| 摘要 |
A method and apparatus for detecting a translation of a portion of video data received from a video output of a computer. The method comprises computing first signatures for each of a plurality of portions of a video frame and a second signature for a portion of a video frame. The second signature is compared with the first signatures and a determination is made whether a portion of video data has been translated according to a result of said comparison. In accordance with a further aspect of the invention analogue video data is received from a video output of a computer, the method comprising converting the analogue video data to digital video data, computing first signatures for each of a plurality of portions of a video frame and second signatures for each of a plurality of portions of a video frame. The first and second signatures are compared to identify portions of a video frame that are the same as other portions of a video frame, the signatures being computed using a function which provides the same value irrespective of the presence of noise in the digital video data. |
