Sports technology has moved from the background into the way spectators understand competition. Football is the clearest example. VAR has made video-assisted officiating familiar to fans, while semi-automated offside technology brings multi-camera tracking, player positioning and ball-contact timing into the decision-making process.

Under the IFAB VAR protocol, the video assistant referee may assist only in the event of a clear and obvious error or a serious missed incident. Its review areas include goals, penalties, direct red cards and mistaken identity. FIFA describes semi-automated offside technology as a support tool intended to make offside decisions faster, more reproducible and more accurate.

Judo has developed more quietly, but high-level international judo has also entered the video-assisted era. IJF Sport and Organisation Rules state that a certified Video Replay System is mandatory for IJF-sanctioned competitions. Video replay is therefore part of modern competition structure, not merely an optional extra.

The challenge is different from football. Judo involves body-to-body contact, balance breaking, control, landing angles, continuous action, counters and transitions into ne-waza. The difference between ippon, waza-ari and no score can depend on the relationship between several movements rather than a single line or frame.

The next step is unlikely to be an AI system that automatically awards ippon. A more realistic direction is deeper video analysis: identifying phases of a contest, analysing posture and transitions, organising key moments and helping coaches, referees, athletes and spectators understand a match more efficiently. A 2024 study has explored automatic extraction and analysis of judo combat phases from streamed tournament footage.

Technology may not replace referees, but it is changing how people understand contests, review technique and learn judo.

Sources: IFAB, FIFA, International Judo Federation and arXiv

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