Watermarking

Watermarking, or data hiding, consists of embedding a typically invisible identifier into an image, video or audio file for security reasons.

Watermarking requires both embedding and extraction algorithms. Mathematical techniques can include least-significant bit encoding, transform or image-adaptive techniques and basic M-sequence.

In recent years linear algebra has provided new methods for watermarking. Specifically, the technique of Singular Value Decomposition enables more powerful and sophisticated watermarking that is resistant to attack.