| 摘要 |
<p>A method of detecting a fault on an imaging device, such as a scanner window, comprising the steps of: (a) capturing an image of an article viewable through an imaging device 102, the imaging device being divided into one or more cells, with each cell being assigned to a portion of the image; (b) processing the image to determine whether any of the cells contain computer-recognisable data; (c) If a cell does contain computer-recognisable data, analysis the data to determine if it is recognisable to a pre-determined probability of success 104; (d) maintaining a first count 106 for each cell when the computer-recognisable data contained in that cell is recognised and a second count 108 when it is not. Steps (a) to (d) are repeated for a plurality of articles and an error signal is generated when a threshold based on the first and second counts is reached during a fixed number of successive repetitions of steps (a) to (d).</p> |
