## 4 Results and Discussion
### Performance Evaluation
#### 4.2.1 \"Coastguard\" Video Sequence  
From Table 2, we can observe that in most cases, DIVCOM gives a better average PSNR than DIS, while PDIVCOM gives a better average PSNR than DIS in all cases. PDIVCOM outperforms DIVCOM for lower values of \(\mathbf{Q_{m}}\), while DIVCOM outperforms PDIVCOM at higher values of \(\mathbf{Q_{m}}\). In terms of coding efficiency, the coding rate of DIVCOM is better than DIS by between 0.687 kbps to 8.05 kbps, while the coding rate of PDIVCOM is better than DIS by between 1.49 kbps to 8.955 kbps. However, closer analysis at the frame-to-frame level reveals that the RD performance of the proposed codecs is reduced in some frames of this video test sequence. Even so, the decrease in PSNR is small when taking into consideration the improvement in the coding rate. Table 3 presents the results for the Wyner-Ziv (WZ) coder part for decoding WZF. For DIVCOM, the average PSNR gain per WZF over DIS ranges from 0.0521 dB to 0.36 dB, while for PDIVCOM, the gain ranges from 0.039 dB to 0.3323 dB. The average channel-decoding rate results indicate that DIVCOM achieves an average coding efficiency value between 101 bits to 1.151 kbits, whereas the average coding efficiency of PDIVCOM ranges from 219 bits to 1.28 kbits. At the individual frame level, the RD performance of the proposed codecs is degraded in some frames. However, overall, these codecs perform well for most of the frames in the test sequence. From Table 3, we can see that DIVCOM gave a negative average PSNR gain for quantization point 3. The reduction in performance is due to the CNM parameter in the reconstruction process. Even so, the average decoding rate indicates that better coding efficiency is achieved by DIVCOM. For the higher quantization points, the average coding rates of DIVCOM and PDIVCOM are close to that of DIS because, at these higher points, a variant coding rate behavior is noticed for the proposed codecs. For some frames of the sequence, a bit rate per frame that is close to or higher than DIS is achieved; however, higher coding efficiency is attained for most of the frames. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{\begin{tabular}{c} **Video** \\ **Sequence** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Quantization** \\ **Matrix,** \\ **Qm** \\ \end{tabular} } & \multicolumn{3}{c}{\
\begin{tabular}{c} **Average PSNR** \\ **(dB)** \\ \end{tabular} } & \multicolumn{3}{c}{
\begin{tabular}{c} **Coding Rate** \\ **(kbps)** \\ \end{tabular} } \\ \cline{3-8}  & & & **DIS** & **DIVCOM** & **PDIVCOM** & **DIS** & **DIVCOM** & **PDIVCOM** \\ \hline \multirow{6}{*}{Coastguard} & 1 & 32.0616 & 32.0867 & 32.0978 & 417.431 & 416.744 & 415.934 \\ \cline{2-8}  & 2 & 32.97 & 32.9945 & 33.008 & 488.7012 & 487.3013 & 487.1401 \\ \cline{2-8}  & 3 & 34.455 & 34.4520 & 34.4740 & 614.1899 & 612.8306 & 612.5757 \\ \cline{2-8}  & 4 & 34.9146 & 35.009 & 34.974 & 722.3970 & 718 & 717.7109 \\ \cline{2-8}  & 5 & 35.8749 & 35.9899 & 35.9942 & 825.1416 & 818.6396 & 817.7002 \\ \cline{2-8}  & 6 & 36.35 & 36.5285 & 36.5175 & 937.7612 & 929.7104 & 928.8057 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Visual quality and rate performance evaluation of different codecs for “Coastguard” video sequence at frame rate of 15 Hz. Figure 2 depicts the experimental results in the form of RD performance carried out with Intra H.264, DIS, DIVCOM, and PDIVCOM on the \"Coastguard\" video. It can be seen that for all quantization points, the performance of DIVCOM and PDIVCOM is comparable to DIS. For low quantization points, the DIVCOM gives a coding efficiency of roughly between 1 and 2.5 kbps along with a significant improvement in the PSNR. The PDIVCOM also shows almost the same performance trend in both coding efficiency and PSNR. At higher quantization points, both DIVCOM and PDIVCOM outperform DIS. DIVCOM achieves a coding efficiency of up to 8 kbps and an improvement in PSNR of 0.18 dB over DIS.