一种提取视频电磁泄漏信息同步特征的方法

检测/截获计算机电磁泄漏的视频信息,其关键技术是图像信息的恢复还原。该文用类Harr小波提取不同程度倾斜的视频图像的纹理特征,测量纹理的倾斜角度,用于自动控制行同步参数的调整,直到行同步的精度满足要求,实现截获的计算机视频泄漏信息(图像)的稳定恢复再现。

A Method for Extracting the Synchro Characters in the Video Information Leaked by a Computer System

Some common characters in the video information leaked by a computers system are the texture aracteristics which are composed of moving black areas of a reconstructed image from the leaked video formation. The texture characteristics are quite different with the varying of synchronal frequency. The moving eed of the texture increases when the synchronal error becomes larger. And the moving direction is decided by e sign of the error. According to these features, a similar Harr Wavelet method is used to extract the synchronal aracters in the video information leaked by a computer system. Based on these synchronal characters, the angles lted by the synchronal error are used to adjust the frequency of the synchronal pulses until the synchronal curacy is enough for steady display.