  An efficient 2-step steganography technique is proposed to enhance stego
image quality and secret message un-detectability. The first step is a
preprocessing algorithm that reduces the size of secret images without losing
information. This results in improved stego image quality compared to other
existing image steganography methods. The proposed secret image size reduction
(SISR) algorithm is an efficient spatial domain technique. The second step is
an embedding mechanism that relies on Fibonacci representation of pixel
intensities to minimize the effect of embedding on the stego image quality. The
improvement is attained by using bit-plane(s) mapping instead of bit-plane(s)
replacement for embedding. The proposed embedding mechanism outperforms the
binary based LSB randomly embedding in two ways: reduced effect on stego
quality and increased robustness against statistical steganalysers.
Experimental results demonstrate the benefits of the proposed scheme in terms
of: 1) SISR ratio (indirectly results in increased capacity); 2) quality of the
stego; and 3) robustness against steganalysers such as RS, and WS. Furthermore,
experimental results show that the proposed SISR algorithm can be extended to
be applicable on DICOM standard medical images. Future security standardization
research is proposed that would focus on evaluating the security, performance,
and effectiveness of steganography algorithms.
