Informatica

Many confidential multimedia, such as personal privacy, commercial, and military secrets, are transmitted on the Internet. To prevent this confidential multimedia from being eavesdropped on by illegal users, information-hiding technology is a leading research topic nowadays. One of the important research topics of information-hiding technology is coverless information hiding, which utilizes the unchanged property of its multimedia carrier to hide secret information. In this paper, we propose two schemes that employ the average pixel value of an image. The first is an extension of the Coverless Information Hiding Based on the Most Significant Bit (CIHMSB) scheme, referred to as E-CIHMSB. In the E-CIHMSB, we build an extended matrix containing the image fragment’s average pixel value. The second scheme is a combination theory-based CIHMSB, referred to as CB-CIHMSB. In the CB-CIHMSB, we construct the combined matrix. E-CIHMSB and CB-CIHMSB embed the secret bits by changing the most significant bits of the chosen pixel in the matrix. Experimental results show that our schemes achieved higher hiding capacity than previous related schemes. Moreover, the proposed scheme is more robust against steganalysis tools and image quality attacks such as Additive Gaussian White Noise (AWGN), Salt & Pepper noise, low-pass filtering attacks, and JPEG compression attacks than CIHMSB.

An Unequal Error Protection (UEP) scheme for image steganography is proposed in this paper. When stego images are transmitted through a noisy channel, the embedded message may be more sensitive to noise than the cover message. Therefore, we propose a Turbo UEP coding scheme for steganographic communication in a noisy channel, which provides higher error protection for the embedded message and lower error protection for the cover message. Simulations show that this coding scheme provides different error protection levels in one coding process and maintains the coding rate constant. In addition, an application scheme of the proposed Turbo UEP code for steganographic communication is presented, and the experimental results show that the extracted secret images have better quality than the cover images after decoding.