Digital audio watermarking and image watermarking for information security

The article covers a brief summary of modern approaches for embedding additional data in audio signals. It could have many causes - for the purposes of access control or identification related to particular type of audio. This top-secret information is not “visible” for a user. The leading determination for watermarking by audio is to defend beside probable extortions in the audio records and for copyright harm or illegal altering; reality for such information can be unsure by audio watermarking. Steganography and cryptography are two techniques these techniques are related in the manner that they together are used to safeguard private facts. There is lack in characteristic of original image we recommend a generalized form of Reversible Contrast Mapping (RCM) is an in complex integer transform that applies to pairs of pixels. For image watermarking Contrast mapping is invertible procedure, because least significant bits (LSBs) of the transformed pixels are forfeit. The data space occupied by the LSBs is expedient for information hiding. The embedded information bit-rates of reversible watermarking structure are highest bit-rates till date. The system does not need further records compression, and, in terms of mathematical complexity, it is having lowest complexity. Also robustness against cropping can be guaranteed.