Secure Steganographic Algorithm in JPEG Images

Although it is very meaningful to embed secret messages into a cover image in JPEG format, an analyst can detect the presence of hidden data according to a change of DCT coefficient histogram or an increase of blockiness parameter. In order to improve the security of embedded information, a secure steganographic technique is proposed, in which AC DCT coefficients with non-zero values are used to carry the secret bits when the DCT coefficient histogram and blockiness property are reserved. This way, the histogram-based and blockiness-based steganalyses are effectively resisted. Simulation results show that the proposed method is secure for cover images with quality factor more than 35.