Spread Embedding Technique in LSB Image Steganography based on Chaos Theory

Abstract

Spread spectrum technique is one way to increase the security and imperceptibility of messages embedded in stego images. The way this method works is by embedding it spreadly and randomly to all images with certain random patterns. Generally, random patterns are implemented using modulation and PN sequence generators. In this research, spread spectrum embedding techniques are implemented with chaotic encryption. Generally, chaotic encryption is done on the message image, but in this research, chaos encryption is applied to the cover image with the aim of spreading the message. Chaos encryption is chosen because this method only randomizes pixel coordinates without changing pixel values. In this way, the message embedding on the smallest bit of the cover image is carried out in a spread with chaotic patterns so that the attacker is not easily guessed. Chaotic patterns will be formed from the Arnold chaotic map formula with parameters determined from password processing, the goal being that patterns are formed more dynamically. In addition, during the embedding process, the message is encrypted with the XOR operation based on the MSB value. Based on testing the proposed method proved to be safer and slightly more imperceptible compared to the previous method.