# Fuzzy-Based Quality Adaptation Algorithm for Improving QoE from MPEG-DASH Video
## 6 Simulation Results
### Dataset 1
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Adaptation Algorithms** & **Proposed** & **FDASH** & **DBT** & **QLSA** & **DASH-Google** \\ \hline Average Video Rate (kbps) & 1307.55 & 1196.86 & 1223.38 & 1205.04 & 1216.87 \\ Switching Ratio & 0.28 & 0.05 & 0.10 & 0.32 & 0.45 \\ Inefficiency & 0.16 & 0.41 & 0.28 & 0.23 & 0.19 \\ Average of Switches & 615.56 & 788.79 & 596.77 & 607.66 & 521.73 \\ (kbps) & 1145.33 & 834.32 & 1166.78 & 992.39 & 930.74 \\ QoE & 3.20 & 1.81 & 3.31 & 2.63 & 2.42 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Performance of the algorithms with a buffer size of 15 s and segment duration of 2 s.  
Figure 7: Comparison of (**a**) rebufferings per client, and average number of interruptions, and (**b**) average buffering time when the clients downloaded Dataset 1. The buffer size and segment duration were set to 15 s and 2 s, respectively. Next, we set the buffer size and segment duration to 30 s and 4 s, respectively. Although the buffer size increased, the ratio of buffer size to segment duration was the same as in the previous experiment. Table 5 shows that the proposed algorithm achieved a high video rate by efficiently utilizing the available bandwidth. Moreover, the proposed algorithm avoided playback interruptions. Table 5 shows that the proposed algorithm achieved the highest QoE and MOS values. The DBT algorithm achieved the highest QoE and MOS values in the previous experiment. However, because the buffer size increased, the performance of the algorithm degraded. The algorithm mitigated unnecessary video rate switches and avoided playback interruptions at the expense of a low video rate. As explained earlier, the DBT algorithm divides the buffer level into predefined buffer thresholds. As the buffer fills up, the algorithm selects video rates more aggressively. The DBT algorithm does not adapt the playback buffer thresholds as the buffer size changes. As the buffer size increases, the distance between the predefined thresholds also increases. This reduces the switching ratio but at the expense of a lower video rate. Table 5 and Figure 8 show that the FDASH algorithm achieved the highest video rate and the lowest switching ratio, but at the expense of a large number of rebuffering events. As a result, the QoE of the FDASH algorithm degraded. The QLSA and DASH-Google algorithms achieved high video rates but at the expense of a large number of video rate switches. Next, we increased the buffer size to 60 s. Table 6 shows that the proposed algorithm achieved the highest video rate, efficiently utilizing the bandwidth while avoiding playback interruptions. The proposed algorithm achieved the highest QoE and MOS values. The FDASH algorithm achieved a high video rate while mitigating the frequency of video rate switches. Figure 9 shows that FDASH was the only algorithm to experience playback interruptions. As a result, the FDASH algorithm had a lower video rate than the proposed algorithm. Table 6 shows that the FDASH algorithm achieved the second highest QoE value; however, its MOS value is the second lowest. The reason is that the playback interruption events heavily impact the MOS values. The DBT algorithm had the fewest  
Figure 8: Comparison of (**a**) rebufferings per client and average number of interruptions, and (**b**) average buffering time when the clients downloaded Dataset 1. The buffer size and segment duration were set to 30 s and 4 s, respectively. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Adaptation Algorithms** & **Proposed** & **FDASH** & **DBT** & **QLSA** & **DASH-Google** \\ \hline Average Video Rate (kbps) & 1328.39 & 1397.88 & 1033.22 & 1269.27 & 1285.14 \\ Switching Ratio & 0.29 & 0.09 & 0.13 & 0.38 & 0.44 \\ Inefficiency & 0.16 & 0.29 & 0.33 & 0.23 & 0.19 \\ Average of Switches (kbps) & 765.51 & 285.99 & 668.30 & 551.19 & 534.21 \\ QoE & 1106.78 & 511.92 & 887.51 & 1030.42 & 1021.27 \\ MOS & 3.45 & 1.61 & 2.68 & 3.3 & 3.28 \\ \hline \hline \end{tabular}
\end{table}