A new steganographic method based on equivalence class partition

In this paper, we propose two variable LSB hiding schemes. Equivalence class partition transforms information hiding problem into finding the representative element in specific equivalence class. The first step is to construct the equivalence relation, and then to partition the hiding units into different equivalence classes. Finally, the minimizing the distortion in the equivalence class (MDEC) can be used to decrease the distortion caused by hiding operations. In classical LSB hiding schemes, the number of LSB bits used to hiding message is always determined by the length of message, hence, classical LSB hiding schemes cause larger distortion even with fewer messages. Proposed two variable LSB hiding schemes can adapt to the size of information, hence they provide better performance than classical LSB hiding. Theoretical analysis and Extensive experimental results have also indicated that the proposed schemes have good performance.