Digital watermarking is the process of embedding information into a signal (e.g. audio, video or pictures) in a way that is difficult to remove.
Watermarking has become increasingly important to enable copyright protection and ownership verification.
An interesting feature of this watermarking technique is that destroying it requires noise of high amplitude to be added to all frequency bands.
Although PN sequence detection is possible by using heuristic approaches such as evolutionary algorithms, the high computational cost of this task can make it impractical.
When evolutionary algorithms are used as a means to extract the hidden information, the process is called Evolutionary Hidden Information Detection, whether fitness approximation approaches are used as a tool to accelerate the process or not.