Using distinctive colour signatures to capture team behaviour during matches

To capture team behaviour, kinematic variables, such as the surface area and the geometrical centre of the team, have been used. Although these variables have shown interesting results in capturing team behaviour, they reduce individual differences to a unique measure, losing the contribution of each player to the team. Using infrared (IR) dyes, it is possible for each player to have a distinctive colour signature to capture their behaviour online. The first stage of this study consisted in the selection of appropriate IR dyes with peak absorbance at different wavelengths (800nm, 910nm, 949nm and 1031nm) that were dissolved in solutions and diluted two times with a 1/5 ratio. To assess the contrast between the solutions, they were applied in a 6 × 4 chessboard. A unique colour signature was made composing an image from three different charge-coupled devices (CCDs) (one in the visible spectral region and two in the near IR) that were used like the RGB colour system. The IR markers absorbing at shorter wavelengths (800nm and 910nm) have a darker tone in the range 750-900nm and appear white between 900-1900nm. The markers with longer absorption wavelengths have a dark tone in both regions. We calibrated the images from the three CCDs and composed an image in which we give a different colour signature to each square. It is possible to create distinctive colour signatures using the coordinates from three different images.