## 4 Experimental Results and Analysis
### Performance Comparison  
In the frame-wise steganalysis task, the goal is to detect whether individual speech frames contain secret information. This means that rather than considering the entire speech  
Figure 5: Detection accuracies for different depths of the deep residual network across the three steganography datasets. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Type of Bilinear Interaction**} & \multicolumn{3}{c}{**Steganography Methods**} \\ \cline{2-4}  & **CNV** & **ACL** & **HPS** \\ \hline Field-All & 0.7407 & 0.8654 & 0.7635 \\ Field-Each & 0.7419 & 0.8675 & 0.7651 \\ Field-Interaction & 0.7446 & 0.8692 & 0.7664 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Detection Accuracy of the Methods Using Three Types of Bilinear Interaction. signal or examining speech lengths, the focus is on analyzing each frame independently. The embedding rate in steganography is a parameter that represents the proportion of secret information embedded within the carrier signal (in this case, speech frames). By evaluating detection performance at different embedding rates (ranging from 20% to 100% at 20% intervals), we assessed how well the steganalysis methods performed in detecting hidden information across various levels of embedding. Tables 4-6 show the experimental results. Based on the information provided in Tables 4-6, our method achieved the highest detection accuracy among the four steganalysis methods. Specifically, for the ACL steganography method [17], when the embedding rate was 100%, our method achieved an accuracy of 86.92%, while the accuracies of the other methods (DMSM [31], FSMDP [33], and Stegaformer [34]) were 85.48%, 85.90%, and 86.04%, respectively. For the HPS steganography method [21], when the embedding rate was 100%, our method achieved an accuracy of 76.64%. In comparison, the accuracies of the other three methods (DMSM [31], FSMDP [33], and Stegaformer [34]) were 74.04%, 74.21%, and 74.54%, respectively. In addition, it can be observed that the detection accuracy increased with higher embedding rates. This trend arises because a higher embedding rate corresponds to a larger capacity for concealing secret information in speech frames. The perceptual quality of steganographic speech is closely linked to its detectability. Embedding secret data inevitably introduces subtle distortions, which degrade the perceptual quality of steganographic speech and, in turn, make it more vulnerable to steganalysis. As analyzed in a previous study [17], both the embedding rate and bitrate significantly influence the perceptual quality of steganographic speech, and lower perceptual quality generally leads to higher detection accuracy. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Steganalysis Method**} & \multicolumn{5}{c}{**Embedding Rate**} \\ \cline{2-6}  & **20\%** & **40\%** & **60\%** & **80\%** & **100\%** \\ \hline DMSM & 0.5451 & 0.6076 & 0.6614 & 0.6976 & 0.7404 \\ FSMDP & 0.5475 & 0.6110 & 0.6633 & 0.7013 & 0.7421 \\ Stegformer & 0.5502 & 0.6123 & 0.6680 & 0.7022 & 0.7454 \\ Our method & **0.5590** & **0.6285** & **0.6814** & **0.7178** & **0.7664** \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Detection accuracy for the HPS steganography method. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Steganalysis Method**} & \multicolumn{5}{c}{**Embedding Rate**} \\ \cline{2-6}  & **20\%** & **40\%** & **60\%** & **80\%** & **100\%** \\ \hline DMSM & 0.5231 & 0.5806 & 0.6214 & 0.6609 & 0.7208 \\ FSMDP & 0.5252 & 0.5725 & 0.6303 & 0.6649 & 0.7220 \\ Stegformer & 0.5375 & 0.5895 & 0.6426 & 0.6779 & 0.7232 \\ Our method & **0.5529** & **0.6106** & **0.6615** & **0.7052** & **0.7446** \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Detection accuracy for the CNV steganography method.