Distributed Steganography Using Five Pixel Pair Differencing and Modulus Function

FPPD steganography is one of steganography techniques that hides secret message by adjusting the difference between pixel pairs in 2x3 blocks. FPPD usually deals with using one cover image to hide any data. To make it practical, a steganography method needs to accommodate concatenated data of different types of media. The steganography method should also allow large data to be distributed on multiple cover images. Therefore, there should be indicator for the start, end, and media type of each component of secret data. The purpose of this research is to develop a FPPD based distributed steganography which allow addition of multiple secret message components across multiple cover images while informing the recipient of the media type of each secret message. This is done by applying a modulus function to to adjust the values of a block to represent the start, end, continuation, and media type of secret messages. The proposed approach results in PSNR value of 37.62, below the benchmark FPPD method. This decrease in PSNR is the result of modification to the pixel value of the reference point to provide means to embed data of different media types into several images.