A robust video watermarking algorithm based on MPEG-2 video compression standard is proposed

which can be implemented efficiently. By using the mapping relationship between video frames’ block DCT coefficients and the full frame DCT coefficients

the proposed scheme does not need to completely decode the host video in watermark embedding and extraction

and thus reduces the operation cost. Experiments show that the method can effectively resist down-scaling attack and Gaussian white noise contamination and MPEG-2 compression.