A method and an apparatus for marking image sequences, a support comprising such marks, and a method and an apparatus for identifying such marks

摘要

A method for marking a series of images such as a film for identification. A copy of the film is associated with a series of pseudorandom values that correspond to fields of a virtual grid covering an image (10). A visible mark is put (630) into the field corresponding to the first pseudo-random value in M consecutive images followed by (640) a number N of unmarked images (N ‰¥ 0) before repeating this using the next pseudo-random value. The visible marks are advantageously quite small so as to keep user disturbance to a minimum, but they may also be quite visible. Also provided is a marking apparatus (700).