5/24/2012 7:02 AM
The AVDELAY 3G
from Crystal Vision has been designed to deal with large lip-sync problems on incoming 3Gb/s, HD or SD signals containing up to four groups of embedded audio. With up to ten seconds of independently adjustable video and audio delay available, it can be used to correct big timing differences between the video and audio paths. AVDELAY 3G is a unique one-board solution that replaces separate audio and video delays, making it both more cost-effective and easier to control.
The need for a product like AVDELAY 3G has increased in recent years. Lip-sync has always been a common problem – traditionally one or two video frames of timing difference, but now there are increasingly situations where there can be multiple seconds timing difference between the audio and video. This has been caused by broadcast engineers looking for innovative ways to get signals from one side of the world to the other, which results in them sending the video and audio signals back to base by different methods – such as satellite, Skype and ISDN.
AVDELAY 3G’s maximum video delay will change depending on the video standard, with ten seconds available in SD, five seconds in HD and two seconds in 3Gb/s. Up to ten seconds of audio delay is always available. By featuring both audio and video delay, AVDELAY 3G can cope with the lip-sync being out in either direction – for example, if the audio is earlier than the video, the audio can be delayed to let the video catch up.
Explained Crystal Vision’s Managing Director, Philip Scofield: “We were asked to design AVDELAY 3G by a large news organization who knew of our video delays, but could not locate a product that met the needs of anyone receiving signals where the audio could be several seconds ahead or behind the video. With AVDELAY 3G they were able to accept feeds which would otherwise be difficult to view. We have since discovered many other installations who want to correct lip-sync errors that have been created in a variety of ways.”
AVDELAY 3G has been designed with maximum flexibility when it comes to setting the various delays. The video delay is adjustable in seconds and frames. The audio delay is adjustable in seconds, video frames and milliseconds. The video and audio will jump instantly to the new delay setting, allowing lip-sync errors to be rapidly corrected. The delays can be set to 0, 5 or 10 seconds by default, providing a useful starting point for making further adjustments.
Dealing with the embedded audio is particularly flexible: there are four separate audio delay processors and each can have its own delay timing – providing a total of four different audio delays at the same time, ideal for those with a number of audio tracks coming in via different mechanisms such as Skype and ISDN. AVDELAY 3G provides sophisticated handling of Dolby E audio, which is automatically aligned with the guardband of the outgoing video.
AVDELAY 3G joins Crystal Vision’s other recent product releases in its ability to be given integrated fiber input/output connectivity, allowing the signals to be carried over longer distances. Designed for SMPTE 297-2006 short-haul applications, the FIP fiber input option is used to receive an optical input and the FOP fiber output option to transmit an optical output using a Class I laser.
AVDELAY 3G saves broadcasters rack space by being a 4 x 10.5 inches module which fits in the standard Crystal Vision frames – available in 4RU, 2RU, 1RU and desk top box sizes – and with up to 12 boards fitting in 2RU.
It is used with the RM62 frame rear module to access the inputs and outputs, while the flexible control options include board edge switches, an active front panel on the frame, a remote control panel, GPIs, SNMP and the Statesman PC software. 21 video and audio alarms are available to flag up faulty signals, with the status indications including input video missing, audio missing, audio silence and Dolby E presence.
AVDELAY 3G is shipping now.
Based at Whittlesford near Cambridge in the UK and with an office in the USA, Crystal Vision provides digital keyers, picture storage modules and a full range of interface equipment including converters, synchronizers, distribution amplifiers and audio embedders to the professional broadcasting industry worldwide.