基于多分类的QDCT域大容量H.264/AVC视频信息隐藏算法

提出了一种在开环外的量化离散余弦变换(QDCT )系数上的H.264视频信息隐藏算法。在抑制漂移失真的条件下,对 邻块所需参考像素进行多组分类。其次,充分挖掘帧 内4×4亮度可用QDCT系数对,结合9进制方向调整(EMD)嵌入算法和 矩阵编码,实 现秘密信息的高容量嵌入。同时,通过最多修改一组QDCT系数保证了含密视频的质量。 此外,本文的信息提取算法不需要对含密视频完全解码,只需得到QDCT系数和帧内预测 模式,即可完全提取秘密信息。实验结果表明,本文算法在大幅度提高嵌入容量的同时,对 比特率和视频的质量影响不大。

Multi-classification information hiding algorithm for H.264/AVC video with high capacity in QDCT domain

An information hiding scheme is proposed based on quantized discrete cosine tran sform (QDCT) coefficient of open loop for H.264video in this paper.Under the condition of averting the distortion drift,the reference pixels of the adjacent blocks are classified into multi-groups.Then,9-ary ex ploiting modification direction (EMD) embedding algorithm and matrix coding are used to obtain high hiding capacity by fully exploiting the available QDCT coefficient-pairs of the 4×4blocks in frames.At the same time,the q uality of stego-video can be ensured by changing at most a set of QDCT coefficients.Furthermore,the detection of hidden information only requires to decode the intra QDCT coefficients and intra-prediction mode without decodin g the video completely.The secret information can be extracted completely.Experimental results show that t he proposed method can greatly improve the capacity of hidden information,and also has little effect on the bit r ate and quality of video.