Video Watermarking Technique using Visual Sensibility and Motion Vector [chapter]

Mariko Nakano-Miyatake, Hector Perez-Me
2010 Visual Servoing  
Source: Visual Servoing, Book edited by: Rong-Fong Fung, ISBN 978-953-307-095-7, pp. 234, April 2010, INTECH, Croatia, downloaded from SCIYO.COM www.intechopen.com Visual Servoing 218 its practical use. In the algorithm proposed by Wolfgang et al. (1999) , Just Noticeable Difference (JND) is used, in the Discrete Cosine Transform (DCT) domain, to determine an adequate watermark embedding energy. Hartung and Girod (1998) proposed an algorithm, in which binary data modulated by pseudo-random
more » ... nce is embedded into luminance component of each video frame. Swanson et al. (1998) proposed an algorithm based on the Discrete Wavelet Transform (DWT) through temporal sequences. Kang et al. applied singular value decomposition (SVD) to each frame of video data, and then embedded the watermark signal into the singular values. The watermarking technique in compressed video data, embed the watermark signal into bit sequence compressed by standard coding, such as MPEG-2 and MPEG-4, etc. Generally this technique has lower computational cost, compared with other methods; however the number of watermark bits must be limited by compression rate. In the algorithm proposed by , the watermark signal is embedded only into the I-frames using JND concept, while Biswas et al. (2005) directly embedded the watermark signal into MPEG compressed video sequence, modifying DCT coefficients. Also in the algorithm proposed by Langelaar and Lagendik (2001) , the watermark signal is embedded into the I-frames in the DCT domain. The watermarking algorithms operating during MPEG coding process are inherently robust against standard compression attacks, without increase the compression rate of the video sequence. Liu et al. (2004) proposed an algorithm, where the watermark signal is embedded into the motion vectors, and using the watermarked motion vectors, MPEG bit sequence is generated. While Zhao et al. (2003) proposed a fast algorithm to estimate motion vectors during the compression process, and also they embed the watermark signal, modifying angle and magnitude of the motion vectors. In the algorithm proposed by Ueno (2004) , motion vectors are used to determine an adequate position in DCT coefficients of I-frames for watermark embedding. Noorkami and Mersereau (2006) estimated motion regions, computing spatial distribution of motion through several consecutive frames. Large amount of watermark bits are embedded into dynamic motion regions, while small amount of watermark bits are embedded into statistic regions. In this manner the artifact caused by watermark embedding can be avoided (Noorkami & Mersereau 2006) . In this paper, a video watermarking algorithm is proposed, in which watermark embedding is carried out during MPEG2 coding process. The proposed algorithm uses three criteria based on deficiency of the Human Visual System (HVS) to embed robust watermark, while preserving its imperceptibility. First criterion is based on difference of sensibility of the HVS to basic three color channels (red, green and blue), and second one is based on frequency masking of the HVS proposed by Tong and Venetsanopoulos (1998) . Third criterion is based on deficiency of the HVS to trace high speed motion region, which is related directly to the motion vector of each macro-block. The third criterion is only applied to P-frames, while other two criteria are applied both I-frames and P-frames. In the proposed algorithm, Bframes are excluded from the watermark embedding and detection process to reduce computational complexity. In this manner, watermark embedding and detection processes don't cause any delay in coding and decoding processes. Simulation results show the watermark imperceptibility and robustness against common signal processing and some intentional video frame attacks, such as frame dropping, frame averaging and frame swapping. The watermark imperceptibility is measured using the Peak Signal Noise Ratio (PSNR) and a HVS based objective evaluation proposed by Wang and Bovik (2004) .
doi:10.5772/8552 fatcat:6jsrph6a7naxxojl7kvdk655ba