Steganography is a well-known topic in Information Security. In Steganography, how to embed a data into host file without being detected is the most important issue. Unfortunately, embedding process will make some modification in host file. For a digital image, pixel modification makes distortion and more distortion makes the embedded data be detected easily. So, we propose a scheme that can reduce pixel modification efficiently to decrease distortion caused by embedding process. By a tree structure and Majority Parity Check(MPC), to reduce pixel modification when hiding a data. Our scheme is a plug-in linear process to help most existing data hiding algorithms.