| 摘要 |
A method and system for preventing a visible video copy being made of a projected image on a screen. In a theater environment, an image is projected upon a screen by a film projector or a video projector. A form of film piracy is accomplished by copying the image on the screen with a video camcorder. Most of these video camcorders are sensitive to the visual spectrum as well as portions of the infra red spectrum. To prevent the copying of a projected image by such a video camcorder, a focused or unfocused image in the infra red spectrum is projected on top of the visual image. This infra red image will not be visible to the audience in the theater. However a recording of the visual image by a video camcorder sensitive to the infra red spectrum will be distorted beyond use. When a focused infra red image is projected onto the screen it may include a message indicating the date and source of the recording. Other messages could be used including a message to the video pirate that he has been caught.
|
