OOAK Table Tennis Forum

The video challenge system was tested in world cup, and receiver a lot of love. Many cameras but easy to operate. Any toughts?

Don't know.. will have to go watch a few games first. I always thought line calls and such were not as much of a problem in table tennis as they are in tennis. I wonder if they actually show the whole challenge process in the abbreviated "highlights" videos we see on YouTube.

Iskandar

I wonder if that will include challenging hidden serves ...

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Retriever (sometimes golden, but often leaden)
Moderator, Inverted Retriever Technique sub-forum - http://ooakforum.com/viewforum.php?f=74

Then it'd have to go beyond that "Hawkeye" system they use in tennis. Simply setting up 3-4 cameras on each player for the umpire to review (or for an assistant umpire to watch in real time during serves) would go a long way towards addressing this, making it automated would be a great deal more difficult though doable.

Iskandar

EFFICIENCY BELOW ANY EXPECTATION.

ITTF VCR complex of 10-cameras did prove of little avail.. A lot of money gone waste. a lot of efforts gone,, Camera's optycs, can never determine the "net cord balls" should the such come out in play..
Lawn Tennis, they now using piezo-sensors instead.

Net-cord balls are easy. All you need is a little microphone. Who needs cameras for that? Same with edge balls - just mike the table. Telling an edge ball from a side ball shouldn't be too difficult, either, based on sound.

Who uses VCRs anymore???? I can imagine ITTF folks lugging boxes of blank VHS tapes....

Lawn Tennis still uses Hawkeye, last I watched..

Iskandar

?

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Retriever (sometimes golden, but often leaden)
Moderator, Inverted Retriever Technique sub-forum - http://ooakforum.com/viewforum.php?f=74

https://en.wikipedia.org/wiki/Hawk-Eye

Apparently it's based on cameras, computers, triangulation and computing the projected path of the ball. It's useful in tennis, but for table tennis I'd think miking the table and putting sensors on the net would be far more reliable for "line calls". Cameras paired with something like this WOULD be useful to determine serve visibility (apparently, in Cricket, they use Hawk-Eye to determine LBWs so it's capable of determining relative positions of the ball - and ball path - and player body parts) and non-vertical hand tosses.

Iskandar

Copying from the ITTF web site:




So I as a receiver cannot request TTR for a "false service", ie hidden serve by my opponent that has not been called by the umpire, but a server can request TTR if they have had a "false service" ie hidden serve called against them by the umpire, at least initially.

Also (not quoted but on the web site) there is a limit of 2 unsuccessful TTR calls per player per match. That seems to be a little low compared to say tennis which from memory gets 3 per set with an additional one in tie breaks.

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Retriever (sometimes golden, but often leaden)
Moderator, Inverted Retriever Technique sub-forum - http://ooakforum.com/viewforum.php?f=74

Note that the umpire can call faults on the service without the player issuing a challenge. And it seems the system flags things like non-vertical ball throws automatically, so the umpire's attention will be called to it when it happens. I think player challenges would be for "line calls" and net cord balls.

EmRatThich posted a video about this today:



Iskandar

Brave Russian woman with iron guts. A good fellow of mine.

Very interesting! The ball was clearly obstructed from the camera angle, but the camera was not right behind the receiver, so it's not actually conclusive.

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Yeah, Russian officials tend to be brave with iron guts.. Probably too much so. Wonder if the Olympics ban applies to officials as well as athletes.

Iskandar

https://www.newstube.ru/media/nastolnyj ... ident-ittf

ITTF has always been a good friend with Russia.
ITTF needs money badly. Russia is a superior money donator.
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