The success of movie releases such as Avatar or Alice in Wonderland marks, for audiences, the coming of age of three-dimensional (3D) stereoscopic cinematography. The launch of 3D television systems allowing direct retransmission of major events has reinforced the trend. This new content presents high added value and increases the risk of illegal copying; therefore, we need to find the means of preserving its intellectual property rights, without imposing additional operational constraints on the underlying chain of production, distribution and consumption.
Watermarking technology presents a response to this need: digital works can be authenticated and traced by inserting additional information that is invisible (transparent) to the user but persistent (robust) against attacks. In practice, the main watermarking challenge is to find a point of operational balance between transparency, robustness and the amount of inserted information. Computational cost is also a key factor in the case of real-time applications.
The state of the art in stereoscopic watermarking is broadly made up of a variety of approaches inherited from 2D/2D+t watermarking. These approaches are based either on spread spectrum (SS) communications theory [COX 02] or on side information (SI) theory [COS 83, SHA 58].
SS techniques offer excellent levels of transparency while guaranteeing robustness for a mark of small size. SI techniques allow the insertion ...