Watermarking robust against analog VCR recording

Watermarking techniques are now in the spotlight to protect their copyrights. Enough verifications of robustness against analog VCR recording, however, have not been performed explicitly in previous work while analog copied contents have raised their fidelity. We study on a watermarking technique that has durability against analog VCR copying. We found that the watermarks well survive after D/A and A/D conversions and VCR recording when they are embedded in the wavelet transform domain with three times horizontal and one time vertical 2-to-1 decimations. Our method increases the relative power of the watermark signals using the spread spectrum technique. Additionally, it varies embedding density as well as the magnitude of the watermark signal as an adaptive control. We embedded 64-bit information into a video sequence using the proposed method and confirmed that we can detect the watermarks correctly even from the analog copies recorded with the VHS standard mode.