X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/canny.git/blobdiff_plain/b04e55fbbcdcbca04098f1bf05ec4473e47b5c51..refs/heads/master:/experiments.tex diff --git a/experiments.tex b/experiments.tex index 6660072..aa49e84 100644 --- a/experiments.tex +++ b/experiments.tex @@ -1,3 +1,5 @@ +First of all, the whole code of STABYLO can be downloaded +\footnote{\url{http://http://members.femto-st.fr/jf-couchot/en/stabylo}}. For all the experiments, the whole set of 10,000 images of the BOSS contest~\cite{Boss10} database is taken. In this set, each cover is a $512\times 512$ @@ -10,7 +12,7 @@ We use the matrices $\hat{H}$ generated by the integers given in Table~\ref{table:matrices:H} as introduced in~\cite{FillerJF11}, since these ones have experimentally -be proven to have the best modification efficiency. +be proven to have the strongest modification efficiency. For instance if the rate between the size of the message and the size of the cover vector is 1/4, each number in $\{81, 95, 107, 121\}$ is translated into a binary number @@ -40,116 +42,100 @@ $$ \hline \end{array} $$ -\caption{Matrix Generator for $\hat{H}$ in STC}\label{table:matrices:H} +\caption{Matrix Generator for $\hat{H}$ in STC.}\label{table:matrices:H} \end{table} -Our approach is always compared to Hugo~\cite{DBLP:conf/ih/PevnyFB10} -and to EAISLSBMR~\cite{Luo:2010:EAI:1824719.1824720}. -The former is the least detectable information hiding tool in spatial domain -and the latter is the work that is the closest to ours, as far as we know. - - - -First of all, in our experiments and with the adaptive scheme, -the average size of the message that can be embedded is 16,445 bits. -It corresponds to an average payload of 6.35\%. -The two other tools will then be compared with this payload. -Sections~\ref{sub:quality} and~\ref{sub:steg} respectively present -the quality analysis and the security of our scheme. +Our approach is always compared to HUGO, to EAISLSBMR, to WOW and to UNIWARD +for the two strategies Fixed and Adaptive. +For the former one, the payload has been set to 10\%. +For the latter one, the Canny parameter $T$ has been set to 3. +When $b$ is 7, the average size of the message that can be embedded +is 16,445 bits, +that corresponds to an average payload of 6.35\%. +For each cover image the STABYLO's embedding rate with these two parameters +is memorized. +Next each steganographic scheme is executed to produce the stego content of +this cover with respect to this embedding rate. -\subsection{Image quality}\label{sub:quality} -The visual quality of the STABYLO scheme is evaluated in this section. -For the sake of completeness, three metrics are computed in these experiments: -the Peak Signal to Noise Ratio (PSNR), -the PSNR-HVS-M family~\cite{psnrhvsm11}, -%the BIQI~\cite{MB10}, -and -the weighted PSNR (wPSNR)~\cite{DBLP:conf/ih/PereiraVMMP01}. -The first one is widely used but does not take into -account the Human Visual System (HVS). -The other ones have been designed to tackle this problem. - -If we apply them on the running example, -the PSNR, PSNR-HVS-M, and wPSNR values are respectively equal to -68.39, 79.85, and 89.71 for the stego Lena when $b$ is equal to 7. -If $b$ is 6, these values are respectively equal to -65.43, 77.2, and 89.35. +% \subsection{Image quality}\label{sub:quality} +% The visual quality of the STABYLO scheme is evaluated in this section. +% For the sake of completeness, three metrics are computed in these experiments: +% the Peak Signal to Noise Ratio (PSNR), +% the PSNR-HVS-M family~\cite{psnrhvsm11}, +% and +% the weighted PSNR (wPSNR)~\cite{DBLP:conf/ih/PereiraVMMP01}. +% The first one is widely used but does not take into +% account the Human Visual System (HVS). +% The other ones have been designed to tackle this problem. +% If we apply them on the running example with the Adaptive and STC strategies, +% the PSNR, PSNR-HVS-M, and wPSNR values are respectively equal to +% 68.39, 79.85, and 89.71 for the stego Lena when $b$ is equal to 7. +% If $b$ is 6, these values are respectively equal to +% 65.43, 77.2, and 89.35. -\begin{table*} -\begin{center} -\begin{small} -\begin{tabular}{|c|c|c||c|c|c|c|c|c|c|c|c|c|} -\hline -Schemes & \multicolumn{4}{|c|}{STABYLO} & \multicolumn{2}{|c|}{HUGO}& \multicolumn{2}{|c|}{EAISLSBMR} & \multicolumn{2}{|c|}{WOW} & \multicolumn{2}{|c|}{UNIWARD}\\ -\hline -Embedding & Fixed & \multicolumn{3}{|c|}{Adaptive (about 6.35\%)} & Fixed &Adaptive & Fixed &Adaptive & Fixed &Adaptive & Fixed &Adaptive \\ -\hline -Rate & 10\% & + sample & +STC(7) & +STC(6) & 10\%&6.35\%& 10\%&6.35\%& 10\%&6.35\%& 10\%&6.35\%\\ -\hline -PSNR & 61.86 & 63.48 & 66.55 (\textbf{-0.8\%}) & 63.7 & 64.65 & {67.08} & 60.8 & 62.9&65.9 & 68.3 & 65.8 & 69.2\\ -\hline -PSNR-HVS-M & 72.9 & 75.39 & 78.6 (\textbf{-0.8\%}) & 75.5 & 76.67 & {79.23} & 71.8 & 74.3\\ -%\hline -%BIQI & 28.3 & 28.28 & 28.4 & 28.28 & 28.28 & 28.2 & 28.2\\ -\hline -wPSNR & 77.47 & 80.59 & 86.43(\textbf{-1.6\%})& 86.28 & 83.03 & {88.6} & 76.7 & 83& 83.8 & 90.4 & 85.2 & 91.9\\ -\hline -\end{tabular} -\end{small} -\begin{footnotesize} -\vspace{2em} -Variances given in bold font express the quality differences between -HUGO and STABYLO with STC+adaptive parameters. -\end{footnotesize} -\end{center} -\caption{Quality measures of steganography approaches\label{table:quality}} -\end{table*} +% \begin{table*} +% \begin{center} +% \begin{small} +% \setlength{\tabcolsep}{3pt} +% \begin{tabular}{|c|c|c||c|c|c|c|c|c|c|c|c|c|} +% \hline +% Schemes & \multicolumn{4}{|c|}{STABYLO} & \multicolumn{2}{|c|}{HUGO}& \multicolumn{2}{|c|}{EAISLSBMR} & \multicolumn{2}{|c|}{WOW} & \multicolumn{2}{|c|}{UNIWARD}\\ +% \hline +% Embedding & Fixed & \multicolumn{3}{|c|}{Adaptive (about 6.35\%)} & Fixed &Adaptive & Fixed &Adaptive & Fixed &Adaptive & Fixed &Adaptive \\ +% \hline +% Rate & 10\% & + sample & +STC(7) & +STC(6) & 10\%&$\approx$6.35\%& 10\%&$\approx$6.35\%& 10\%&$\approx$6.35\%& 10\%&$\approx$6.35\%\\ +% \hline +% PSNR & 61.86 & 63.48 & 66.55 & 63.7 & 64.65 & {67.08} & 60.8 & 62.9&65.9 & 68.3 & 65.8 & 69.2\\ +% \hline +% PSNR-HVS-M & 72.9 & 75.39 & 78.6 & 75.5 & 76.67 & {79.6} & 71.8 & 76.0 & +% 76.7 & 80.35 & 77.6 & 81.2 \\ +% \hline +% wPSNR & 77.47 & 80.59 & 86.43& 86.28 & 83.03 & {88.6} & 76.7 & 83& 83.8 & 90.4 & 85.2 & 91.9\\ +% \hline +% \end{tabular} +% \end{small} +% \end{center} +% \caption{Quality measures of steganography approaches\label{table:quality}} +% \end{table*} -Results are summarized in Table~\ref{table:quality}. -Let us give an interpretation of these experiments. -First of all, the adaptive strategy produces images with lower distortion -than the images resulting from the 10\% fixed strategy. -Numerical results are indeed always greater for the former strategy than -for the latter one. -These results are not surprising since the adaptive strategy aims at -embedding messages whose length is decided according to an higher threshold -into the edge detection. -Let us focus on the quality of HUGO images: with a given fixed -embedding rate (10\%), -HUGO always produces images whose quality is higher than the STABYLO's one. -However our approach is always better than EAISLSBMR since this one may modify -the two least significant bits. +% Results are summarized in Table~\ref{table:quality}. +% In this table, STC(7) stands for embedding data in the LSB whereas +% in STC(6), data are hidden in the last two significant bits. -If we combine \emph{adaptive} and \emph{STC} strategies -(which leads to an average embedding rate equal to 6.35\%) -our approach provides metrics equivalent to those provided by HUGO. -In this column STC(7) stands for embedding data in the LSB whereas -in STC(6), data are hidden in the last two significant bits. +% Let us give an interpretation of these experiments. +% First of all, the Adaptive strategy produces images with lower distortion +% than the images resulting from the 10\% fixed strategy. +% Numerical results are indeed always greater for the former strategy than +% for the latter one. +% These results are not surprising since the Adaptive strategy aims at +% embedding messages whose length is decided according to a higher threshold +% into the edge detection. -The quality variance between HUGO and STABYLO for these parameters -is given in bold font. It is always close to 1\% which confirms -the objective presented in the motivations: -providing an efficient steganography approach in a lightweight manner. +% If we combine Adaptive and STC strategies +% the STABYLO scheme provides images whose quality is higher than +% the EAISLSBMR's one but lower than the quality of high complexity +% schemes. Notice that the quality of the less respectful scheme (EAILSBMR) +% is lower than 6\% than the one of the most one. -Let us now compare the STABYLO approach with other edge based steganography -approaches, namely~\cite{DBLP:journals/eswa/ChenCL10,Chang20101286}. -These two schemes focus on increasing the -payload while the PSNR is acceptable, but do not -give quality metrics for fixed embedding rates from a large base of images. +% % Let us now compare the STABYLO approach with other edge based steganography +% % approaches, namely~\cite{DBLP:journals/eswa/ChenCL10,Chang20101286}. +% % These two schemes focus on increasing the +% % payload while the PSNR is acceptable, but do not +% % give quality metrics for fixed embedding rates from a large base of images. @@ -162,9 +148,20 @@ The steganalysis quality of our approach has been evaluated through the % two % AUMP~\cite{Fillatre:2012:ASL:2333143.2333587} % and Ensemble Classifier~\cite{DBLP:journals/tifs/KodovskyFH12} based steganalyser. -This approach aims at detecting hidden bits in grayscale natural -images and is -considered as state of the art steganalysers in the spatial domain~\cite{FK12}. +Its particularization to spatial domain is +considered as state of the art steganalysers. +Features that are embedded into this steganalysis process +are CCPEV and SPAM features as described +in~\cite{DBLP:dblp_conf/mediaforensics/KodovskyPF10}. +They are extracted from the +set of cover images and the set of training images. +Next a small +set of weak classifiers is randomly built, +each one working on a subspace of all the features. +The final classifier is constructed by a majority voting +between the decisions of these individual classifiers. + + %The former approach is based on a simplified parametric model of natural images. % Parameters are firstly estimated and an adaptive Asymptotically Uniformly Most Powerful % (AUMP) test is designed (theoretically and practically), to check whether @@ -179,13 +176,14 @@ considered as state of the art steganalysers in the spatial domain~\cite{FK12}. \begin{table*} \begin{center} \begin{small} +\setlength{\tabcolsep}{3pt} \begin{tabular}{|c|c|c|c|c|c|c|c|c|c|c|c|c|} \hline Schemes & \multicolumn{4}{|c|}{STABYLO} & \multicolumn{2}{|c|}{HUGO}& \multicolumn{2}{|c|}{EAISLSBMR} & \multicolumn{2}{|c|}{WOW} & \multicolumn{2}{|c|}{UNIWARD}\\ \hline Embedding & Fixed & \multicolumn{3}{|c|}{Adaptive (about 6.35\%)} & Fixed & Adapt. & Fixed & Adapt. & Fixed & Adapt. & Fixed & Adapt. \\ \hline -Rate & 10\% & + sample & +STC(7) & +STC(6) & 10\%& 6.35\%& 10\%& 6.35\% & 10\%& 6.35\%& 10\%& 6.35\%\\ +Rate & 10\% & + sample & +STC(7) & +STC(6) & 10\%& $\approx$6.35\%& 10\%& $\approx$6.35\% & 10\%& $\approx$6.35\%& 10\%& $\approx$6.35\%\\ \hline %AUMP & 0.22 & 0.33 & 0.39 & 0.45 & 0.50 & 0.50 & 0.49 & 0.50 \\ %\hline @@ -195,24 +193,44 @@ Ensemble Classifier & 0.35 & 0.44 & 0.47 & 0.47 & 0.48 & 0.49 & 0.43 & 0 \end{tabular} \end{small} \end{center} -\caption{Steganalysing STABYLO\label{table:steganalyse}} +\caption{Steganalysing STABYLO\label{table:steganalyse}.} \end{table*} -Results are summarized in Table~\ref{table:steganalyse}. +Results of average testing errors +are summarized in Table~\ref{table:steganalyse}. First of all, STC outperforms the sample strategy %for % the two steganalysers as already noticed in the quality analysis presented in the previous section. -Next, our approach is more easily detectable than HUGO, which -is the most secure steganographic tool, as far as we know. -However by combining \emph{adaptive} and \emph{STC} strategies -our approach obtains similar results to HUGO ones. - -%%%%et pour b= 6 ? - - -Compared to EAILSBMR, we obtain better results when the strategy is -\emph{adaptive}. -However due to its -huge number of integration features, it is not lightweight, which justifies -in the authors' opinion the consideration of the proposed method. +Next, our approach is more easily detectable than HUGO, +WOW and UNIWARD which are the most secure steganographic tool, +as far as we know. +However by combining Adaptive and STC strategies +our approach obtains similar results than the ones of these schemes. + +Compared to EAILSBMR, we obtain similar +results when the strategy is +Adaptive. +However due to its huge number of integration features, it is not lightweight. + +All these numerical experiments confirm +the objective presented in the motivations: +providing an efficient steganography approach in a lightweight manner +for small payload. + +In Figure~\ref{fig:error}, +Ensemble Classifier has been used with all the previous +steganographic schemes with 4 different payloads. +It can be observed that face to high values of payload, +STABYLO is definitely not secure enough. +However thanks to an efficient very low-complexity (Fig.\ref{fig:compared}), +we argue that the user should embed tiny messages in many images +than a larger message in only one image. +\begin{figure} +\begin{center} +\includegraphics[scale=0.5]{error} +\end{center} +\caption{Testing errors obtained by Ensemble classifier with +WOW/UNIWARD, HUGO, and STABYLO w.r.t. payload.} +\label{fig:error} +\end{figure}