According to the nearest relationship

the labeled value of every codeword in the labeled codebook by the nearest neighbor method was different from its nearest codeword

based on which

using I/matrix

as many as m bits data can be embedded by selectively changing at most m2 indexes in every n=2m VQ_compressed indexes. The simulated results by the computer showed that the method used for information hiding in VQ_compressed images has larger capacity and better secrecy.