Recording on location

Most articles about the latest developments in outside broadcasting tend to focus on the production truck, the mobile control room. But today, particularly for sports broadcasting, much of the real action takes place inside the truck parked next to it. This is where every feed is recorded, multiple replays are lined up after each critical piece of action, and highlights are cut together with frightening speed.

We call this the VT truck, even though it may not have many — or even any — videotape recorders inside. But it is a convenient enough expression.

Not so long ago, an outside broadcast truck only needed four or five VTRs, which could be easily accommodated inside the scanner. Even today there are jobs that can be accommodated without a dedicated VT truck. For major music events, where quality is the top consideration, we tend to fit as many VTRs into the scanner as are needed; 18 or 20 HDCAM decks is not uncommon.

But today's sports applications require a great deal more flexibility and speed of response. For that reason, we build dedicated VT trucks.

Slow-motion cameras

To provide coverage of an English Premier League football match in HD, and in particular at a feature match, two production trucks are needed — one for the match and one for presentation.

Linking them will be the VT truck, which is likely to have as many as 50 incoming feeds. This includes the various cuts and clean feeds from each truck as well as ISO camera feeds. Adding to the total will be a number of super slo-mo cameras that, from the CCU, are effectively three feeds to the server.

Other sports have different requirements, including more super slo-mo cameras; a big occasion like an international athletics meeting, for example, might use six or more. There is also a growing interest in high-speed cameras for extreme slow motion that need their own dedicated server and processor, which again is installed in and operated from the VT truck.

Various sports have different requirements in terms of replays, and broadcasters and production companies will have a diverse approach. Some use a standard formula for replays of key action; others are more flexible, perhaps because of the time available.

For the recent Twenty20 world cricket championships, there were 28 cameras at each ground, including super slo-mo and stump cams (miniature cameras mounted inside the stumps themselves). Despite the relatively frenetic pace of Twenty20 cricket, there is still time to reflect on wickets falling, and each dismissal is illustrated by a different combination of replays.

Router requirements

On one level, the VT truck is actually a simple concept. It needs a lot of production server capacity, plus monitoring to match the available server channels. And it requires a big router.

There are multiple demands on the router. Inputs tend to be fixed for each event, but outputs are dynamic. The director in the scanner will want replays on just a few buttons. There will be perhaps four replay feeds from the VT truck. Each replay sequence will be sorted first using the VT truck router so the director has no surprises in taking them in order.

With the assumption that all big sporting events are now covered in HD, the audio is likely to be in 5.1 surround. That adds to the size and complexity of the router, again taking up space in the machine room.

Along with video and audio, there is a need for IT connections, with one or more gigabit Ethernet networks installed. These allow for fast transfer of content between servers and editing systems.

Truck ergonomics

The key to making the complicated technology of the VT truck work lies in the ergonomics. In particular, excellent communications are required between the operators in order to deliver multiple replays quickly and accurately. Specifically, this means good eye lines between the assistant director managing the truck and the individual operators.

One solution is to create a single-sided expansion to give room for the operators looking at a long monitor wall. The expansion could contain in excess of 150 individual screens, either discrete monitors, or multiviewers. (See Figure 1.)

The monitor layout needs relatively little flexibility, because it is a logical layout of input and output feeds for each server channel. The most important consideration is for the operator to have a good, clear view of each channel, wherever he or she happens to be sitting.

The layout of where operators sit is an important part of the flexibility of the unit. Again, this depends on the requirements of the sport, the production company and the broadcaster. Sometimes an operator will look after multiple replay channels; on other occasions, an operator may be dedicated to a single super slo-mo camera.

The operators will each have a clear idea of what they have when a key piece of action occurs. Because they work closely with the assistant director (AD) or VT coordinator, they can communicate clearly whether they have something good enough for air and cue the replays. The AD will then tell the director in the scanner what is available and that it is ready to roll. The design of the truck goes a long way to making all that happen within just a few seconds.

Resolving disputes

Another important recent development is the increasing use of television coverage by match officials. At the top level, both rugby and cricket, for example, have dedicated officials supporting the on-pitch referee or umpire with difficult decisions.

These television match officials need to see replays from multiple angles, and often a frame either way is critical in their decisions. Was a fielder touching both the ball and the boundary rope at the same instant? Did a player ground the ball behind the try line before or after hitting the corner flag?

With a bit of training, the official can use his or her own slow-motion controller to jog through a sequence one frame at a time, if necessary. But again, communication is vital. The VT truck has to cue all the relevant angles and offer them to wherever the official is sitting. In turn, the official needs to tell the scanner what the decision is so the right graphics sequence can be played to announce it to the television audience and the crowd via the giant screens on the ground.

Similarly, the television commentary team now includes an expert or two who will analyze key moments of play, or contrast the different styles of players, and use replays to illustrate their point. Sometimes they draw on the replays or highlight players using a telestrator.

Providing for the commentator

One of the first expert commentaries was part of a feature developed by Channel 4 in the UK for its cricket coverage, called “The Analyst.” In this case, the expert actually sits in the VT truck, and a camera is rigged so that he or she (and the edit assistant) appear in vision to explain the points before going to the side-by-side replay comparisons.

Again, it gives the expert commentator greater control over his or her piece if the commentator has direct control over the replays, to run a remote controller to wherever they are, and have a means of switching between local and remote controllers. The replay is set up in the truck and is then run by the commentator.

In addition to instant replays, there is an expectation that highlights packages will be put together quickly. At half-time in football and rugby, and on the final whistle, viewers expect an immediate summary of the action. Cricket — particularly the big one-day events — now has quick updates on the action after power plays, at the fall of wickets and so on.

One solution is to create this as a sort of linear edit, using an edit controller connected to the server network. The alternative is to have a desktop editor sitting on the server network. The design of VT trucks can include a separate room for an editor, and another space can be set up in the truck's control room.

Again, flexibility is the key. Producers will employ different editors who will have their own preferences for NLE software. Finally, the VT truck may also be home to one or more graphics systems. These could include a character generator to add stings around replays and perhaps the graphics following a decision by a television match official or third umpire. There may be a requirement for a specialist graphics system, which could be operated from the VT truck.


In conclusion, the technology in a VT truck is well established — multiple servers, graphics and editing, all linked by a flexible routing infrastructure and good monitoring.

What makes the difference between success and disaster is 90 percent ergonomics. The operators are confined to the truck for long periods of intensive work — it could be eight hours or more during a cricket match — so it has to be comfortable as well as practical.

Eye lines are vital, not just for monitoring but to enable the immediate, almost instinctive communication that makes the whole replay system work swiftly and smoothly, so that audiences always see the angles they need to reinforce their love for the game.

Matthew Ivey is the sales and marketing director for NEP Visions.