Will TR-03 Stay In Sync?

Last week the Video Services Forum released its draft recommendation for “elementary stream” IP media (read that as non-embeded audio). While touted by some as a low latency, low payload transport protocol with video, audio, and ancillary data being transported separately, I think it once again opens the Pandora’s Box of “out of sync” audio and video. I know that Thomas Edwards of Fox Networks said: “…when every packet is time stamped accurately, we should have better synchronization between media streams than SDI solutions could provide.” I thought that audio & video packets in MPEG-2 transport streams were time stamped as well, but that hasn’t prevented them from becoming annoyingly out of sync.

I say if you have to implement IP transport now, plan to use SMPTE ST 2022-6. (‘Cause it’s nice when audio and video arrive together.) And let’s see what actually happens when someone else actually implements TR-03 in a control room near you.

Must SDI Die?

… or can it just retire in Florida? Recent moves by SMPTE to standardize IEEE-1588 for timing and sync may help the move to an IP-based plant. And the Joint Task Force for Networked Media is studying best practices for audio and video switching. Al Kovalick has written a comprehensive article titled SMPTE Looks at All-IT Media Facilities on page 26 of the December 18th, 2013 issue of TV Technology. He discusses some of the papers presented at SMPTE’s Annual Technical Conference in October 2013 and how they can make an all-IT based facility possible in the near future.

[With no apologies to Cinegy. SDI is not dead yet and neither am I.]

UPDATE – Feb. 2016: Mr. Kovalick updates us on PTP with “Time Transfer in Networked Systems”.

(Note to me: SMPTE 2059-1 and -2 are SMPTE’s version of IEEE-1588 V2 – PTP)