Scientists have developed a technology that can determine from an illegal film recording where in the theater it was filmed. To do this, they slightly alter the soundtrack during mixing, then calculate the microphone position with about 0.44 meter accuracy. Tests showed sound quality is not affected, but practical use faces a serious obstacle, matching a seat to a specific person, which requires collecting cinema visitors personal data.
Scientists have succeeded in developing a technology that makes it possible to determine the seat in a movie theater from which an illegal camcorder recording was made. In theory, this means that after an illegal copy appears on the market, it will be possible to determine where and by whom it was made (knowing the personal data of the cinema visitors).To apply the new method, the scientists propose making some changes to the film’s soundtrack at the mixing stage: special software should “adjust” the shape of the sound waves for each audio channel in the movie theater.
Usually in movie theaters, different channels are played through different speakers whose locations are known. The scientists created a computer program that can reconstruct the microphone’s location from the resulting sound that was recorded.
Practical tests of the software showed that the accuracy of determining the microphone’s location is about 0.44 meters. This is quite enough to identify the seat in the theater where the pirate was sitting. In addition, testing showed that the changes made to the sound do not affect the quality of the perceived audio in any way.
Despite the effectiveness of the new technology, according to the researchers, its practical application may face a number of difficulties. The main one is collecting personal information about cinema visitors so that the row and seat number obtained as a result of computer analysis can be “linked” to a specific person.