A comparative study of PVD-based schemes for data hiding in digital images

Unlike data encryption, steganography provides a crucial means for hiding confidential data into cover media so that the unauthorized person will not be aware of the existence of this data. This is particularly useful for protecting sensitive data that needs to be transmitted over a public access network such as the Internet. Several schemes have been proposed based on pixel value differencing with an attempt to increase the embedding capacity of secret data into digital images without significant loss in the perceived quality of the cover images. This paper aims to survey a number of methods that depend on or extend the pixel value differencing scheme. It also provides empirical comparison and discussion of the differences between the various methods.