Information secured by the guidance of salt and pepper noise

Abstract

Steganography is the information hiding technique; here the secret data is embedded into the carrier medium. Usually carrier medium is image, audio or video. In this paper image is used as the carrier medium referred as cover image and text data is embedded into this, after embedding it is referred as stego image. In an existing spatial domain approaches different methods such as pixel indicator, random bit embedding, Zigzag embedding techniques etc are used. On all these techniques data is embedded into the least significant bits (LSB) of every pixel, because it reduces the difference between the cover image and stego image instead of embedding into the MSBs. In our proposed approach, secret data is embedded into the LSBs of cover image as like existing. But instead of present available techniques, salt & pepper noise is used to guide the embedding positions of secret data. Salt & Pepper noise is added into the copy of cover image at defined density and it is referred as reference image. The added portion of salt changes the pixel values into zero and Pepper changes the pixel values into maximum intensity value. Based on the changes in reference image, different bit of secret data is embedding into the corresponding pixels of cover image. The performance of this technique is analyzed by using PSNR, MSE performance metrics.