Very fast watermarking by reversible contrast mapping

TL;DR

This paper introduces a highly efficient reversible watermarking method using reversible contrast mapping (RCM), enabling high data embedding rates with low complexity and robustness against cropping, suitable for fast and secure data hiding.

Contribution

The paper presents a novel, low-complexity reversible watermarking scheme based on RCM with a fast lookup table implementation and high embedding capacity.

Findings

High data embedding rates close to existing methods

Low mathematical complexity and fast implementation

Robustness against cropping

Abstract

Reversible contrast mapping (RCM) is a simple integer transform that applies to pairs of pixels. For some pairs of pixels, RCM is invertible, even if the least significant bits (LSBs) of the transformed pixels are lost. The data space occupied by the LSBs is suitable for data hiding. The embedded information bit-rates of the proposed spatial domain reversible watermarking scheme are close to the highest bit-rates reported so far. The scheme does not need additional data compression, and, in terms of mathematical complexity, it appears to be the lowest complexity one proposed up to now. A very fast lookup table implementation is proposed. Robustness against cropping can be ensured as well.