Adaptive Matrix Pattern Steganography on RGB Images

Almost all spatial domain image steganography methods rely on modifying the Least Significant Bits (LSB) of each pixel to minimize the visual distortions. However, these methods are susceptible to LSB blind attacks and quantitative steganalyses. This paper presents an adaptive spatial domain image steganography algorithm for hiding digital media based on matrix patterns, named “Adaptive Matrix Pattern” (AMP). The AMP method increases the security of the steganography scheme of largely hidden messages since it adaptively generates a unique codebook matrix pattern for each ASCII character in each image block. Therefore, each ASCII character gets a different codebook matrix pattern even in different regions of the same image. Moreover, it uses a preprocessing algorithm to identify the most suitable image blocks for hiding purposes. The resulting stego-images are robust against LSB blind attacks since the middle bits of green and blue channels generate matrix patterns and hiding secrets, respectively. Experimental results show that AMP is robust against quantitative steganalyses. Additionally, the quality of stego-images, based on the peak signal-to-noise ratio metric, remains high in both stego-RGB-image and in the stego-blue-channel. Finally, the AMP method provides a high hiding capacity, up to 1.33 bits per pixel.

PENGAMANAN IMAGE DENGAN MODIFIKASI ALGORITMA ELECTRONIC CODE BOOK (ECB)

Cryptography is knowledge of encoding data to ensure the confidentiality, security, validity and integrity of data. Cryptography is divided into two namely classical cryptography and modern cryptography. One example of modern cryptography is the Electronic Code Book (ECB). Electronic Code Book (ECB) is a modern cryptographic method used to encrypt and decrypt text, images and more. The image is formed from several pixels which consist of several bits in a pixel. Bits are divided into two namely Least Significant Bit (LSB) and Most Significant Bit (MSB).LSB is the four rightmost bits while MSB is the leftmost four bits of a pixel. The purpose of this study is to compare the level of security of Electronic Code Book (ECB) image security results with the results of securing an Electronic Code Book (ECB) modified image. The data used in this study are 8 RGB and Greyscale images also a key in the form of one ASCII character. The results obtained show that securing images with modified Electronic Code Book (ECB) is safer than securing images with Electronic Code Book (ECB) based on histogram analysis, differential analysis and correlation coefficients. Keywords: ASCII, Electronic Code Book (ECB), Most Significant Bit (MSB)