Reversible data hiding base on VQ and halftoning technique

Data hiding conceals the existence of secret information while cryptography protects the content of messages. A reversible data hiding is an algorithm, which can recover the original image losslessly from the stego-image after the hidden data have been extracted. In this paper, we propose a method that combines reversible data hiding, halftoning and vector quantization (VQ) technique to embed a grayscale image in other image. Experimental results show the proposed method can payload the larger grayscale secret image while keeping a high visual quality in stego-image and extracting secret image.