Philips has developed a video watermarking solution for digital cinema, CineFence, which is able to embed every played-out movie in a cinema with a unique code.By marking each video or audio file that is to be distributed with a unique code, CineFence makes it possible for content owners to identify the leak after a pirated copy of their copyrighted content has been detected on the Internet.
CineFence embeds watermarks with information about date, time and place into the picture and soundtracks of movies, allowing moviemakers to trace camcorder-captured copies back to the cinema in which the illegal copying took place
The watermarks are imperceptible to viewers.
The forensic watermarks embedded in the picture and sound by CineFence remain detectable even when camcorder recordings are compressed into formats such as VCD, DivX, and MPEG4.
Source: Forensic tracking movie | CineFence