| 摘要 |
The method comprises capturing an electronic image of a workpiece such as a tile by a camera (8), analysing the electronic image to derive a histogram (H, fig. 2) of tonal variation in the image, deriving a numerical representation of the tonal variation in the workpiece by the use of an algorithm operative upon probabilities (P[0], P[1], ..., fig. 2) derived from the said histogram. The workpieces may be moving past a workstation (7) on which the camera (8) may be mounted. The images may be stored on a control processor, which in turn is used to compute the tone features T, of the workpieces. It also calculates the probability of the occurrence of such tones, and compares the resulting tone features with a predetermined tone to determine the similarities between the tone features and thereby ensures that workpiece is directed to a specific collection point (10) in which all the workpieces with similar tones are collected. |
