Variable Rate Steganography in Digital Images Using Two, Three and Four Neighbor Pixels

In this paper three image steganography methods with variable rate of embedding are proposed. In the first method, called two neighbor method the two neighboring pixels such as upper and left are exploited to take embedding decisions. In three neighbor method the three neighboring pixels such as upper, left and right are exploited to take embedding decisions. In four neighbor method the four neighboring pixels such as upper, left, right and bottom are exploited to take embedding decisions. The message extraction process is very simple and does not require any knowledge of the original image. The experimental results show that the distortion is less in two neighbor method as compared to the other two methods. But the theoretical studies reveal that the capacity in four neighbor method is more as compared to two and three neighbor methods.