  A steganographic method based on the chaotic fractional map and in the DCT
domain is proposed. This method embeds a secret message in some high frequency
coefficients of the image using a 128-bit private key and a chaotic fractional
map which generate a permutation indicating the positions where the secret bits
will be embedded. An experimental work on the validation of the proposed method
is also presented, showing performance in imperceptibility, quality, similarity
and security analysis of the steganographic system. The proposed algorithm
improved the level of imperceptibility and Cachin's security of stego-system
analyzed through the values of Peak Signal-to-Noise Ratio (PSNR) and the
Relative Entropy (RE).
