AV-over-IP: Simplifying Audio Breakout?

By David Meyer posted 11-16-2017 23:20


AV-over-IP runners

AV-over-IP has been a hot topic this year, and will only continue to grow next year. The balance between video performance, latency and network speed have converged enough to make it truly compelling. Oh, and did I mention cost?

The challenge we still have is that all solutions are proprietary. Some brands even have multiple proprietary solutions in their product mix which may not be compatible with each other. So unlike HDMI, which is a standard whereby products and brands can intermix and work (most of the time), AV-over-IP requires choosing a proprietary solution, which as a system can then connect through a home network.

SMPTE (The Society of Motion Picture and Television Engineers) only a few months ago released a new standard called SMPTE ST 2110. In discussion, they made a really good point that video and audio are typically multiplexed (eg; through HDMI), meaning they’re combined into a single stream. So if you want to get to either one, you have to receive the whole stream and decode it to get to the part you want; audio &/or video.

Sound familiar? Think audio breakout.  

Because IP is inherently a multiplex standard, SMPTE ask “Why are we carrying multiplexes inside of multiplexes?” Good question. Intended for professional production workflows, the new ST 2110 standard enables video and audio to be transmitted and routed separately, and where they need to go together can be synchronized with a time code. Can we have this in the resi space too…? Please?

Add to this the fact that some VERY smart people over at ISO are working on defining JPEG-XS as a new open standard as a big upgrade from JPEG 2000. I think this will be transformative, allowing economical and fast transmission of 4K60 HDR content over a 1GbE network, or 8K over 10GbE. The last advice I received from them was that they’re expecting to have the new standard ratified by mid 2018, so watch this space.

In the meantime we may not have industry-wide standards to enable the mixing and matching of different AV-over-IP products, but don’t let that put you off. Do your research. It’s worth it.

The nice thing about standards is that you have so many to choose from

                                                                         - Andrew S. Tanenbaum




11-21-2017 22:20

Absolutely @Evan Christensen​, that was a great podcast, and definitely recommended listening. Mr Heiss is the master!

We've been watching the developments in IP for some time, and as Mike said, hard switching is cumbersome and expensive. The multicast distribution approach of IP is so much more versatile.  

Compression is the key. It's a necessity not only for network speed management but also for file sizes. At the content creation level, a raw 10-bit UHD/30 capture produces around 7.5Gbps (nearly 1GB/sec). That's approx 1TB in just 18 minutes!

11-21-2017 14:07

Great thoughts.  Michael Heiss addresses something similar on this cedia tech counsel podcast episode.  He added that a lot of the content creators are now using HD over IP (in lieu of HDBT), which is another signal that there's a change coming down the pike for our industry.