Quantification of Impact of a Cricket Ball

The cricket is one of most popular games in the Asian subcontinent and its popularity is increasing every day. The issue of replacement of the cricket ball amidst the matches is always an uncomfortable situation for teams, umpires and even supporters. At present the basis of the replacement is solely on the judgement, experience and expertise of the umpires, which is subjective, controversial and debatable. In this paper, we have attempted a new approach to quantify the number of impacts or impact factor of a 4-piece leather ball used in the International one-day and test cricket matches. This gives a more objective and scientific basis/criteria for the replacement of the ball. Here, we have used a well known and widely used thermal infra-red (TIR) imaging to capture the dynamics of the thermal profile of the cricket ball, which has been heated for about 15 seconds. The idea behind this approach is the simple observation that an old ball (ball with a few impacts) has different thermal signature/profile compared to the that of a new ball. This could be due to the change in the surface profile and internal structure, minor de-shaping, opening of seam etc. The TIR video and its frames, which is inherently noisy, are restored using Hebbian learning based FIR filter, which performs optimal smoothing in relatively less number of iteration. We have focussed on the hottest region of the ball, i.e. the inner core, and tracked its thermal profile dynamics. Finally we have used multi-layer perceptron model (MLP) to quantify the impact factor with fairly good accuracy.