1 Published By: Blue Eyes Intelligence Engineering

Abstract – Steganography hides the existence of secret information rather than hiding its meaning only. The main aim of steganography is to increase the steganographic capacity and enhance the imperceptibility or undetectability. However, steganographic capacity and imperceptibility are at odds with each other. It is not possible to simultaneously maximize the security and capacity of a steganographic system. Increasing steganographic capacity and enhancing stego image quality are still challenges. Since peak signal-to-noise ratio (PSNR) is extensively used as a quality measure of stego images, the reliability of PSNR for stego images is evaluated in the work described. The proposed work is compared with the existing method using PSNR, NCC, SC as comparison parameters. Proposed technique reduces the requirement to keep record of cover images for secret information extraction. Otherwise for each information received, the receiver should also have the cover image saved with him, which he should recall everytime for each information extraction. Proposed technique is used for the extraction of secret information for which cover image has to be recovered by noise removal methods. In the proposed technique I have tried to obtain the secret image from stego image without having cover image. Soft thresholding and bilateral filtering are the methods used to obtain cover image. Experimental results shows that there’s a trade – off between stego image and secret image extracted. It is seen that as we increase the value of alpha, stego image degrades, but secret image improves. The secret image obtained is in visually acceptable form. Results shown are objective and subjective in nature