Steganalysis of LSB Matching in Gray Images Based on Regional Correlation Analysis

LSB matching improves the security of hidden message through changing the pixelpsilas LSB randomly, which breaks the rules of pairs of values in LSB replacement. This paper proposed a new steganalysis technique which aims at LSB matching embedding based on the local areapsilas correlation in grayscale images. The detection method defines the correlation between regional pixels as the difference between the sum of 8-neighbor pixels and the central pixel. The existence of embedded information can be detected by observing the change of the regional correlation before and after embedding. Compared with the existing algorithms, the advantages of the proposed method includes simplicity, computational efficiency and low false positive rate. The detection achieves high reliability when embedding rate is above 30%.