| 摘要 |
<p>To directly or indirectly prevent productions such as movies and videos, displayed on display units such as screens and displays, from being illegally photographed by image photographing devices such as video cameras, and distributed. A display operation state is switched by one or a plurality of operations out of frame rate switching, scanning direction switching, brightness switching, scanning phase switching, scanning pattern switching, scanning time position switching and scanning interval switching to produce stripe patterns on a re-photographed image and hence lower an image quality. In addition, a display operation state is switched based on a value offered by operation state control information. Operation state control information consists of information on an image itself, image display unit, image display facility, information display date, image control or the like so that actions/measures against re-photographing can be taken by extracting operation state control information from the re-photographed image.</p> |
