FizziQ : Video Analysis for Physics
A mobile phone app to analyse video.
VAR in football
What is offside - Video Training Test 1
Below is the first of two training videos that will help you develop your skill and to identify what is and what is not offside call. This first video tests 25 situations and asks you to identify what is the correct call. After you have taken the 1st test and further developed your weariness, then why not take the next test.
PRO assistant referee offside test - 2015
Test your offside judgment with this PRO assistant referee video, featuring 25 examples from an AR training camp.
Are you good enough to be an assistant referee?
Sunday League Each level has 5 videos to watch. After each clip, decide whether the player is onside or offside. You will only have five seconds to answer.
Document
(PDF) Errors in judging 'offside' in football
By analysing video of 320 Dutch professional-league situations, the authors show that assistant referees are mis-aligned with the second-last defender in 21 % of cases and, when that happens, make systematic errors that average ≈1 m in the direction predicted by the optical-error hypothesis.
How AI Detects Offside |Semi-automated Offside Technology|
Why it's difficult for referees to be accurate with offside and how VAR works.
Video analysis using Kinovea software - presented by - Djalel ARAB-
How to markup footballer positions using Kinovea app to help decide if offside
(PDF) Interpretation and application of the offside law by expert assistant referees: Perception of spatial positions in complex dynamic events on and off the field
Paper to determine (1) whether the flash-lag effect emerges in offside situations on the field of play or off the field when presented as computer animations or as video footage of real-life matches; (2) to examine offside decision-making errors in two standards of assistant referee – international FIFA and Belgian national referees
Motion signals deflect relative positions of moving objects
Research paper describing effect
Flash-lag Effect: Visual Illusion 3D
The flash lag illusion or flash-lag effect is a visual illusion wherein a flash and a moving object that appear in the same location are perceived to be displaced from one another
Flash-lag Illusion - The Illusions Index
A demonstration of the flash-lag effect (FLE) - a visual illusion where a moving object and a flashed (stationary) object, which are physically aligned at the same location, appear to be misaligned. The moving object is perceived as being ahead of the flash, even though they are spatially coincident at the moment of the flash.
You are the linesman
Explains how the Flash Lag effect makes it difficult to judge offside.
How offsides are determined by VAR
In the Premier League, offsides are determined by the VAR using Hawk-Eye’s virtual offside line technology. This has two levels. Gridline - A two-dimensional line, which can be quickly positioned in line with the final defender for clear offside decisions. Crosshair - These are two lines that are positioned for the defender and attacker.
VAR: I used motion capture technology to show why the Premier League gets tight offside decisions wrong
VAR: I used motion capture technology to show why the Premier League gets tight offside decisions wrong
Scientists explain why VAR is so controversial in football
Just 132 milliseconds may explain why offside decisions given in football by video assistant referees have proven so controversial, according to scientists. Academics used motion capture technology to assess the accuracy of video assistant referees (VAR) and suggested a reason for why football struggles with offside decisions.
A offside solution needn't be very VAR away: Premier League bid to change controversial line system| All Football
Motion capture reveals why VAR in football struggles with offside decisions
New research by the University of Bath has used motion capture technology to assess the accuracy of Video Assistant Referee (VAR) technologies in football. The study suggests that VAR is useful for preventing obvious mistakes but is currently not precise enough to give accurate judgements every time.
VAR in Football: Enhancing Fairness or Disrupting the Game?
Video Assistant Referee (VAR) was introduced to football with the aim of enhancing the fairness and accuracy of officiating decisions. While it promises improved precision, it has sparked a heated debate: Is VAR killing the game of football? This article delves into the benefits and criticisms of VAR, its impact on the sport, and the potential ways to improve it.
OPINION: Tech said Sterling was 2.4cm offside but allowed 13cm margin for error| All Football
Evaluation of Factors Influencing Assistant Referee Decisions in Determining "Offside" in Football | Slobozhanskyi Herald of Science and Sport
Law 11 - Offside | IFAB
Official FIFA rules for offside
Real Time Offside Detection using a Single Camera in Soccer
A significant breakthrough in soccer officiating is the Video Assistant Referee (VAR) system, leveraging a network of 20-30 cameras within stadiums to minimize human errors. VAR's operational scope typically encompasses 10-30 cameras, ensuring high decision accuracy but at a substantial cost. This report proposes an innovative approach to offside detection using a single camera, such as the broadcasting camera, to mitigate expenses associated with sophisticated technological setups.
A Step to VAR: The Vision Science of Offside Calls by Video Assistant Referees - George Mather, 2020
Evidence in vision science points toward two problems with the application of the offside law in VAR, due to their use of a live TV video feed in reviews. First, due to physical and perceptual limits on spatial resolution, there is a significant probability that the spatial positions of the ball and players as judged by VAR will be several centimetres to one side of their true positions. Second, the 50 Hz TV update rate means that judgements of the time-of-contact between player and ball will on average be 10 ms too late, which translates into an increased likelihood of offside calls in fast-moving play.