Robust video watermarking based on discrete fractional Fourier transform

A video watermarking technique based on discrete fractional Fourier transform (DFRFT) is proposed. Each frame of an original video is first decomposed into two-dimensional (2-D) multiresolution representations by 2-D discrete wavelet transforms (DWT) along the spatial axis. Then the wavelet coefficient frames in each group of pictures (GOP. each GOP has 16 frames) are transformed into DFRFT coefficient frames by one-dimensional (1-D) DFRFT along the temporal axis. The watermark is embedded into each DFRFT coefficient frame in the GOP, and the angular parameter of the DFRFT can be changed to adapt itself to the original video. Experimental results show that the proposed technique is robust enough against the attacks of frame dropping, averaging and lossy compression.