Digital Watermarking Tecniques and Authentication For Robust and Reversible Watermarking

Image Authentication (IA) techniques are generally classified into two classes: Active and Passive Authentication. Active authentication is the process of embedding a symbol within the media and guarantees its ownership, it includes two types digital watermarking and digital signatures. Passive authentication is used to detect tampering. It is classified as forgery – dependent methods and forgery independent

methods. It shown .

Techniques for For the authentication method, prior image information is indispensable. It concerns the hiding of data where such coding is

integrated into the image at the time of generation. The originality of the image is checked by this code. In addition, active authentication approaches are categorized as digital watermarking and digital signatures in two