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Topics - bogieman

#1
Hawkeye may have to go to specsavers; error may be the full width of a post at HQ


The focus seems to be on the speed of the decision making to get the estimated information to the referee, but there are greater issues underlying.

The premiership uses more cameras for a smaller scoring area than the gaelic scoring area. The EPL systems has proven to better the FIFA margin-of-error requirement of +/- 30mm, that's 60mm; a sliothar just slightly larger than this, and goal posts are usually 90mm, the crossbar should be 125mm when round.
The cameras installed in croke are old technology now regarding resolution, frame-rate and imaging processing power, compared with the new premier league cameras, but the actual technical details are 'commercially sensitive' therefore private. The GAA has paid for this system, so know the installed accuracy, but have they specified the exact parameters for their specific set-up, or left that to the 'experts' ?

So underlying issue is accuracy; inclusive of the camera resolution, framerate, optical field of view, imaging processing including ball path extrapolation, camera frames synchronisation, speed of ball, target parameterisation of ball, post and crossbar diameter, how much of the ball can the cameras see, camera mounting vibration, parallax and triangulation errors, variable 'noise' like a keepers hand holding it or the ball travelling past the camera view of a white background in one or more cameras, like a white sign, or even a white post...

So what is seen on the hawkeye graphics is a statistical estimate of where the ball may be, without knowing the potential error, which would seem to be +/- a few centimeters or inches, old money. I wonder why the graphics do not show the error sphere around the ball ? Only then can an informed decision be made.

I'll leave aside the argument for who makes these decisions, there is enough debate in society regarding computers making decisions with their inherent incompetencies and abnormalities, ie self driving vehicles, finance control, medical consultation, military engagement, and hurling points.

Will the GAA provide their hawkeye calibration data (less the commercially sensitive information) for the system that can decide the result of an all Ireland in croke park ?
I'm not a betting man, but the probability, for voluntary publication, lets say, is 'nailed on'.

May have to investigate eagleye...


Ps not a one-off, but 2 consecutive matches