Abstract

This paper proposes a method for image steganography. According to Human Visual System, any variation in the edges shown in the images has a low probability of being perceived by the human eyes, thus data can be hidden in the pixel of the cover image. These edges can be detected by using sophisticated operators like Canny edge detection operator. The gradient of the pixel of the image is determined and the image edges are detected by taking a threshold value of the gradient image. Here we go for multiple edge detection so that more number of pixels around the edge area is detected using the above method. Thus resulting in embedding of more information bits in the LSB of the image pixels further again we go for variable embedding so the combination of multiple edge detection and variable embedding improves the data hiding capacity. The multiple edge detection is limited to three times so as to reduce the distortions. To further increase the data hiding capacity and at the same time maintain a respectable PSNR variable embedding method is employed. For extraction of data the stego image is compared with the cover image, and the variation in the pixel values are detected, thus the embedded data is efficiently extracted.

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