一种基于MPEG-4的帧间差分能量视频水印算法

针对视频水印的盲检测特性和对时间轴上帧操作的鲁棒性,论文提出了一种基于相邻帧间相关性的视频水印算法,即在预测帧的编码过程中,根据编码器的运动估计和补偿模块提供的运动向量和宏块的编码模式,在残差中嵌入水印数据。在该算法中,用能量替换函数保证嵌入数据不影响视频质量,用重同步策略来保证水印提取时的鲁棒性,并且在水印提取的过程中不需要任何附加信息,是一种盲检测算法。水印的嵌入和提取是在视频的编、解码过程中直接利用编码器提供的信息进行的,因此该算法具有计算复杂性低的特点。实验证明这种方法能够抵抗重编码操作,并且对于帧删除、帧插入和帧置换等攻击也有一定的鲁棒性,而且由于该算法是在预测帧的残差中进行,水印的隐藏效果比较好,生成码流的信噪比也较高。

Inter-Frame Differential Energy Watermarking of MPEG-4 Compressed Video

This paper presents a novel video watermarking scheme based on the correlation between adjacent frames in MPEG-4 video bitstream.The watermark is embedded in P-frames during the encoding and extracted directly from the compressed bitstream without original video.In the scheme,macroblock(MB)coding modes provided by the encoder are used to decide the location of embedding,energy mapping function guarantees the visual quality and re-synchronization strategy improves the robustness of watermarking system.The experimental results indicate that the scheme has several advantages including low computational complexity,strong robustness to re-encoding and frame dropping,low visual degradation and high watermark payload in the low bit rate environment.