Tuesday, 22 September 2026

Virtual Finish Line: How Sony and HBS built a new data‑driven view of sprint finishes

SVG Europe

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World Athletics’ new Virtual Finish Line (VFL) system made its debut last week, offering host broadcaster HBS a near‑real‑time 3D reconstruction of the final metres of sprint races. The project, developed by Sony’s Sports Entertainment Technology Development team, combines optical tracking, computer vision and rapid 3D rendering to give directors an additional visual option during live coverage.

At the heart of the system, shown exclusively to SVG Europe ahead of the event, a 26‑camera optical‑tracking array installed at gantry height around the track. Each PTZ unit is motorised, synchronised and network‑controlled, forming a continuous capture line around the stadium. “From those cameras, we capture the video, and we also capture the motion from video analysis. With this motion data, we create the visualisation,” explained Sony engineer Koshino Sota, who oversaw the camera deployment.

The cameras feed into a Sony OB hub, where captured video and motion vectors are aggregated and converted into 3DCG. HBS receives the generated graphics in its OB truck, where directors can choose to integrate the VFL output into replays or analysis sequences.

The system is designed to feel like having “1,000 cameras everywhere,” Sota said — giving directors multiple angles and perspectives that would be impossible to achieve with physical cameras alone.

A new workflow for track and field

Hiro Hattori, General Manager of Technology for Sony’s Sports Entertainment Technology Development team, described the R&D project as a departure from traditional athletics coverage.

“This is a brand‑new approach for track and field. So that’s why my R&D team is involved,” he said. “The focus is on finish‑line reconstruction of sprint races, where margins are smallest and outcomes are decided in milliseconds. We want to create 3D visualisation footage for broadcasting, to help fans understand all of the drama.

“Our system captures every motion on the track, mainly around the finish area. Soon after capturing such motion live, we generate the 3D visualisation for the broadcasting system.”

Development and technical challenges

The proof of concept premiered in Budapest is the result of 18 months R&D and further discussions with World Athletics during the Tokyo Championships last September. Additional behind closed doors tests were then made in Japan. Sony already had experience with optical capture for football officiating, but adapting it to track required new engineering.

“We had two main challenges,” Hattori explained. “We needed to capture data with absolute precision. Even if the difference of distance [between athletes] is very, very small, it matters.”

The second challenge was to process the VFL output quickly enough to be made available like a replay.  “If we create this kind of footage one day after the event there is no value. But there is tremendous value if we can compress the workflow,” he said.

“Our motion capture is almost live. Within one second we can capture the motion data. After that we integrate the official timing data from Seiko and then create the visualisation.”

Currently this takes less than 30 seconds and the aim is to reduce that further.

The graphic visualisation workflow was developed jointly with HBS. “This part was mainly based on discussions with HBS, because they are professionals of sports broadcasting and also of fan engagement,” Hattori said.

Stefan Koch, senior director at HBS, described the process as a genuine co‑development effort with Sony and World Athletics. “It’s definitely a joint venture,” he said. “We sat together before World Championships Tokyo and asked what could we do, or what would make sense? And then we came together to this idea.”

For Koch, the appeal of the VFL was simply that the finish is the defining moment of a race, yet traditionally one of the hardest to show clearly.

“The winner of the 100m is the athlete whose chest cross the line first. That is the rule.  If you think about it, this actually means a virtual wall. Now, for the first time, we can actually show this virtual wall in reality,” he said. “What is the most important moment on track? It is that moment. Now we visualise that.”

Koch sees it as a way to give viewers a clearer, more intuitive understanding of what happened. “This is a visualisation, a new ‘aha’ moment. Seeing this, fans can understand the result and the performance so much better. If it’s a tight finish, we will always show the official Photo Finish because you want to see what the judges saw.”

HBS worked with Sony to define the angles and replay patterns directors could use. Two main options emerged: a single camera move from front to diagonal to top, or a sequence of three angles showing the finish from different perspectives. Koch said the choice depends on the race format: “In the semi‑finals, the single camera move works best because we have four [qualifying] athletes to cover. For the Ultimate Champion — the visualisation could work better by showing just their performance from three angles because it’s always about who wins.”

Camera control and presets

The camera array is fully remote‑controlled. “Each one has a motorised head, so we can control it from our video village,” Sota explained. Sony prepared multiple preset angle patterns — multi‑camera sweeps or single‑camera arcs — which HBS directors can select per race.

“We show the director a couple of examples - shorter versions, long versions, multi‑camera and single‑camera. Then they pick, for every race, what they want for the broadcast. It gives them a lot of flexibility.”

However the number of cameras trained on the athletes is less important than their angle. Most of the cameras in Budapest were positioned towards the finish line, since this is the focus of the first application though in theory an entire circuit of a race could be tracked and data-captured for CG visualisation.

“It’s important for the cameras to have line of sight onto the athletes on the track,” Sota said.

It’s also not yet practical to create 3D visualisations of races like the 1500m where athletes will bunch together onto a single lane – partly because the data gathering of movement from individuals would be obscured, partly because the on-screen presentation could look confusing. In addition, many longer duration races tend to be more strung out with a clear winner so there’s less of a compelling case for 3D storytelling at the finish line.

The motion‑capture pipeline uses computer vision and AI, trained on general human movement rather than athletics‑specific datasets. 

“For this Championship, we are just showing one kind of visualisation. Soon— maybe after the next Ultimate Championship — we will add more. You can overlay more data. You can extract more data. It will expand to another discipline,” Hattori said.

Sony also hopes to migrate parts of the processing pipeline from GPU-powered workstations into the camera itself, creating a more compact edge‑processing platform.

The next staging post for the tech could be September 2027 when the World Athletics Championships returns to Beijing 12 years on from the city’s successful staging of athletics’ flagship event and almost two decades on from the Beijing Olympic Games.

Sony is an official global partner of the World Athletics Ultimate Championship and is also providing Hawk-Eye’s video replay service for officiating.


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