# Load Balancing Strategies for Slice-Based Parallel Versions of JEM Video Encoder
## 3 Parallel Approaches
### Asynchronous Algorithm: JEM-SP-ASync
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & & \multicolumn{5}{c}{**Computational Time (s.)**} \\ \hline Video & & QP & QP & QP & QP \\ sequence & NoT & 22 & 27 & 32 & 37 \\ \hline \multirow{4}{*}{BQSQ} & 2 & 5368 & 4215 & 3354 & 2629 \\  & 3 & 3556 & 2915 & 2244 & 1781 \\  & 4 & 2695 & 2695 & 2695 & 2695 \\  & 8 & 1449 & 1449 & 1449 & 1449 \\ \hline \multirow{4}{*}{PART} & 2 & 22,302 & 18,668 & 14,968 & 11,172 \\  & 3 & 15,343 & 12,730 & 10,216 & 7532 \\  & 4 & 11,613 & 9677 & 7693 & 5737 \\  & 5 & 9403 & 7729 & 6288 & 4748 \\  & 6 & 7891 & 6568 & 5332 & 3997 \\  & 7 & 6807 & 5761 & 4513 & 3386 \\  & 8 & 6000 & 5039 & 4040 & 2990 \\  & 10 & 4769 & 4087 & 3176 & 2435 \\ \hline \multirow{4}{*}{FOUR} & 2 & 23,893 & 17,072 & 12,822 & 9247 \\  & 3 & 16,392 & 11,909 & 8811 & 6401 \\  & 4 & 12,311 & 9143 & 6624 & 4811 \\  & 5 & 9569 & 7195 & 5263 & 3862 \\  & 6 & 8306 & 6046 & 4482 & 3325 \\  & 7 & 7019 & 5140 & 3818 & 2791 \\  & 8 & 6220 & 4578 & 3367 & 2509 \\  & 9 & 5473 & 4000 & 2983 & 2182 \\  & 10 & 5057 & 3703 & 2714 & 2029 \\  & 12 & 4341 & 3144 & 2370 & 1723 \\ \hline \multirow{4}{*}{PARK} & 2 & 82,978 & 58,401 & 40,028 & 25,722 \\  & 3 & 57,119 & 40,202 & 27,935 & 17,760 \\  & 4 & 43,445 & 30,449 & 21,543 & 13,332 \\  & 5 & 34,683 & 23,956 & 16,803 & 10,840 \\  & 6 & 28,754 & 20,416 & 14,461 & 9007 \\  & 7 & 24,939 & 17,967 & 11,961 & 7656 \\  & 8 & 21,809 & 15,356 & 10,624 & 6805 \\  & 9 & 19,275 & 13,767 & 9508 & 6034 \\  & 10 & 17,512 & 12,408 & 8499 & 5666 \\  & 11 & 16,084 & 11,304 & 8064 & 5105 \\  & 12 & 15,207 & 10,695 & 7347 & 4750 \\ \hline \hline \end{tabular}
\end{table} 
Table 15: Computational times (s.) for Algorithm JEM-SP-ASync. from one slice to the next, whereas in our parallel algorithms, these variables have the same initial values for all slices. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline  & & & \multicolumn{6}{c}{**Bitrate (Kbps)**} \\ \hline Video & NoT and & Slice & & QP & QP & QP & QP \\ sequence & slices & size & & 22 & 27 & 32 & 37 \\ \hline  & & & Seq. & 13,024 & 8652 & 5578 & 3474 \\  & 2 & 4 & Par. & 12,579 & 8361 & 5356 & 3370 \\  & & & Diff. & \(-\)3.4\% & \(-\)3.4\% & \(-\)4.0\% & \(-\)3.0\% \\  & & & Seq. & 13,366 & 8855 & 5736 & 3563 \\ BQSQ & 4 & 2 & Par. & 12,640 & 8410 & 5393 & 3398 \\  & & & Diff. & \(-\)5.4\% & \(-\)5.0\% & \(-\)6.0\% & \(-\)4.6\% \\  & & & Seq. & 13,508 & 9113 & 5898 & 3644 \\  & 8 & 1 & Par. & 12,826 & 8548 & 5495 & 3483 \\  & & & Diff. & \(-\)5.0\% & \(-\)6.2\% & \(-\)6.8\% & \(-\)4.4\% \\ \hline  & & & Seq. & 45,454 & 28,760 & 17,506 & 9660 \\  & 2 & 14 & Par. & 45,291 & 28,643 & 17,362 & 9675 \\  & & & Diff. & \(-\)0.4\% & \(-\)0.4\% & \(-\)0.8\% & 0.2\% \\  & & & Seq. & 46,018 & 29,001 & 17,678 & 9736 \\ PART & 4 & 7 & Par. & 45,499 & 28,794 & 17,468 & 9750 \\  & & & Diff. & \(-\)1.1\% & \(-\)0.7\% & \(-\)1.2\% & 0.1\% \\  & & & Seq. & 46,559 & 29,558 & 17,833 & 9810 \\  & 8 & 4 & Par. & 45,689 & 28,919 & 17,552 & 9814 \\  & & & Diff. & \(-\)1.9\% & \(-\)2.2\% & \(-\)1.6\% & 0.0\% \\ \hline  & & & Seq. & 27,225 & 16,817 & 10,498 & 6513 \\  & 2 & 30 & Par. & 26,866 & 16,631 & 10,398 & 6464 \\  & & & Diff. & \(-\)1.3\% & \(-\)1.1\% & \(-\)1.0\% & \(-\)0.8\% \\ FOUR & 4 & 15 & Par. & 27,712 & 16,871 & 10,575 & 6595 \\  & & & Diff. & \(-\)1.9\% & \(-\)1.7\% & \(-\)1.5\% & \(-\)1.1\% \\  & & & Seq. & 28,180 & 17,397 & 10,960 & 6831 \\  & 8 & 8 & Par. & 27,506 & 17,106 & 10,746 & 6719 \\  & & & Diff. & \(-\)2.4\% & \(-\)1.7\% & \(-\)1.9\% & \(-\)1.6\% \\ \hline  & & & Seq. & 49,209 & 26,911 & 14,227 & 7118 \\  & 2 & 68 & Par. & 49,084 & 26,873 & 14,222 & 7132 \\  & & & Diff. & \(-\)0.3\% & \(-\)0.1\% & 0.0\% & 0.2\% \\  & & & Seq. & 49,288 & 26,987 & 14,284 & 7154 \\ PARK & 4 & 34 & Par. & 49,218 & 26,983 & 14,301 & 7182 \\  & & & Diff. & \(-\)0.1\% & 0.0\% & 0.1\% & 0.4\% \\  & & & Seq. & 49,452 & 27,135 & 14,395 & 7232 \\  & 8 & 17 & Par. & 49,468 & 27,166 & 14,436 & 7271 \\  & & & Diff. & 0.0\% & 0.1\% & 0.3\% & 0.5\% \\ \hline \end{tabular}
\end{table} 
Table 16: Comparison of bitrate.