An automated system for monitoring the visual quality and authenticity of satellite video streams using a fragile watermarking approach

Abstract

This study presents an automatic, fragile-watermarking-based scheme for monitoring the visual quality and authenticity of video streams broadcast by a communications satellite. In the proposed approach, watermark information is embedded in designated motion vectors within the frames of the original video stream prior to it encryption, modulation and transmission to the satellite. Following the reception of the video stream at a terrestrial monitoring system, the watermark information is extracted and compared to that embedded in the original frames. It is shown that by monitoring the mean square error (MSE) of the extracted watermark relative to the original version, reliable estimates of the visual quality of the transmitted video stream can be obtained. Furthermore, the experimental results indicate that the watermarking scheme successfully identifies various common forms of interference, namely recompression attacks, frame removals, frame substitutions, and so forth. Therefore, by monitoring the watermark extraction results on a continuous basis, the degree of signal interference can be automatically determined and an appropriate alarm signal generated to prompt the necessary response.