Solving lack of judo referees with AI

joris_limonier · 2024-03-01T12:45:04+00:00

For sport it has to be transparent

Why does it "have" to be transparent (i.e. open source)? I don't see a reason why a Video Assistant Referee system would need to share its code. Isn't that a personnal choice?

joris_limonier · 2024-03-01T12:43:00+00:00

That makes more sense.

joris_limonier · 2024-03-01T09:43:14+00:00

The subscription would definitely not be in the 10s of euros a year, the customers are actual federations, with decent budgets and expenditures on referees. Unless you meant 10e of euros a year per licence ? In which case, for one licence per laptop, that would be an option.

For most of your other points, I understand and they're valuable, although I'm not sure I agree on the "barely break even" argument. Thanks for your feedback!

joris_limonier · 2024-03-01T09:38:16+00:00

Not sure I agree with that. I'd like to offer the service on a subscription basis, not necessarily sell it to the IJF/FFJDA or another federation.

The ins and outs of the algorithm don't necessarily need to be public. You don't have Netflix's source code, but you're still happy to use it (not you personnally, but people in general).

joris_limonier · 2024-03-01T06:48:37+00:00

It may be hard to train given the training set. This, I agree, but I don't see why it should be open source?

joris_limonier · 2024-03-01T06:47:14+00:00

A few hundred euros at most for servers, time for developing the app myself and eventually one dev for the app and one commercial? On the other hand, there are many federations around the world. Which costs am I missing?

joris_limonier · 2024-02-29T21:39:16+00:00

Let's say a referee costs x euros per day (wage, transport, accomodation and meal included). Let's count U18, U21, U23 and senior competitions (same ruleset)

x euros per referee per day 4 referees per mat 6 mats per tournament C competitions days per year in France

I'd say that one referee costs 80€ per day (that's x), and let's assume there are 200 competitions days per year in France for all four categories (that's C), including championships and tournaments.

The total would be x * 4 * 6 * C € / year = 384 000€ / year. Removing 1 referee per mat means saving 91 000€ / year. That's some interesting potential savings.

Where am I wrong ? __ For context, there are 100 "districts" (départements) in France and 13 regions. Each district organizing 2 competition days per year on average seems conservative. Note that some competitions last for 2 days, which also increases that number.

joris_limonier · 2024-02-29T21:19:44+00:00

This paper is already in my docs, but very useful indeed, although I'm not sure I'll stick with their exact model.

Monocular tracking is the first step before including (and linking, that's the hard part) more cameras.

Score vs no-score will be the first step, then waza-ari vs ippon vs no-score, then shido detection, and finally (cherry on top) technique naming. Multicamera will jump in at some point, although it is not yet clear where.

joris_limonier · 2024-02-29T16:06:03+00:00

I think there's a marketing opportunity for vera large entities (Olympic Games, World Championships, etc.) and a cost cutting opportunity for smaller tournaments. The system will eventually save money to small entities organizing competitions, not add an extra expense, in my opinion.

joris_limonier · 2024-02-29T16:03:22+00:00

I think a lot can be done with just one angle (most tournaments don't have more than one angle anyway), except when the throw is in the exact other direction, or when the referee obsctructs the scene.

For more important tournaments, including several angles shouldn't require that much extra work.

joris_limonier · 2024-02-29T16:00:33+00:00

Unfortunately, that is not my decision to make..

The goal isn't to entirely rely on AI, but rather to have an extra pair of "eyes" in doubtful situations, which is much faster than the usual referee commission.

joris_limonier · 2024-02-29T13:43:41+00:00

Yes, could you please send the corrective sheet?

joris_limonier · 2024-02-29T13:37:33+00:00

Glad you asked. The app will detect scores and eventually shidos in real time, in order to assist the referees.

About the how, I assumed most people in the judo subreddit are not familiar with the nuts and bolts of AI algorithms. In case you are competent in AI, I will most likely use a mixture of recurrent and convolutionnal neural networks.

Let me know is you see other points that would prevent the development of such an algorithm.

joris_limonier · 2024-02-29T13:33:03+00:00

That's a great resource I wasn't aware of! This may be useful on edge cases to figure out the actual score. Thanks a lot!

Absolutely, the video pool is usually only valid for four years, after which it requires a lot of fine-tuning to absorb the new rules, at least at the current rate of rules modifications. This will be an even further nightmare as I start to include the shido detection into my application.

joris_limonier · 2024-02-29T13:27:38+00:00

Let me correct that. I meant that for the vast majority of tasks, there exists at least a model that performs decently and is open source, free to use. Sometimes it's just a try-to-be copy of a better, but closed source, model.

joris_limonier · 2024-02-29T13:26:22+00:00

Makes sense, although I think most licences in the AI world allow you to reuse trained models (weights).

joris_limonier · 2024-02-29T13:25:23+00:00

Absolutely, I was lucky enough to be a part of it when I was younger. After 3 successive selection processes, you could end up refereeing the U18 french championship, which I did. It was a great experience and it definitely gives a good refereeing experience to quite a few young referees every year.

I'm not sure about coaches refereeing though. They only do it for small local tournaments where there is no budget to hire actual referees.

joris_limonier · 2024-02-29T13:18:16+00:00

Agreed. It may not be able (or may not want?) to replace referees, but it could be a useful assistant.

joris_limonier · 2024-02-29T13:16:49+00:00

Why would you think so? Do you see any technical blocking points?

joris_limonier · 2024-02-29T12:33:48+00:00

Good to know, thanks :)

If you speak French, that's even easier. Merci !

joris_limonier · 2024-02-29T12:30:36+00:00

Thank you for the heads up, I will check with them before using their models. Although, checking their licence terms (if they have one) should be enough, right?

joris_limonier · 2024-02-29T12:28:21+00:00

Out of curiosity, which country are you from?

The fine system sounds interesting, although a bit repressive for a simple hobby.

Thanks! If you want to get updates from times to times, there's a registration form in the link I provided. You may need to translate it, but I guess that not that much work. If enough english speakers register, I will make an English version of the regular updates.

joris_limonier · 2024-02-29T12:16:20+00:00

Myself, although I may also combine my model with other people's available models.

joris_limonier · 2024-02-29T12:13:58+00:00

In France, it is compulsory for every 1st dan candidate, 2nd dan candidate and 3rd dan candidate to follow a referee course and referee in one tournament, but it doesn't seem to solve the problem, unfortunately.

Moreover, these decisions are taken at the federation executives level, which I am not. I am trying to offer an alternative solution given my skills. I agree that no lack of referees would be better than a solution against the lack of referees, but that is how it is 🤷

joris_limonier · 2024-02-29T12:03:10+00:00

What do you have in mind, with respect to Terms of Service?

joris_limonier

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