Popis: |
In most steganographic methods, increasing in the capacity leads to decrease in the quality of the stego-image, so in this paper, we propose to combine two existing techniques, Pixel value differencing and Gray Level Modification, to come up with a hybrid steganography scheme which can hide more information without having to compromise much on the quality of the stego-image. Experimental results demonstrate that the proposed approach has larger capacity while its results are imperceptible. In comparison with original PVD method criterion of the quality is declined by 2% dB averagely while the capacity is increased around 25%. |