Adaptive Image Steganography in the Difference Value of Discrete Cosine Transform Coefficients

Steganography is the science and art to conceal the existence of communication, by hiding information in a digital media, the existence of communication is hidden from the enemy's point of view. steganography in the frequency transform coefficients and in particular the discrete cosine transform (DCT), due to its low detection capability, is one of the most common and active areas of steganography among researchers. But most of the methods in this area have used embedding directly in the DCT coefficients. The main purpose of the proposed method in this paper is to suggest a different embedding platform in this field. In the proposed embedding method, the DCT transformation coefficients are coupled and embedding is on the difference value of each couple. The embedding is done in such a way that the receiver can extract the data completely by calculating the difference in the value of the neighboring pairs. The proposed method is an adaptive method because the number of embedded bits in each pair of coefficients is dependent on the difference between them. The results of various experiments show that the proposed method, with the preservation of the quality of the stego image at a desirable level and having a reasonable embedding capacity, is less likely to be detected in relation to the existing steganalysis attacks.