariously unreliable (we need zero failures at all), and introduces far too much latency.
 
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*SO, we are left with only direct connectivity as an option.
 
  
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=== Physical topology ===
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Compute resources:
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*We clearly need to sit our master control room (MCR) next to one of the stages - if our two stages are 100m each side of NOC, we can do a fibre run from MCR at stage A (STA), past NOC (middle), on to stage B (STB). This'll be cheaper than having MCR at NOC, and doing two fibre runs out to STA & STB. To get network, we simply attach at wherever MCR is, and then as EMF will have a lot of bandwidth, we don't need to worry about where we stream content from!
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*Switch. Managed, Gigabit. Or just multiple dumb Gigabit boxes.
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*If we have three stages, we'll pop MCR in the middle one (if there is a middle one), or at NOC if there is no clear shorter way of doing the runs...
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*Control PC
 +
**Reads the schedule, controls the videoservers, possibly controls the remote mixers.
 +
*Edit PC
 +
**Reasonable fast machine to run a video editing program on.
 +
**We'll cut down the chaff from the goings on in the stages, add Titles, Credits & end boards on this.
 +
**We'll upload our content from here too (in the background whilst we edit).
 +
*Storage / record machine
 +
**2TB that can do 200Mb/s. No other purpose.
 +
**Must be something like R10,R51,R60. Basically, quick, reliable.
 +
**Everything apart from the edit scratch disks will be here, so it needs to be nippy!
 +
**posibbly dual NIC (decide later).
 +
**Record the incoming feeds, and clip them at the start (set the clip name) & end(finish file).
  
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=== MCR or MCV or MCC ? ===
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*Videoserver(s)
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We need a home. The LHS Bikeshed has already proven that caravans are brilliantly cheap housing for electronics - cheaper than a van, and more prepared than turning up with a pile of stuff. I propose we take this example, and make the Master Control Room a Master Control Caravan. We can then take all the caravan bits out, put our hardware and custom (cheap) controllers in, pre rig everything, and just hook up on site.
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**Runs Graphics (fill & key) during the day.
 +
**Runs videos in the overnight continuity service. Can internally key the graphics for overnight.
 +
**This can be one machine per stage/stream, or combined.
 +
 
 +
*Streamer1
 +
**Streams the 1st Stream
 +
*Streamer2
 +
**Streams the 2nd Stream
 +
 
 +
 
 +
On the hardware side:
 +
*Screens (all HDMI 16:9 unless otherwise stated)
 +
**VideoServer Output 1
 +
**VideoServer Output 2
 +
**Multiview A
 +
**Multiview B
 +
**Program A
 +
**Program B
 +
**Edit Left
 +
**Edit Right
 +
**PC1 (optional, any)
 +
**PC2 (optional, any)
 +
 
 +
 
 +
 
 +
*HDSDI-HDMI convertors (LKV-368 are £30 on amazon/ebay)
 +
** 6 minimum.
 +
** for each stream: playout, multiviewer, program.
 +
 
 +
*Clocks (optional)
 +
**Leitch 1 (big hands clock)
 +
**LED1 (caravan left/front)
 +
**LED2 (caravan right/back)
 +
 
 +
 
 +
General items
 +
*Rack1
 +
*Rack2
 +
*MDU's
 +
*USB Keyboards
 +
*USB Mice
 +
*Phone charger :P
 +
*Network cables
 +
*2 Floodlights
 +
 
 +
 
 +
Outstation items (for each outstation)
 +
* Mini rack/flightcase
 +
* HDMI to HD-SDI convertor
 +
* VGA to HDMI
 +
* HDMI matrix
 +
* Power strip
 +
* 4 20M XLR cables
 +
* video mixer
 +
* ADC (audio)
 +
* Fibre TX/RX set

Latest revision as of 18:41, 5 February 2014

WTF?

The aim of the game is to broadcast everything, and be awesome at it. We can expect to broadcast 2 stages live in HD, with graphics. And record clean versions for editing down to stick online later (but not 2 years later!) - like a few hours after the talk has ended. We also expect to be able to do act as an overflow facility - if one stage is full, we can send the video to another stage's A/V system. And for legal reasons, we'll also be able to not broadcast some talks, but instead broadcast a holding slide / other pre-recorded content. Overnight, we'll show a mix of recorded content, EMF on time delay, and possibly have guests in for chats. Essentially, we're aiming for the full works.

System overview

  • We run it all video control/mixing from one location, possibly a caravan, possibly a tent. In there, we house the transmission control, edit PC's, record/playout servers, and push content from here too. It'll be full of screens & generate plenty of warmth!
  • We put a 'stagebox' in each track tent, and run fibre/coax (distance dependant) to & from it to the master control room for video & audio. Each stage box will have a small hdmi router, a vision mixer, and some video convertors to take whatever people throw at it - SDI/VGA/DVI/composite from speakers laptops. Each box also outputs to the stage's projector, independently of mixing the broadcast feed. Audio is also taken into the stagebox from the track tent's sound desk. The stagebox will have connections for cameras as well (obviously!) The box will output the clean feed back to master control for broadcast(or not broadcast)/moderation/editing/overflow... Stageboxes will also act as an endpoint for comms, and be controlled remotely.
  • If people want to provide pre-built content, we'll take it. Anything we can legally broadcast, with science.
  • If people want to provide other live content, even mini-OB's over skype or other transport stream from inside the camp or another camp/conference, as long as there's an out-of-band comms channel.
  • If people want to take content live, awesome. We'll give HD/SD-SDI or HDMI. Taking the transport streams may be possible too.
  • If people want files out of us, we'll probably end up providing h.264 & PCM at 48k in an mpeg type container - as that'll likely be the way we send content to video hosting sites. If people want something else, then they can transcode it - we're looking at 20-50Mbps, so the result will still be decent after a heavy transcode.

Acquire these things!

Compute resources:

  • Switch. Managed, Gigabit. Or just multiple dumb Gigabit boxes.
  • Control PC
    • Reads the schedule, controls the videoservers, possibly controls the remote mixers.
  • Edit PC
    • Reasonable fast machine to run a video editing program on.
    • We'll cut down the chaff from the goings on in the stages, add Titles, Credits & end boards on this.
    • We'll upload our content from here too (in the background whilst we edit).
  • Storage / record machine
    • 2TB that can do 200Mb/s. No other purpose.
    • Must be something like R10,R51,R60. Basically, quick, reliable.
    • Everything apart from the edit scratch disks will be here, so it needs to be nippy!
    • posibbly dual NIC (decide later).
    • Record the incoming feeds, and clip them at the start (set the clip name) & end(finish file).
  • Videoserver(s)
    • Runs Graphics (fill & key) during the day.
    • Runs videos in the overnight continuity service. Can internally key the graphics for overnight.
    • This can be one machine per stage/stream, or combined.
  • Streamer1
    • Streams the 1st Stream
  • Streamer2
    • Streams the 2nd Stream


On the hardware side:

  • Screens (all HDMI 16:9 unless otherwise stated)
    • VideoServer Output 1
    • VideoServer Output 2
    • Multiview A
    • Multiview B
    • Program A
    • Program B
    • Edit Left
    • Edit Right
    • PC1 (optional, any)
    • PC2 (optional, any)


  • HDSDI-HDMI convertors (LKV-368 are £30 on amazon/ebay)
    • 6 minimum.
    • for each stream: playout, multiviewer, program.
  • Clocks (optional)
    • Leitch 1 (big hands clock)
    • LED1 (caravan left/front)
    • LED2 (caravan right/back)


General items

  • Rack1
  • Rack2
  • MDU's
  • USB Keyboards
  • USB Mice
  • Phone charger :P
  • Network cables
  • 2 Floodlights


Outstation items (for each outstation)

  • Mini rack/flightcase
  • HDMI to HD-SDI convertor
  • VGA to HDMI
  • HDMI matrix
  • Power strip
  • 4 20M XLR cables
  • video mixer
  • ADC (audio)
  • Fibre TX/RX set
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