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Low latency for perfect timing every time

Customers tell us that knowing the video delay before measuring for lip sync makes the processes of identifying the core reason for lip sync errors, easier and more effective.  

Low latency is essential to keep a broadcast “truly live” - nobody wants to hear about the winning goal on social media or via a text before they’ve seen it yet on television! Imagine watching a golf tournament with graphics that show the trajectory of the ball. These graphics can take up to a second to generate and if this latency is overcompensated for, you may see the flight of the ball before the golfer hits it! 

If left unmeasured, latency can creep in via several routes - frequently accidental. For example, inherited settings from the last event, or pieces of equipment in the chain that are not actually required, using cameras in multiple locations or that generate various levels of delay, etc. 

Live interviews between a studio presenter and a remote correspondent require low latency links for a true two-way interactive conversation - audiences dislike long pauses waiting for replies. Many major broadcasters pay considerable amounts for low latency links between the studio and key locations to avoid this issue, but it may not be necessary. MatchBox Latency can objectively measure the speed of links, thereby saving time and money if the existing infrastructure has sufficiently low latency already. 

With MatchBox, determining offsets takes just a matter of seconds, saving valuable engineering time. It is fast, easy to use and accurate, simplifying the task of measuring delay and delivering a lip-sync reading as well. The system launches a timed test pattern as the source with a bespoke analyser receiving and decoding it at the destination resulting in the timing measurement. This method can be thought of as a multi-meter for signal timing with a probe at each end of the section of interest. 

Using MatchBox, production teams can ascertain how many frames of delay are generated on a particular path; identify whether the uplink speed is fast enough for a two-way interview; ensure that the timing for graphic overlays and sports commentary are spot on; and line up the timing on cameras from different locations. In the case of the latter, this capability ensures that when watching any sport that involves action moving around a track that viewers don’t see replication – in other words, the same runner, car, or cyclist arriving at the same point twice. 

Lip-sync and latency measurement with Hitomi MatchBox

The test pattern can originate from either MatchBox Generator or using an iOS device held in front of the camera running our free Hitomi Glass app.  A licence is required for the analyser to decode the latency signal but not to send it. Hitomi has made it possible to turn on the QR code with the generator to send a time stamp out and this is free at the point of 'generation'.  

Much is talked about the need for “low latency”, but it is rarely quantified, now it can be. MatchBox is already deployed worldwide with major name broadcasters so widespread adoption of this new technology can be rapid.   

MatchBox Latency brings certainty and scientific measurement to an aspect of broadcasting which can be subjective and hard to prove by human eye and ear alone. 

- Russell Johnson, Director of Hitomi Broadcast

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