Secret Data Hiding in Compressed Video Bit Streams for Privacy Information Protection

The project presents the compressed video bit streams and hiding privacy information to protect videos during transmission or cloud storage. Digital video sometimes needs to be stored and processed in a compressed format to maintain security and privacy. Data hiding approach is necessary to perform in these encoded videos for the purpose of content notation and tampering detection. In this way, data hiding in encoded domain without decoding preserves the confidentiality of the content. Here, data hiding directly in the version of H.264/AVC video stream is approached, which includes the following three parts, i. e. , H.264/AVC video encoding, data embedding, and data extraction. By analyzing the property of H.264/AVC codec, the code words of intra prediction modes, the code words of motion vector differences, and the code words of residual coefficients are coded using H.264 encoding technique. Then, a data hider may embed additional data in to it by using bits replacement technique, without knowing the original video content. Chaos crypto system is used here to encrypt/decrypt secret text data before/after data embedding/extraction. The project simulated results shows that used methods provides better performance in terms of computation efficiency, high data security and video quality after decryption. The parameters such as Mean square error, PSNR, correlation are evaluated to measure its efficiency.