Abstract: A dual video watermarking technique based on energy difference ratio and spread spectrum was proposed.Firstly, at the infra prediction, transform and quantization stage, it embeded robust watermarking by low-mid frequency DCT coefficients of direct permutation. Further more, semi fragile watermarking was embedded by energy-difference-rado algorithm. And besides, watermark extraction in this algorithm enabled the blind examination. Experimental results show that the proposed method will not affect the size of video files,and also has strong robustness under attacks such as rcquantization, block-deletion and collusion.

Key words: Dual video watermarking, Spread spectrum, Energy difference ratio, I-frame