Cryptography Reference
In-Depth Information
Fig. 8.11.
LSB plane of the image with secret data embedded by the proposed
method.
other words, we are unable to distinguish between the LSB of the cover image
and that of the stego-image.
The proposed method decreases 1 bit of hiding data capacity for blocks
whose complexity is less than α
TH
or greater than 1−α
TH
.Ifα
TH
is getting
close to 0, then the number of blocks we need to apply conjugate operation
decreases. In such cases, the proposed method is useless because conjugation
flags are not needed in extracting embedded information. However, image
degradation will occur on the image data as detectable patterns. Moreover,
by the comparison between bit-planes, one can easily recognize the existence
of embedded information. Therefore, the proposed method is very effective,
that is secure, when we embed secret data with keeping high image quality
by using BPCS.
8.4.4 Conclusion
We have presented an improved BPCS steganography that removes an iden-
tifying signature that can be found in conventional BPCS steganography.
The proposed method can embed both secret data and the conjugation flags
into cover images with image segmentation using the complexity threshold-
ing, therefore, unnatural patterns which can be used as the signature do not
appear in the stego-images.
8.5 Application of BPCS Steganography to JPEG2000
Encoded Images
BPCS steganography is not robust with respect to lossy compression of
dummy image, as are all other bit-plane-based steganography methods. To
deploy the merits of BPCS steganography technique, in a practical scenario
