A data-embedding technique for digital images

A number of schemes have recently been proposed for hiding data in digital audio, still images and video. The approaches differ in the amount of distortion brought to the original host signal, their robustness to compression and other signal processing operations, and the amount of data which can be embedded. In this paper we present a technique for embedding data in digital still images. The proposed scheme employs digital communication techniques. The information is embedded in the frequency domain by modulating selected DFT values of the image. Properties of the human visual system are employed in choosing the DFT values to be modulated. The selected DFT values are grouped into different frequency bands. A different label can then be embedded in each of the frequency bands. The performance of the proposed scheme is assessed by computer simulations. The original image is not required to recover the embedded information