| 摘要 |
<p>Disclosed are a warning generation method and a security system using edge detection of a video image signal. The warning generation method includes the steps of : a) decoding video image signals and extracting luminance signals from the decoded video image signals; b) filtering high-frequency components of the extracted luminance signals and detecting edge components within the video image signals; c) extracting only values within a range of a predetermined first threshold value form the detected edge components; d) accumulating the detected edge components for one video image; and e) operating a warning device if an accumulation value is smaller than a predetermined second threshold value. When an intruder blinds a camera lens using a cover, the security system can generate a warning by identifying the fact that the camera is blinded by the cover.</p> |
