English Premier League 2021/22 Season

[Jim McLean's Ghost]

1 minute ago, The Master said:

The technology makes that impossible. The line can only be extended to the level of the pitch. 

You he see that he’s leaning. That will put your shoulder further forward than your knee. 

You know they can draw the line to pretty much where ever they want. It is a picture, the pitch is not a physical barrier..

There is line that shows Kane onside. It has about the same amount of accuracy as the one that called him off. Why do they even pretend they can call offside to the level of precision they do. It was a close call, go with the decision on the park.

[The Master]

Just now, Jim McLean's Ghost said:

You know they can draw the line to pretty much where ever they want. It is a picture, the pitch is not a physical barrier..

VAR for offside is more than just a picture. It uses a 3D model of the pitch constructed using Hawk Eye. 

If there was no mechanism to stop the vertical lines at pitch level, VAR would be pretty much useless. 

Just now, Jim McLean's Ghost said:

There is line that shows Kane onside. It has about the same amount of accuracy as the one that called him off. Why do they even pretend they can call offside to the level of precision they do. It was a close call, go with the decision on the park.

Your line doesn’t account for parallax, nor can you categorically say that it’s directly below his shirt sleeve.

VAR does and can respectively.

[craigkillie]

There are far too many moving parts to be able to make offside calls as exactly as they pretend to. Even deciding when to stop the frame basically boils down to a guess.

[Jim McLean's Ghost]

1 minute ago, The Master said:

VAR for offside is more than just a picture. It uses a 3D model of the pitch constructed using Hawk Eye. 

If there was no mechanism to stop the vertical lines at pitch level, VAR would be pretty much useless. 

Your line doesn’t account for parallax, nor can you categorically say that it’s directly below his shirt sleeve.

VAR does and can respectively.

VAR doesn't account for parallax since it is done with one camera with one lens.

Yes there is no mechanism to stop vertical lines at pitch level then it is useless. Players's feet are obviously stopped at pitch level but trying to draw lines from an arm or a knee is just guessing.

[The Naitch]

That's a superb clearing header from Walker-Peters.

[Bully Wee Villa]

Kane should be suspended anyway.

[The Master]

Just now, Jim McLean's Ghost said:

VAR doesn't account for parallax since it is done with one camera with one lens.

No it’s not. 

It uses a calibrated 3D model of the pitch which absolutely does account for parallax. 

Just now, Jim McLean's Ghost said:

Yes there is no mechanism to stop vertical lines at pitch level then it is useless. Players's feet are obviously stopped at pitch level but trying to draw lines from an arm or a knee is just guessing.

You really should just give up now. 

The VAR drawing the lines doesn’t just fire up Paint and start scribbling. It’s all based on a calibrated model of the pitch which allows them to draw accurate parallel lines, and accurately determine where an “off ground feature” is relative to the ground. 

[Jim McLean's Ghost]

Just now, The Master said:

 

It uses a calibrated 3D model of the pitch which absolutely does account for parallax. 

Does it have a 3D model of the players? No. so it doesn't account for parallax for anything above the pitch

[The Master]

3 minutes ago, Jim McLean's Ghost said:

Does it have a 3D model of the players? No. so it doesn't account for parallax for anything above the pitch

It doesn’t need a 3D model of the players. The relevant feature is essentially a single point placed in the 3D space, which is then used to draw the relevant line. 

Edited December 28, 2021 by The Master

[Jacky1990]

12 minutes ago, The Master said:

VAR for offside is more than just a picture. It uses a 3D model of the pitch constructed using Hawk Eye. 

You sure about that? First Ive ever heard about 3D imaging and use of Hawk Eye.

Is it not just a replay with the screen paused on the frame they think the balls been played?

[The Master]

1 minute ago, Jacky1990 said:

You sure about that? First Ive ever heard about 3D imaging and use of Hawk Eye.

Is it not just a replay with the screen paused on the frame they think the balls been played?

It’s explained here - https://www.premierleague.com/news/1488423

[DrewDon]

Referee showing himself up as very anti-fun by blowing the whistle for full-time as Southampton were about to go through there. 

[The Naitch]

Well deserved point for Southampton. Spurs, even with the extra man, were largely hopeless in that 2nd half.

[Jim McLean's Ghost]

2 minutes ago, The Master said:

It doesn’t need a 3D model of the players. The relevant feature is essentially a single point placed in the 3D space, which is then used to draw the relevant line. 

Without a 3D model how does it determine where an arm or knee is in 3D space? You can draw a line down from anywhere and have it intersect at a tangent at any point you want. The VAR ref is the one who decides where a body part would intersect with the pitch. It is a guess.

[oneteaminglasgow]

VAR offsides may well be a nonsense based on guesswork, but this time it’ll have upset Harry Kane so we can chalk it up as a win. 

[Jim McLean's Ghost]

6 minutes ago, The Master said:

It’s explained here - https://www.premierleague.com/news/1488423

Hawkeye is only used to calibrate the cameras so they are all shooting frames at the same time. And the frame data is synced so that you can check 2 different camera angles on the same frame.

There is no 3D or multi camera use to decide an offside like the one today.

 

[The Master]

Just now, Jim McLean's Ghost said:

Without a 3D model how does it determine where an arm or knee is in 3D space?

By drawing a line from it that intersects with a known point in the 3D space. 

This is fairly simple geometry. 

Just now, Jim McLean's Ghost said:

You can draw a line down from anywhere and have it intersect at a tangent at any point you want.

The VAR technology prevents this from happening. 

The vertical line is drawn parallel to the y-axis. The pitch level line is generated based on where that vertical line intersects the horizontal plane (the pitch). 

Just now, Jim McLean's Ghost said:

The VAR ref is the one who decides where a body part would intersect with the pitch. It is a guess.

It’s not, no matter how many times you repeat it. 

[The Master]

8 minutes ago, Jim McLean's Ghost said:

Hawkeye is only used to calibrate the cameras so they are all shooting frames at the same time. And the frame data is synced so that you can check 2 different camera angles on the same frame.

There is no 3D or multi camera use to decide an offside like the one today.

 

Quote

Before the season, the pitches are calibrated by Hawk-Eye, creating a 3D model of each of them, which is then maintained during the matches.

 

[Jim McLean's Ghost]

Creating a 3D plane of the pitch (i.e so that the riduculous camber at Old Trafford is accounted for) is not determining exactly where Kane's body part is in 3D space.

 

[The Master]

1 minute ago, Jim McLean's Ghost said:

Creating a 3D plane of the pitch (i.e so that the riduculous camber at Old Trafford is accounted for) is not determining exactly where Kane's body part is in 3D space.

 

You don’t need a 3D model to determine where any point on Kane’s body is when placed inside an existing 3D model. 

As I said, this is simple geometry. 

Edited December 28, 2021 by The Master