A Robust, Privacy Preserving Secret Data Concealing Embedding Technique into Encrypted Video Stream

With tremendously increasing demand for multimedia communication, it is essential to safeguard the video data from various attacks during its transmission over internet. Video encryption ensures privacy and security of the video content. For the purpose of authentication or to identify tampering if any, secret information is concealed in these encrypted videos. This paper puts forward an efficient and robust methodology for embedding the secret information directly into encrypted videos, which guarantees the confidentiality of the video content. The input video is first compressed using the popular H.264/AVC compression technique and by analyzing the properties of H.264 encoding technique, the three portions containing the sensitive data are encrypted. A standard RC4 stream cipher has been employed for encrypting the codewords of Motion vector differences, Intra prediction modes and Residual coefficients. The secret data can then be hidden by the data hider using a unique Codeword substitution technique without being aware of the video contents. Thus the technique ensures confidentiality of the video content. The hidden data can then be directly extracted by the intended authenticated receiver even without decrypting the video sequence. To validate the feasibility and the performance of the proposed work, the result metrics PSNR, SSIM and VQM have been estimated.