Steganography with Highly Random Linear Congruential Generator for Security Enhancement

Steganography means embedding messages into other media intended to avoid unauthorized parties from intervening. In general, the message insertion process is performed sequentially starting from the first pixel to the last pixel or else being initialized from the outer edge of the cover media. Major drawback of sequential insertion is the lack of strong security as unauthorized parties could easily intervene with the hidden message. In order to obtain better security, a combination of steganography and cryptography has also become preferential. Thereby in this paper, an enhanced Advance Encryption Standard (AES) cryptography is applied to the message before it is inserted into a cover media. In order to enhance the steganography, each encrypted character is inserted into the cover media by generating highly random positions using Linear Congruential Generator (LCG) method. Experiments were performed by LCG insertion of 1 bit message on each LSB value for the RGB layer. Results obtained showed an average MSE of 0.01 and highest average peak-signal to noise ratio (PSNR) value of 71.00% for the stego images created.