一种基于H.264/AVC的鲁棒性视频水印算法

依据H.264视频编码标准提出一种视频水印方案。结合H.264帧间预测编码的特点以及人类视觉系统原理,选择P帧宏块中的MV作为水印信息嵌入的对象,对MV进行量化处理,得到两个互相独立的区域。根据水印信息的不同,修改MV使其指向不同的区域,对其采用扩频技术来实现水印嵌入,以提高水印的鲁棒性。实验结果表明,新方案能够抵抗重编码压缩、加载噪声、旋转等多种攻击,鲁棒性良好。     

一种基于参数替换的H.264标准水印嵌入算法研究

随着高清数字影像的发展,H.264视频编码方法逐渐成为下一代的视频标准。H.264由于使用了帧内预测编码、运动精度为1/4像素的估计算法使它可获得MPEG-2的2倍以上的压缩比和视频质量,而获得广泛应用。但是在H.264视频中嵌入水印用传统视频水印的方法无法有效地完成,在对视频编码的帧内预测模型研究的基础上,设计了一种快速的水印嵌入算法,基本实现了在H.264编码过程中水印提取的盲检测,其低算法复杂度可以满足视频实时处理的需要。     

基于H.264误差漂移补偿的鲁棒性视频水印算法

针对现有基于H.264的视频水印算法存在误差漂移的问题,在分析了误差漂移产生原因的基础上,提出了一种抑制误差漂移的鲁棒性视频水印新算法.通过调制H.264编码中Ⅰ帧量化后的4 ×4 DCT系数来实现水印的嵌入,并对帧内预测量化后满足特定条件的DCT子块的最后一行、列进行补偿和对帧间预测进行补偿,有效地抑制了帧内、帧间误差漂移.另外,该算法结合CAVLC编码来调制量化后的DCT残差系数,使整体码流变动较小,并且算法能够根据不同视频序列自适应地调节嵌入容量及嵌入位置,具有较好的灵活性和鲁棒性.在水印提取过程中,不需要原始视频的参与,即可实现盲提取.仿真实验结果表明,该算法在具有良好不可见性的前提下,对压缩码率影响较小,能够较好地抵抗噪声、帧剪切、重编码等攻击.     

高清实时视频流脆弱性数字水印技术研究

为解决高清实时视频流完整性验证问题,文章提出了一种H.264脆弱性数字水印算法,并基于该算法提出了认证方案。通过对水印特征的分析,提出在H.264视频编码时根据I帧的低频DCT量化系数及密钥生成水印信息,嵌入到I帧的高频DCT量化系数中及P帧的DCT量化系数中,并在视频的解码阶段进行检测及验证,水印提取不需要原始视频的参与,属于盲检测。实验结果表明,该文中所提出的算法及验证方案对H.264视频的图像质量、输出码率及编码速度影响较小,并能有效的检测各类攻击,具有较强的实用性及有效性。     

一种抗H．264压缩攻击的视频水印方案

提出了一种能较好地抗H．264压缩的鲁棒视频水印方法。根据H．264中DCT变换系数的分布和人眼视觉的特点,选择1帧的亮度残差分量4×4矩阵中次对角线位置上的四个中频系数嵌入水印。分析水印信息受压缩攻击出错的原因,并结合纠错编码的原理,提出了一种根据中频系数奇偶性嵌入可抗压缩的鲁棒性水印的方法,有效的提高水印的抗压缩性。试验结果表明,提出的方法对抵抗H．264压缩、准确提取水印具有显著效果。     

基于H.264码流的数字视频水印算法研究

随着数字视频水印技术被广泛应用于视频信息的版权保护,提出一种基于H.264码流的数字视频水印方案.根据经典算法 H&G 算法的部分解码的思想,通过纹理复杂度参数和帧内预测方向在每个宏块中选择合适的4×4块,并根据DCT系数特点,选择4×4块的一个中频系数来嵌入水印.结合常用的内置式水印的嵌入方法,通过调制 DCT 系数的一个中频系数的奇偶性关系,完成水印在 I 帧的嵌入.通过对标准视频序列的测试,证明了该算法在H.264标准上的可行性.     

一种基于FFMPEG系统的视频水印算法

提出一种基于FFMPEG系统的MPEG-2视频水印算法,解决了视频水印中不可避免的视频编解码问题。将水印图像和水印属性转成二进制比特流,作为嵌入视频的水印信息,提取时不需预知水印的尺寸信息就能恢复。同时在每个嵌入帧的起始部位嵌入标志序列,识别已嵌入水印的帧提取水印,而无需重新进入编码过程。实验结果表明,这种方案实现便捷,省时高效,且具有较好的不可见性和鲁棒性。     

基于H.264低比特率视频流的半脆弱盲水印算法实现

本文提出一种基于H.264低比特率视频流的半脆弱盲水印方法,通过在H.264特有的的帧内预测和运动向量预测中分别嵌入鲁棒水印和脆弱水印,达到版权保护和内容完整性认证的双重目的.通过在嵌入强度和预测模式选择的拉格朗日乘子中引入H.264量化因子,增强了水印对重量化编码的抵抗力,取得更好的率失真平衡,减小水印嵌入对视频流比特率的影响.该算法可以实现水印的快速嵌入提取,满足视频实时处理的要求,实验结果证明了该算法的有效性.     

基于H.264帧内预测模式的信息隐藏算法

根据H.264标准编码的特点,提出一种较高性能的信息隐藏方案。文章分析H.264中I4×4亮度块的9种帧内预测模式,以及最优模式的选择策略,将I4×4亮度块的9种帧内预测模式作为备选宿主,利用信息嵌入算法将信息嵌入到视频中。这样降低了信息隐藏过程中预测模式调整对视频质量的影响,并能提高嵌入信息数据量。     

一种基于秘密共享与运动矢量的视频水印算法

本文在"压缩嵌入联合编码"框架下,提出一种基于秘密共享和信息分级保护的水印生成算法.与用算术编码压缩水印相比,本文的秘密共享方案在保证水印可认证性的前提下大幅度减少了信息嵌入量,同时对嵌入的信息依其重要程度进行分级保护,有效地增强了水印的鲁棒性.在此基础上,利用当前宏块与其周围宏块的运动矢量的相关性,提出一种基于运动矢量的自适应视频水印算法,可有效控制运动矢量的修改幅度,保证视频质量.实验表明该方案能保持很小的峰值信噪比损失和较好的视觉效果,且对于删帧攻击具有较强的鲁棒性.     

A Video Watermarking DRM Metho d Based on H.264 Compressed Domain with Low Bit-Rate Increasement

It gets more and more important for video copyright protection, it is necessary to provide e?cient H.264 compression domain watermarking for video Digital rights management(DRM). A new watermarking method based on H.264 compressed domain is proposed for video DRM, in which the embedding and extracting procedure are performed using the syntactic elements of the com-pressed bit stream. In this way, complete decoding is un-necessary in both embedding and extracting processes. Based on the analysis of the time and space, some appro-priate sub-blocks are selected for embedding watermarks, increasing watermark robustness while reducing the dec-lination of the visual quality. In order to avoid bit-rate increasing and strengthen the security of the proposed video watermarking scheme, only a set of nonzero coe?-cients quantized in different parts of macroblocks is chosen for inserting watermark. The experiment results show the proposed scheme can achieve excellent robustness against some common attacks, the proposed scheme is secure and e?cient for video content DRM protection.     

A new video watermarking algorithm based on 1D DFT and Radon transform

In this paper, we propose a new video watermarking algorithm based on the 1D DFT (one-dimensional discrete Fourier transform) and Radon transform. The 1D DFT for a video sequence generates an ideal domain, in which the spatial information is still kept and the temporal information is obtained. With detailed analysis and calculation, we choose the frames with highest temporal frequencies to embed the fence-shaped watermark pattern in the Radon transform domain of the selected frames. The adaptive embedding strength for different locations keeps the fidelity of the watermarked video. The performance of the proposed algorithm is evaluated by video compression standard H.264 with three different bit rates; geometric attacks such as rotation, translation, and aspect-ratio changes; and other attacks like frame drop, frame swap, spatial filtering, noise addition, lighting change, and histogram equalization. The main contributions of this paper are the introduction of the 1D DFT along temporal direction for watermarking that enables the robustness against video compression, and the Radon transform-based watermark embedding and extraction that produces the robustness against geometric transformations. One of the most important advantages of this video watermarking algorithm is its simplicity and practicality.     

基于Tornado码的视频抗误码策略

提出了一种适用于H.264编解码过程的抗误码策略,针对自适应FMO模型,在其传输过程中加入Tornado算法,并根据图像强弱运动部分错误掩盖方法的不同,合理地分配传输过程中结点位置,以保证强运动部分获得更高的恢复率,更好地提高图像抗误码性能.实验证明,该策略有效地提高了恢复图像的质量.     

Robust Video Watermarking of H.264/AVC

A robust video watermarking scheme of the state-of-the-art video coding standard H.264/AVC is proposed in this brief. 2-D 8-bit watermarks such as detailed company trademarks or logos can be used as inconvertible watermark for copyright protection. A grayscale watermark pattern is first modified to accommodate the H.264/AVC computational constraints, and then embedded into video data in the compressed domain. With the proposed method, the video watermarking scheme can achieve high robustness and good visual quality without increasing the overall bit-rate. Experimental results show that our algorithm can robustly survive transcoding process and strong common signal processing attacks, such as bit-rate reduction, Gaussian filtering and contrast enhancement     

A novel watermarking scheme for H.264/AVC video authentication

As the H.264/AVC-based video products become more and more popular, issues of copyright protection and authentication that are appropriate for this standard will be very important. In this paper, a content-based authentication watermarking scheme for H.264/AVC video is proposed. Considering the new feature of H.264/AVC, the content-based authentication code for spatial tampering is firstly generated using the reliable features extracted from video frame blocks. The authentication code, which can detect malicious manipulations but allow recompression, is embedded into the DCT coefficients in diagonal positions using a novel modulation method. Spatial tampering can be located by comparing the extracted and the original feature-based watermarks. In addition, combining ECC and interleaving coding, the frame index of each video frame is used as watermark information and embedded in the residual coefficients. Temporal tampering can be detected by the mismatch between the extracted and the observed frame index. Experimental results show that the proposed scheme can discriminate the malicious tampering from the mild signal processing. The tampered location can also be approximately determined according to the glide window and the predefined threshold.     

H.264帧间模式选择水印算法研究

针对H.264/AVC视频编码标准,提出一种基于帧间模式选择的视频水印算法。在亚宏块模式选择的基础上,算法先对二值图像进行Arnold置乱以及turbo码编码形成待嵌入的水印序列;然后,根据水印数据修改亚宏块模式以改变子块数目的奇偶性,并将修改前后SAD值变化最小的亚宏块作为嵌入域;最后,通过隔帧嵌入、增大滤波器滤波强度来降低水印的嵌入对视频质量的影响。仿真结果表明,在不影响水印正确提取的前提下,算法对视频码率影响较小,具有很好的抗噪声能力,并且在视频PSNR方面能取得较好的效果。      

基于纹理特征的H.264/AVC顽健视频水印算法

在分析现有视频水印算法的基础上,结合H.264压缩编码标准的特性,提出了一种新的基于纹理特征的视频顽健水印算法。算法先对当前帧4×4块进行整数离散余弦变换,判断其是否是纹理块,再采用能量差的方式自适应选择系数嵌入水印。实验结果表明,该算法对视频质量和码率的影响较小,并且能有效抵抗高斯噪声、低通滤波、重编码等常见的视频水印攻击。