Operation MySpace and Kulabyte Bring Live HD Flash to the Web
The baseband video was then sent from the de-multiplexer to the Kulabyte encoder via HD-SDI with embedded audio, the embedding being key to keeping the audio and video in sync for HD broadcast content. After the unicast stream was encoded with Kulabyte’s 2-pass variable bitrate (VBR) VP6 encoder, it was sent to Akamai for distribution to computers across the U.S.
"This was a great test for us," said Blake Wenzel, Co-Founder of Kulabyte. "On the encoding side, the part Kulabyte was responsible for, it ran flawlessly for 5 hours with audio/video sync."
The portion that I watched was in sync, and I checked back from time to time to see if it was working correctly on several machines, including a MacPro 8 Core, an iMac, and a Dell Dimension. The encoder also handled all the typical things that a concert throws at it: flashing, pulsating lights; lots of smoke; and shooting under low light conditions.
Others had some issues with the playback; Dan Rayburn noted on his blog that that sync and frame rate fluctuated during his viewing time.
"For the past 10 minutes, the video is really stuttering and the audio is a few seconds behind the video," wrote Rayburn, about 2.5 hours into the 4.5-hour broadcast. "The video has dropped to about 12 frames per second from the 30+ I was getting before. Moving down from the high to the medium stream is not solving the quality issues. Lots of stuttering and the low stream is doing 8.2 frames per second for me."
At one point during the webcast, the commercial satellite feed went down and Kulabyte had to switch to a feed that was upconverted from SD and sent from a military satellite. After the commercial satellite came back up, it took a few moments to sync the audio and video while Kulabyte made the switch. Still, all in all, the feat of getting a low-end HD stream via a live encode from one side of the country to the rest of the U.S. was a laudable accomplishement—and a good first start for live HD content.
"This is a big production end-to-end and proves that the web’s not that far behind the TV when it comes to quality," said Wenzel.
Soldiers and family members can also upload video messages for the troops in MySpace’s Vlog area, while others can call 818-641-1441 to leave an audio message for the troops.
Simultaneous viewers—a key metric for live streaming—had not been released as of the morning of March 11. The concert will be rebroadcast, on traditional cable television on FX at 11 pm Eastern on April 12.