X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/canny.git/blobdiff_plain/dd86a49a6884ba85ab2469757bbec464943ad7e5..222b1caaf60e918817a332b5ce7774cf792fef59:/ourapproach.tex diff --git a/ourapproach.tex b/ourapproach.tex index 5d16fd0..eeabc98 100644 --- a/ourapproach.tex +++ b/ourapproach.tex @@ -8,7 +8,8 @@ The message extraction is then presented (Sect.~\ref{sub:extract}) and a runnin The flowcharts given in Fig.~\ref{fig:sch} summarize our steganography scheme denoted by -STABYLO, which stands for STeganography with cAnny, Bbs, binarY embedding at LOw cost. +STABYLO, which stands for STeganography with +Adaptive, Bbs, binarY embedding at LOw cost. What follows are successively some details of the inner steps and the flows both inside the embedding stage (Fig.~\ref{fig:sch:emb}) and inside the extraction one (Fig.~\ref{fig:sch:ext}). @@ -147,12 +148,13 @@ This is the classical approach adopted in steganography. Practically, the Canny algorithm generates a set of edge pixels related to a threshold that is decreasing until its cardinality -is sufficient. +is sufficient. Even in this situation, our scheme is adapting +its algorithm to met all the user requirements. - -Two methods may further be applied to select bits that -will be modified. +Once the map of possibly modified pixels is computed, +two methods may further be applied to extract bits that +are really modified. The first one randomly chooses the subset of pixels to modify by applying the BBS PRNG again. This method is further denoted as a \emph{sample}. Once this set is selected, a classical LSB replacement is applied to embed the @@ -369,3 +371,6 @@ This function allows to emphasize differences between contents. \caption{Differences with Lena's cover wrt $b$} \label{fig:lenadiff} \end{figure} + + +