| 摘要 |
The method involves generating base images (B) which contain specific patterns with predetermined positioning within the image and a predetermined luminance level. Marker images (M) containing specific patterns from the base image and their own patterns are also generated. The base images are displayed on screen in a first format. A first optical sensor determines the level of the specific pattern within the base image and a second optical sensor determines the level in the marker image pattern that is common to both it and the base image. The base and marker images are displayed successively according to a transition sequence from the first to the second format with the maker images. A second optical sensor measures the transition from a first format to a second format, allowing generation of a synchronisation signal. The time parameters can then be measured and used to detect the visual code relating to change of sound signal type, particularly when switching from stereo to surround sound. |
