## 5 Experimental Results
### Performance Comparison between the Proposed Method and Baseline Approaches
#### 5.1.2 Embedding Capability in Different Embedding Capacities  
In this section, the variations in image quality under different embedding capacities between the proposed method and the methods of [PERSON] et al. [46], [PERSON] et al. [47], [PERSON] et al. [21], and [PERSON] et al. [5] are compared. The image quality comparison for six test images in different embedding capacities between the proposed method and the other schemes are shown in Tables 11-13. In addition, the performance comparisons between the proposed method and other related researches are shown in Figure 8 as line graphs. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Image** & **[PERSON] et al.** & **[PERSON] et al.** & **[PERSON] et al.** & **[PERSON] et al.** & **Our Method** \\ \hline Lena & 53.70 & 51.72 & 51.60 & 62.16 & **48.64** \\ Baboon & 51.96 & 51.35 & 51.34 & 70.84 & **48.26** \\ Boat & 51.97 & 51.52 & 51.47 & 66.26 & **48.41** \\ Peppers & 52.49 & 51.60 & 51.51 & 65.92 & **48.39** \\ Airpplain (F-16) & 54.21 & 52.16 & 51.90 & 58.27 & **48.75** \\ House & 53.91 & 52.14 & 51.83 & 58.86 & **48.84** \\ \hline Average & 53.04 & 51.75 & 51.07 & 63.72 & **48.55** \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Comparison of PSNR (dB) between the proposed method and the methods of [PERSON] et al. [46], [PERSON] et al. [47], [PERSON] et al. [21], and [PERSON] et al. [5] for maximum embedding capacity. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Image** & **[PERSON] et al.** & **[PERSON] et al.** & **[PERSON] et al.** & **[PERSON] et al.** & **Our Method** \\ \hline Lena & 2785 & 10,139 & 24,255 & 7964 & **59,751** \\ Baboon & 2717 & 4069 & 9885 & 990 & **19,136** \\ Boat & 5796 & 7193 & 17,295 & 2923 & **37,938** \\ Peppers & 2753 & 8591 & 19,687 & 3040 & **35,402** \\ Airpplain (F-16) & 8155 & 15,797 & 39,843 & 21,300 & **66,465** \\ House & 7336 & 12,585 & 36,710 & 20,448 & **71,373** \\ \hline Average & 4923.67 & 9729.00 & 24,612.50 & 9444.17 & **48,344.17** \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Comparison of maximum embedding capacity (bits) for six test images between the proposed method and the methods of [PERSON] et al. [46], [PERSON] et al. [47], [PERSON] et al. [21], and [PERSON] et al. [5]. Figure 8: Performance comparisons among the proposed method and other approaches on different images. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Image** & **[PERSON] et al.** & **[PERSON] et al.** & **[PERSON] et al.** & **[PERSON] et al.** & **Our Method** \\ \hline Lena & 53.75 & 63.17 & 66.84 & 71.30 & **69.62** \\ Baboon & 50.47 & 55.81 & 58.59 & 70.78 & **57.90** \\ Boat & 52.07 & 60.28 & 64.63 & 70.96 & **64.97** \\ Peppers & 50.14 & 61.14 & 64.93 & 70.94 & **63.61** \\ Aiprplain (F-16) & 54.46 & 63.29 & 66.68 & 71.28 & **66.21** \\ House & 54.11 & 67.52 & 72.41 & 72.32 & **68.51** \\ \hline Average & 52.50 & 61.87 & 65.68 & 71.26 & **65.14** \\ \hline \hline \end{tabular}
\end{table} 
Table 11: Comparison of PSNR (dB) between the proposed method and the methods of [PERSON] et al. [46], [PERSON] et al. [47], [PERSON] et al. [21], and [PERSON] et al. [5] for a capacity of 1000 bits. Comparison between the Proposed Method and the Different Embedding Methods with Different Octant Embed Number  
In this subsection, the variations in image quality under different embedding capacities between the proposed method and the different embedding methods are compared. The different embedding methods are generated by reducing the octant embed number of the 3D-PEH in the proposed method. The comparison results are shown in Figure 9.