关键词: H.264, 视频隐写, 鉴权播放, 帧内预测, 符号编码

Abstract: In the multimedia content distribution and playing system, files played were limited without compromising users' experience. Firstly, binary images were selected adaptively and embedded during the intra prediction by modifying AC coefficients of specific locations. Then, the extracted watermark was matched with the binary image selected adaptively. If not matched properly, the video could not continue to be decoded and played. The experimental results demonstrate watermark algorithm has high robustness. After watermarks are embedded, video Peak Signal-to-Noise Ratio (PSNR) and rate almost remain unchanged. The proposed algorithm also has low complexity and strong practicability, and illegal videos can be filtered effectively.

Key words: H.264, steganography, authentication playing, intra prediction, symbol encoding