ABSTRACT :
Since several years, the protection of multimedia data is becoming v
ery important. The protection of this multi-
media data can be done with encryption or data hiding algorithms. To dec
rease the transmission time, the data
compression is necessary. Since few years, a new problem is trying
to combine in a single step, compression,
encryption and data hiding. So far, few solutions have been proposed to
combine image encryption and com-
pression for example. Nowadays, a new challenge consists to embed data
in encrypted images. Since the entropy
of encrypted image is maximal, the embedding step, considered like
noise, is not possible by using standard data
hiding algorithms. A new idea is to apply reversible data hiding algor
ithms on encrypted images by wishing
to remove the embedded data before the image decryption. Recent re
versible data hiding methods have been
proposed with high capacity, but these methods are not applicable on enc
rypted images. In this paper we propose
an analysis of the local standard deviation of the marked encrypted images i
n order to remove the embedded
data during the decryption step. We have applied our method on variou
s images, and we show and analyze the
obtained results.
