A Novel Data Hiding Method for Grayscale Images Based on Pixel-Value Differencing and Modulus Function

The purpose of this paper is to present a novel data hiding technique which is based on pixel-value differencing and modulus function and is capable of reducing the distortion of stego image for graylevel image. In the proposed scheme, we take two close pixels as a block to hide secret data where the payload of each block is determined by pixel-value. differencing. In order to obtain a better stego-image quality, we hide more data into the blocks with the higher difference value than that the blocks with the smaller difference value. In data embedding procedure, we propose a novel technique which is capable of reducing the distortion of stego image with the minimal. In our new scheme, we adopt the non-decimal number system to represent the secret data, and utilize the modulus function to minimize the possible distortion after hiding data. Since there are six degrees of payload are used in our method, we present the revision method to ensure the consistency of degree for each block. Therefore, the proposed scheme is blind because the original image is unnecessary in the data extraction. The experimental results demonstrate that the proposed scheme is greatly reducing distortion and its performance is better than that of those existing schemes.