Colour Image Steganography Based on Pixel Value Differencing in Spatial Domain

In a color image every pixel value composed of red, green and blue component and each of which ranges from 0 to 255 in case of 8-bit representation. In this paper, we have used pixel value differencing (PVD) method for secret data embedding in each of the component of a pixel in a color image. But when we use pixel-value differencing (PVD) method as image steganographic scheme, the pixel values in the stegoimage may exceed the range 0~255. We have eliminated this overflow problem of each component pixel. Furthermore for providing more security, we have used different number of bits in different pixel components. It would be very difficult to trace how many bits are embedded in a pixel of the stego image. From the experiments it is seen that the results obtained in proposed method provides better visual quality of stego-image compared to the PVD method.