METHOD FOR THE CALCULATION OF A CHANGE CRITERION IN A PICTURE SEQUENCE AND USE THEREOF

摘要

To distinguish whether changes occur in an image sequence or not, a change criterion is necessary. In the invention, this change criterion is derived from the frame differences, the frequency distribution of which is evaluated. This frequency distribution is formed over at least two images. For each frequency distribution, the maximum in the range of small frame differences and the turning points nearest to the maximum are determined. From this maximum and lower turning point, a decider threshold value is determined which is averaged with the decider threshold values of the other frequency distributions to form the change criterion. These measures provide a change criterion adapted to interference, for example the camera noise.