Errorless Robust JPEG Steganography Using Steganographic Polar Codes

Abstract

Recently, a robust steganographic algorithm that achieves errorless robustness against JPEG recompression is proposed. The method evaluates the behavior of DCT coefficients after recompression using the local JPEG encoder to select robust coefficients and sets the other coefficients as wet cost. Combining the lattice embedding scheme, the method is errorless by construction. However, the authors only concern with the success rate under theoretical embedding, while the success rate of the implementation with practical steganographic codes is not verified. In this letter, we implement the method with two steganographic codes, i.e., steganographic polar code and syndrome-trellis code. By analyzing the possibility of success embedding of two steganographic codes under wet paper embedding, we discover that steganographic polar code achieves success embedding with a larger number of wet coefficients compared with syndrome-trellis code, which makes steganographic polar code more suitable under the errorless robust embedding paradigm. The experimental results show that the combination of steganographic polar code and errorless robust embedding achieves a higher success rate compared with the implementation with syndrome-trellis code under close security performance.