Histogram based multilevel reversible data hiding scheme using simple and absolute difference images

In this paper, a multilevel reversible data hiding scheme based on simple and absolute differences of non overlapping blocks of a cover image is proposed. Histogram of each difference block of the cover image is generated and the positive and negative peak points of this histogram are used to hide the secret data bits by shifting these peak points. Number of secret bits hidden into each positive peak point is exactly one while number of secret bits hidden into each negative peak point are more than one which increases the hiding capacity of the cover image. Proposed scheme achieves high hiding capacity than existing reversible data hiding schemes while keeping less distortion in the marked image.