Increasing the Capacity of Listega Based on Syllable Pattern Using Multicolumn and Bigram Mapping

Abstract

Due to the increasing use of internet, preserving confidentiality and integrity becomes important. One method for preserving them is steganography. There are two types of steganography, noisy and noiseless. One of noiseless steganography method is List Steganography based on syllable pattern proposed by David et al. Since List Steganography based on syllable pattern only embed one character into one column, then the capacity is still low. For increasing the capacity, the proposed method introduced embedding method for two columns where one column can be embedded with up to two characters (one bigram). The characters are embedded based on the syllable and code mapping. Syllable mapping is designed based on the occurrence frequency of syllable in the cover and English dictionary, while code mapping is designed based on the occurrence frequency of the code in the cover. Based on the experiment result, the embedding capacity using English secret message is increased with the rate of 17% to 55%.