Adaptive PVD Steganography Using Horizontal, Vertical, and Diagonal Edges in Six-Pixel Blocks

Anita Pradhan,K Raja Sekhar,Gandharba Swain

doi:10.1155/2017/1924618

Anita Pradhan, K Raja Sekhar + Show 1 more

Open Access

https://doi.org/10.1155/2017/1924618

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Abstract

The traditional pixel value differencing (PVD) steganographical schemes are easily detected by pixel difference histogram (PDH) analysis. This problem could be addressed by adding two tricks: (i) utilizing horizontal, vertical, and diagonal edges and (ii) using adaptive quantization ranges. This paper presents an adaptive PVD technique using 6-pixel blocks. There are two variants. The proposed adaptive PVD for 2×3-pixel blocks is known as variant 1, and the proposed adaptive PVD for 3×2-pixel blocks is known as variant 2. For every block in variant 1, the four corner pixels are used to hide data bits using the middle column pixels for detecting the horizontal and diagonal edges. Similarly, for every block in variant 2, the four corner pixels are used to hide data bits using the middle row pixels for detecting the vertical and diagonal edges. The quantization ranges are adaptive and are calculated using the correlation of the two middle column/row pixels with the four corner pixels. The technique performs better as compared to the existing adaptive PVD techniques by possessing higher hiding capacity and lesser distortion. Furthermore, it has been proven that the PDH steganalysis and RS steganalysis cannot detect this proposed technique.

Highlights

In image steganography techniques, the images are used for covert communication [1]
Least significant bit (LSB) substitution methods are the age-old methods of image steganography, wherein the LSB bits of a pixel are substituted by secret data bits
To achieve higher embedding capacity, Swain [8] proposed pixel value differencing (PVD) steganography considering the maximum difference out of all the differences calculated with all the neighbors

Summary

Introduction

The images are used for covert communication [1]. Since we hide the artificial message inside an image, the image statistics change, so the goal is to minimize this change [2]. They proposed pixel value differencing (PVD) steganography. The difference between the two pixels is computed and changed to a new value by hiding data in it.

Results

Conclusion