NBA tests Hawk-Eye for improved officiating


LAS VEGAS — The future of basketball officiating may lie in a broadcast trailer sitting in a parking lot in the baking hot Nevada desert. The unassuming exterior belies the (thankfully air-conditioned) interior, where Hawk-Eye has set up a couple of study rooms, adorned with desks, monitors, a referee-intercom system and more monitors.

On the right is the group overseeing the implementation of the Hawk-Eye player and ball tracking system, which is set to replace Second Spectrum as the raw data collector and improve the offering by providing 3D pose data via 29 points on the body instead of a single center of mass. To the left is the local replay room, a luxury not typically afforded in the NBA Summer League.

This fortnight on the UNLV campus is intended as an experiment in innovation, as the league conducts a final test of its new tracking provider while also evaluating new options for reviewing close calls and then communicating those decisions quickly to the earpiece or wristwatch of an on – court official.


“Number one is just a dry run of the core tracking system because it’s the lifeblood of the team’s front offices and Sportradar, our partner — we want to make sure it works because it’s the foundation of all of this,” said Tom of NBA Basketball Strategy. Ryan, who oversees technology initiatives. “On top of that, we get to see for the first time what a fully integrated tracking-plus-video-replay system looks like. We’ve never used tracking data live in a playback center.”

The legacy product from Sony-owned Hawk-Eye is its precision ball tracking used to judge line calls in tennis before expanding to track players, their limbs and balls in other sports, such as MLB. Its other primary offering is Synchronized Multi-Angle Replay Technology (SMART) video replay used by the NFL and others.

Now, the NBA is pairing the two with an eye toward generating supplemental evidence to help referees make goaltending decisions, the primary focus this year. Foot-on-the-line and last-touched-out-of-bounds calls will be in R&D throughout the year. In the future, these decisions could be fully automated, although that step would require sign-off from the Competition Committee and the National Basketball Referees Association.

“Our main goal here at Summer League is to show how all of our different technologies can come together to create this synergy of solutions to ultimately give the NBA what they need to better manage the game,” said Dan Cash, Hawk -Eye’s CEO for North America. “We believe that if you connect it [tracking] with replay, which we demonstrate here, you have a really powerful tool to be able to run the game effectively.”

Hawk-Eye installed its optical tracking system in all NBA arenas over the course of two months, January through March of this year. That brings 14 cameras with 4K resolution, expected to operate at 120 frames per second – double the broadcast standard for sports – and could go even higher, although the processing power required necessitates a trade-off with latency. A 15th camera can sometimes be installed, capable of a whopping 1,000 fps with even higher resolution.


What these cameras provide is, first of all, more angles of the action. A questionable three-pointer in the first few days of Summer League lacked a crucial broadcast view, but one of the Hawk-Eye cameras had a better angle to confirm the foot was behind the line.

But the tracking data provides a new dimension of analysis. The NBA flew out its usual Secaucus-based replay operators for a lawsuit. “It’s video plus data, which is a new skill to learn,” Ryan said, adding that “we have another [replay] partner that we are really happy about,” referring to EVS. Hawk-Eye’s three previous visits to the Summer League were all for background testing; it’s the first time it’s used in a game.

The cameras collect positional data about the basketball and the players’ hands and then apply the rules of goaltending and the laws of physics. On the replay operator’s screen are yes-no indicators for the goalkeeping criteria.

“Goalkeeping is relatively easy – if the ball passes its tip, if it’s over the cylinder, if it touches the backboard – those are all pretty defined use cases, but if we haven’t collected data for a significant amount of time, you don’t ‘don’t have a historical data set to reference to understand where your pain points are,’ said Hawk-Eye commercial director Justin Goltz.

“Realistically, the technology is moving at a pace so it can do it relatively quickly, but there’s a lot of logistics to get it from this broadcast truck or from the stadium down to the field that has to hash out over a season or two. “

The operator also sees a different screen experience with a replay animation similar in spirit to what Hawk-Eye has made famous in tennis. The NBA is still evaluating the best presentation of information and images to firstly help make the correct call and secondly show the fans. “A big part of this initiative is just more transparency,” Ryan said.

Following the same adage that content is king but distribution is queen, so too with this enhanced replay format accuracy is paramount but efficiency is also essential. The league is testing two methods of communication to its umpires: both audible messages to an earpiece or haptic and written transmissions to a clock.

The NBA, for example, introduced a new mechanism to relay a scoring change from the replay center to the on-court referees last year. If a two-pointer turned into a three, or vice versa, a blue light would flash at the scorer’s table. The problem: looking in that direction was never part of the usual routine or field of vision. Of about 120 such blue light indicators, only five were organically spotted.

It’s an obvious starting point — and not new, as other sports, such as soccer, have been doing this for years — but it could lead to other use cases.

“Live communication with the umpire is definitely a core component of our strategy because if we’re doing all this work on the automation side,” Ryan said, “you need to be able to communicate that with the umpire in real time.”

Leave a Comment