A recursive method for identifying isotropic zones in a video image; a device for detecting movement and noise in a sequence of images

摘要

The method enables zones to be defined in a television image, each zone consisting of a group of contiguous points in the image that have the same property, that of being in movement for example. The zones are numbered Z1, Z2....and each has a "state vector" whose components represent characteristics of the zone, e.g. the number of points contained in the zone. The assignment of a point to a zone is made as a function of the zone numbers of the neighbouring point which precedes it in the same line and of the neighbouring point in the preceding line. If these two neighbouring points had previously been assigned to two different zones, these two zones are deemed to be united, i.e. it is recognised that they are really one and the same zone. The device assigns a zone number to each point in movement. The points whose movement is due to noise are detected by the fact that they belong to zones of very small size.