Security System for Safe Transmission of Medical Images

This paper develops an optimised embedding of payload in medical images by using genetic optimisation. The goal is to preserve the region of interest from being distorted because of the watermark. By using this system there is no need to manually define the region of interest by experts as the system will apply the genetic optimisation to select the parts of image that can carry the watermark guaranteeing less distortion. The experimental results assure that genetic based optimisation is useful for performing steganography with less mean square error percentage

Text Hiding in Coded Image Based on Quantization Level Modification and Chaotic Function

A text hiding method in codded image is presented in this paper that based on quantization level modification. The used image is transformed into wavelet domain by DWT and coefficient of transform is partitioned into predefined block size. Specific threshold has been used to classify these blocks into two types named smooth and complex. Each type has its own method of text hiding (binary data), for smooth blocks, secret bits which represent the text data are switched by the bitmap. In order to reduce distortion, the quantization levels are modified. To reach extra embedding payload the quantization level could carry extra two bits depending on other threshold. The complex block carry one data bit on each block and quantization levels are swapped to reduce distortion with bitmap flipping. The proposed method result shows a high signal to noise ratio, with studying capacity as important in this work

High Capacity Audio Steganography Based on Contourlet Transform

The science of hiding information behind other cover media file is known steganography. Audio steganography means that a secret message is hidden by embedding it in an audio file. This paper presents a new audio steganography approach that is used the contourlet transform to hide a speech and image in an audio signal. The cover audio signal is modified to be suitable as input to contourlet transform and then secret data embed to the subbands of contourlet transform. The results showed high hiding capacity of data up to 90% of cover audio file size. In addition, performance analysis by measures factors: Normalized Correlation (NC), Signal to Noise Ratio (SNR) and Peak Signal to Noise Ratio (PSNR) appears good quality results for both stego and secret data

A Review on Steganography Techniques

Steganography is the science of hiding a secret message in cover media, without any perceptual distortion of the cover media. Using steganography, information can be hidden in the carrier items such as images, videos, sounds files, text files, while performing data transmission. In image steganography field, it is a major concern of the researchers how to improve the capacity of hidden data into host image without causing any statistically significant modification. Therefore, this paper presents most of the recent works that have been conducted on image steganography field and analyzes them to clarify the strength and weakness points in each work separately in order to be taken in consideration for future works in such field.