Two new steganography techniques based on quotient value differencing with addition-subtraction logic and PVD with modulus function

This paper proposes two steganography techniques, (i) quotient value differencing (QVD), and (ii) pixel value differencing with modulus function (MFPVD). The QVD technique operates on 3 x 3 size non-overlapped pixel blocks. In every pixel of a block LSB substitution is applied on 2 LSBs and the remaining 6 bits forms a quotient block. In the quotient block, QVD embedding approach is applied by exploiting the edges in eight directions. The MFPVD technique uses 2 x 3 size non-overlapped pixel blocks to exploit the edges in five directions. One of the pixels is termed as the central pixel. By considering this central pixel as a reference value, five difference values with five neighboring pixels are calculated. Based on the average of these five difference values, the hiding capacity in all the five directions is decided. As compared to the existing techniques, the proposed QVD technique possesses higher hiding capacity and the proposed MFPVD technique possesses higher peak signal-to-noise ratio (PSNR). Furthermore, the proposed techniques are undetectable by RS analysis and pixel difference histogram (PDH) analysis.