提出了一种基于帧内预测模式的HEVC视频信息隐藏算法。在预测编码过程中,针对纹理复杂度高的帧内4×4亮度块调制预测模式,利用拉格朗日率失真模型自适应选取帧内编码模式,以决定是否嵌入隐秘信息。为了降低因信息隐藏导致视频质量下降,将最优预测模式变为与隐秘信息奇偶性相匹配的模式中率失真开销最小的预测模式,信息的提取过程只需对码流中的预测模式解码即可。实验仿真结果表明,本文算法能很好地保证视频质量,对视频流的码率影响很小。
An information hiding algorithm for HEVC based on intra prediction is proposed. We are modi- fying the intra prediction modes in 4 × 4 luminance blocks with high-complexity texture during the process of predictive coding. Depending on the coding patterns of intra frame with Lagrangian model can decide whether secret information will be embedded. For reducing the impact of modifying the prediction mode on the quality of video, the prediction mode will replace the best mode with the substitute mode which is the one with the least Lagrangian cost among those matching parities with the secret informa- tion. The extraction of information merely requires to decode the intra prediction mode from the bit stream. Experimental results show that the proposed hiding algorithm can effectively embed information with little influence on the bit rate and quality of the cover video.