| 摘要 |
PURPOSE: To provide a method and a system with which a code is encoded into digital image, this image is monitored and it is judged whether that image is derivated from the encoded image or not. CONSTITUTION: These method and system are provided for embedding a code into the visible image of both digital display and print or film. The code is embedded into the visible image so as not to be separated, and continuously exists even when performing size change or image conversion such as conversion to the print or film and reconversion to a digital form. A code point is selected among the pixels of original image, the code point and the pixel values of pixels around that point are adjusted just for quantity detectable for a digital scanner, this adjusted code point forms the digital code and this is stored for identifying the relevant image derivated from the image later. The code is embedded into the image by searching relatively extreme values in the continuous space of pixel values and selecting the code point among these values. |
