An adaptive data hiding algorithm with low bitrate growth for H.264/AVC video stream

H.264/Advanced Video Coding (AVC) video is one of the most used multimedia covers. In this paper, a novel scheme is proposed to embed secret data into the H.264/AVC video host. The main idea of the proposed scheme is that two secret digits in a (2n+1)-ary notational system are embedded into 2n nonzero Quantized Discrete Cosine Transform (QDCT) coefficients of luminance component in a macroblock and, at most, only two nonzero QDCT coefficients are increased or decreased by 2, respectively. Thus, the number of modified coefficients is small and it can guarantee a high Peak Signal-to-Noise Ratio (PSNR) value, low distortion and slight increase in bitrate after data embedding. Experimental results show that the average degradation in terms of PSNR is 2.48dB and the proposed algorithm can keep increase by no more than 0.35% in bitrate. When compared with several related schemes in the same embedding capacity, the proposed scheme indeed has an advantage in low bitrate growth.