Existence Of Hidden Information Research Articles

A Novel Technique for Image Steganalysis Based on Separable Convolution and Adversarial Mechanism

Image steganalysis is a technique for detecting the presence of hidden information in images, which has profound significance for maintaining cyberspace security. In recent years, various deep steganalysis networks have been proposed in academia, and have achieved good detection performance. Although convolutional neural networks (CNNs) can effectively extract the features describing the image content, the difficulty lies in extracting the subtle features that describe the existence of hidden information. Considering this concern, this paper introduces separable convolution and adversarial mechanism, and proposes a new network structure that effectively solves the problem. The separable convolution maximizes the residual information by utilizing its channel correlation. The adversarial mechanism makes the generator extract more content features to mislead the discriminator, thus separating more steganographic features. We conducted experiments on BOSSBase1.01 and BOWS2 to detect various adaptive steganography algorithms. The experimental results demonstrate that our method extracts the steganographic features effectively. The separable convolution increases the signal-to-noise ratio, maximizes the channel correlation of residuals, and improves efficiency. The adversarial mechanism can separate more steganographic features, effectively improving the performance. Compared with the traditional steganalysis methods based on deep learning, our method shows obvious improvements in both detection performance and training efficiency.

High capacity image steganography using LSB with modified binary addition on RGB indicator

Steganography is the practice of hiding information in the code that makes up digital files and preventing unwanted people from knowing the existence of hidden information. High-capacity steganography techniques have been successfully performed using LSB with binary addition method, but the quality can be improved using LSB with modified binary addition. By using binary addition, message insertion can be done with two bits at once in one insertion process. For six examples of images, the message insertion process is carried out using the binary addition method and modified binary addition method with the use of 100% capacity or using all pixel values of the image. Then the SSIM, MSE, and PSNR values are calculated from each test result. This study shows that the modified binary addition method has better quality than the binary addition method. The test results show that the binary addition method produces average SSIM, MSE, and PSNR values respectively 0.971743, 9.711678, and 38.26588. Meanwhile, modified binary addition resulted in the values of 0.993287, 2.112745, and 44.88844. These results indicate that the modified binary addition method produces better quality than binary addition while maintaining high message capacity.

An Optimized Hybrid Algorithm for Blind Watermarking Scheme Using Singular Value Decomposition in RDWT-DCT Domain

Watermarking is a technique which offers more robustness and good imperceptibility. Even if the algorithmic principle is public or the existence of hidden information is known, it is difficult to attacker to destroy the embedded watermark without degrading the watermarked media severely. In existence, non-blind watermarking (NBW) schemes and different combinations of techniques are proposed for watermarking procedure. But these methods failed to provide the good imperceptibility, lack of robustness and embedding capacity standards, respectively. Thus, to overcome this problem, a hybrid algorithm for blind watermarking (BW) is proposed, which utilizes redundant discrete wavelet transform (RDWT), discrete cosine transform (DCT) and singular value decomposition (SVD) together to have the advantages of all three. In addition, optimization of proposed RDWT-DCT-SVD is obtained using a new bio-inspired algorithm called Porcellio Scaber algorithm (PSA). Thus, the visual perception of extracted watermark image also good enough by maintaining the robustness against various image attacks. Experiments are carried out to test the proposed BW algorithm and it is successful under various geometrical and non-geometrical attacks. Finally, the performances of proposed BW using RDWT-DCT-SVD with PSA optimization is compared with various existing BW approaches in terms of various quality metrics like peak signal to noise ratio (PSNR), structural similarity (SSIM) index, root mean square error (RMSE) and normalized correlation coefficient (NCC).

4LSB BASED DATA HIDING IN COMPLEX REGION OF DIGITAL IMAGES AND ITS EFFECTS ON EDGES AND HISTOGRAM

Data hiding in the complex regions of cover image make the use of edges for hiding and communicating secret information. The complex region in a digital image is the least sensitive to human visual system (HVS) in term of changes than smooth region. The data hiding in the complex regions affect the edges and the histogram of the image. These two may cause the existence of hidden information to be detected. In this paper, the effect on image edges and histogram is investigated when subjected to true edge based 4 least significant bits (4LSB) steganography. The true edge based 4LSB steganography technique has been found very efficient, creating no significant effect on edges and undetectable histogram differences. Which prove this technique immune to histogram difference steganalysis. The quality of the edges is preserved and a PNSR of greater than 74dB has been observed for different cover images for the true edge based 4LSB steganography. The quality of stego images, edges can been observed qualitatively and it be seen clearly that no significant changes are introduced due to hiding information in edges using the true edge based steganography.

The Agency Theory Approach to the Public Procurement System

This paper combines elements of the agency theory with the practice of the public procurement system in Poland. It defines the concept of the agency relationship, shows its connection with the adverse selection and the moral hazard issue and investigates the nature of the agency generated by the existence of hidden information and hidden action. The main objective of the paper is to build and present a framework for analysing the mechanism of the agency theory in the public procurement system. Keywords: agency theory, public procurement