Blackmagic Forum

Hello everyone, I have a question, I have a setup of 8 Ursa Broadcast in an auditorium, and an Atem constellation 4ME.

I need something to do training with the cutting team, but I didn't want to do it live, but rather after recording.

The idea is to record the event with 8 cameras and then play it back on atem to train the team. I need a cheaper solution, as buying 8 hyperdeck recorders now would be expensive.

Initially my idea was to use the Decklink Quad 2, which has 8 inputs/outputs. and switch when necessary.

I saw some software for recording, but I couldn't find one that plays back later, would anyone have any tips?

vMix with the Instant Replay can do 8 channels record - not sure about playing back all at the same time. You'll need really fast storage to do this on a single machine though, FYI.

And computer with high lanes to cpu

I had this exact same need recently where I needed to be able to train new volunteers on the switcher, but that's a mission critical task that can't really be trained (hands on) during a live worship service. Training during practice times are not optimal for us since the band, singers, etc aren't in the same positions as they are during the service. I set out to find a way to ISO record and playback all inputs, so training can be on "real" services.

In my scenario, I need to record and replay eight inputs in sync (5 cameras, 1 graphics, 2 lower third fill+key).

Our switcher standard is 1080p29.97, so I devised a plan that leverages packing four inputs as separate quadrants in a single 2160p29.97 video. This results in far less videos that I have to sync, and reduces the hardware to the minimum (at least that I've been able to devise...).

The hardware chain that I am using leverages Teranex Mini converters and HyperDeck Studio Minis. Why the older HyperDeck Studio Mini? Because it does 2160p in the 1/3 rack space, so a single rack shelf can hold Teranex(mux)+HyperDeck(rec/play)+Teranex(demux) for a full record/playback chain.

The record chain for four inputs looks like this:

Four inputs (4x 1080p29.97) -> Teranex Mini Quad SDI to 12G-SDI (mux into quadrants) -> HyperDeck Studio Mini (2160p29.97)

The playback chain starts with the same HyperDeck:

HyperDeck Studio Mini (2160p29.97) -> Teranex Mini 12G-SDI to Quad SDI (demux from quadrants) -> Four outputs (4x 1080p29.97)

I've prototyped this as a proof of concept with a computer playing a 2160p video with four cameras in the quadrants into the 12G->Quad3G demux. It worked perfectly.

I've just acquired the rest of the hardware to add the HyperDecks and add channels 5-8. In theory, this is scalable higher in groups of 4 channels with the HyperDecks sync'd for both record and playback.

The HyperDecks can in theory be replaced with a computer for the record/playback as long as you have the ability to play the videos back in sync. I don't know of any affordable software that can easily playback sync channels like this, though.

Hope this helps! Please let me know if you find any other options.

Yes this is interesting idea ..

I installed the gear and tested it tonight. I'm pleased to report that it works for replaying a multicam service for training on the switcher.

Some notes to keep in mind:

- The Quad SDI to 12G SDI will only mux 4to1 if all four signal inputs are present. If any one of the four drops, the Teranex will fall back to only passing through one of the signals (rather than 3 and an empty quadrant). This is something that makes sense, but I had not anticipated. I expect I can easily work around a missing input by providing Black, Bars, or duplicating another signal (I'm feeding it from a Videohub, so remapping inputs is easy).

- These HyperDecks only support ProRes or DNxHR for 2160p, so the file sizes will be larger than if we could use H.264.

I need to do further experimentation with the two HyperDecks to see if I can have a single button to trigger record on both, as well as a single button to trigger sync'd playback on both. I also need to configure some macros on my Streamdeck to quickly swap inputs 1-8 from live to training replay and back. I'll start recording services this weekend to further prove the concept.

BlkKnight : Better than VIDEOHUB is use AUXes on ATEM .. if any input fail , then atem is sending BlACK , but video is not interupted ..

If U want to sync recording of multiple hyperdecks , try this .. I was never tested it :

https://hyperdeckpanel.com/

Thanks for the suggestion. I currently have an ATEM 2 M/E Production Studio 4K with a measly 6 aux outs, which are all currently in use. Maybe one day I'll have the Constellation 4K and those 24 aux outs.

I'll take a look at hyperdeckpanel. I'm also going to test configuring a few buttons on my StreamDeck to manage the HyperDecks.

yes on streamdeck U can manage to send START record to multiple hyperdecks to ONE button .. So it may work too ..

Ensure the recordings have the same timecode and sync’d playback is simple.

FWIW I don’t think the mux process will work a bunch of random SDI sources or even camera’s that aren’t genlocked. Likely the mux would need to be fed by the aux bus to ensure correct signal timing. Optionally use a 4x1 multiview instead of the 3g/12g for the mux.

Good Luck