Video Watermarking Using Spatio-Temporal Masking For ST-DM

Traditional Spread Transform Dither Modulation (ST-DM) is based on the fixed quantization step size, which does not exploit the features of the video contents. Spatio-temporal masking function represents the visual threshold under which human eyes are usually not sensitive. In this paper, we adopts not only the spatial contrast sensitivity function (CSF), the luminance masking function, the contrast masking function but also the spatio-temporal masking function to account for the model of human eyes to the video. we propose using spatio-temporal perceptual model to adaptively select the quantization step size based on the calculated masking function. Experimental results show that the proposed scheme guarantees high peak signal to noise ratio (PSNR). Furthermore, compared with the scheme with fixed step size, the proposed scheme is more robust against temporal frame averaging (TFA) attack.