Tuesday, July 01, 2014

Near synchronous video over UDP/IP with Sony's NXL-IP55

Just about the only things that caught my eye at the recent Beyond HD Masters day at Bafta was Sony's IP Live system. This is a single product called the NXL-IP55 which puts four 1080i 4:2:2 signals over a gigabit connection - so modest 6:1 compression with a well-defined single field of latency. The camera channels can go either way (so three source cameras and a return preview monitor for example) and embedded audio plus tally & camera head (colour) and lens control are included. It's quite expensive ($10k per end) but is the only video-over-IP device which I've seen so far which is suitable for live production.  



Kieran said...

Do you know what technology they're using - I assume some form of J2K?

Would be interesting to have a look inside.

Phil Crawley said...

Maybe, but Sony have a long history of brewing their own versions of compression; DigiBeta, although DCT-based looks nothing like MPEG2 (which was cutting edge in the early nineties). BetaSX uses a weird 2-frame GOP; I,B,I,B and HDCam was entirely closed (although, like Digi is DCT-derived).
I shall investigate further; I'm hoping to score a demo unit and when I do I'll let WireShark have a look at the packets and maybe there will be some indicator?

Kieran said...

What I have done in the past is basically look for the parts of the packet which look like noise. I then made a file out of this "noise" and ran it through ffmpeg to see if the heuristics could recognise any codec structure. It depends how complicated their framing is though.

That or there is maybe an ASIC on board that's easily identifiable like the Analog Devices J2K chip.

Kieran said...

I think this will explain what Sony are up to: