Detect SDI record flag on BM Arduino shield?

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Detect SDI record flag on BM Arduino shield?

PostMon Mar 25, 2019 11:02 pm

Hi all,

(nerdy) DP here from film and drama. I'm building a video cart to support various on-set tasks including playback. I've got a nice thing going with various routers, recorders etc.

What I'm trying to do now is automate recording based on the state of the 'record flag' that's included in the ancillary data on the incoming SDI line from the camera. In our case we're using ARRI Alexas. We have a bunch of devices on set (namely Teradek wireless receivers and Sound Devices PIX records that another department use) that correctly pick up the record flag from the Alexas so they record when the camera itself is recording.
However the Blackmagic Hyperdeck Mini I'm using doesn't support the Arri standard of record flag (BM support tell me it only supports the Panasonic standard), and even if it did I am often feeding it a quad split view of various cameras, the SDI feed of which doesn't have any such data set.

What I'd like to do is find some sort of box that would take an SDI signal loop through and detect the record flag and allow some sort of relay/switch/RS-422/ethernet or whatever signal to be activated as a result. Then I can get those on every incoming camera feed and create some sort of logic whereby if ANY of the incoming cameras is recording, then start the recording of the quad split.

So far it seems there is basically nothing around that does this... I was wondering if the BM SDI Arduino shield might present a way to access this ancillary data - but will it allow me to detect the ARRI standard?

Obviously I can just press the record button myself but I'm sure fellow posters here can appreciate the desire to automate this :)

Any thoughts or ideas greatly appreciated.
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Re: Detect SDI record flag on BM Arduino shield?

PostTue Mar 26, 2019 10:05 am

The BMD shield has no option for that.

I might have some solution.. But depends.. Do you have any info in which ANC data that rec flag is hidden? :)
I have some hardware now that also has the ability to pull timecode from the SDI signal up to a 3G-sdi signal.
Daniel Wittenaar .:: Xtreemtec Media Productions ::. -= =-
4K OBV Trailer, ATEM TVS HD, 4M/E Broadcast Studio 4K, Constelation 8K, Hyperdeck Studio 12G, Ursa Broadcast 4K, 4K fiber converters with Sony Control

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