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.

MPEG Suspected In Lip Sync Errors

Deborah D. McAdams writes in in the March issue of Television Broadcast:

“Lip sync is notoriously bad in digital broadcast television, making a lot of content resemble the original English-dubbed Godzilla films….”

Interesting is the information appearing in the print but not the on-line version of the article: “…Others [individuals knowledgeable about the issue] point out that splitting audio and video from the get-go…was a bad idea in the first place.”

No, really? Embed that audio ! That’s my motto. I’ve seen too many ‘engineers’ running around like chickens without a head (sorry, poor choice of imagery) because they were sending analog audio through the plant with their HD-SDI video and wondering why it was out of sync.