MPEG-2 digital video watermarking technique

For protecting the authenticity of multimedia objects, watermarking plays a vital role, since, they are much easier to get copied, exchanged and modified these days. Conventional watermarking techniques as available are not always competent enough to protect the authenticity of multimedia objects as they are usually applied in the uncompressed domain. To address this deficiency, the subject paper presents a new compressed domain video watermarking scheme. The method proposed herein embeds several binary images decomposed from a single watermarked image into different scenes in a video sequence. The spatial spread spectrum watermark is embedded directly into the compressed bit streams by modifying the discrete cosine transform coefficients. In order to embed the watermark with minimum loss in image fidelity, a visual mask based on local image characteristics is incorporated. Simulation experiments demonstrate that the developed technique yields effective and robust protection against conventional spatial strikes, viz. scaling and frame averaging besides temporal attacks.