動きベクトルを用いた動画像電子透かしの検討

Abstract

Motion vectors are employed in motion compensation (MC) predictive coding for video sequences. This paper presents a watermarking algorithm using motion vectors， where watermark information is embedded in motion vector components (horizontal and/or veｒical).The motion vectors are treated in terms of integer-pixel accuracy or half-pixel accuracy. According to“0" or“1"of the watermark bit code， vector components are forced to have odd or even values in the former case，and integer or half-pixel values in the latter case. In our simulation experiments，the influence of the watermarking process on coded-decoded image qualities is investigated. Better image qualities are obtained when watermark bits are embedded in horizontal components than in vertical components. The SNR degradation obtain.ed is about 1dB compared with images without watermarking.