摘要 |
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 componenets: 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. |