Adaptive Media Streaming to Mobile Devices: Challenges, Enhancements, and Recommendations

Figure 12

Box plot of acceptance scores for compression, resolution, and frame rate adaptations. The central box spans the interquartile range, with minimum and maximum scores illustrated by “whiskers” to the left and right. Within the box, the bold line corresponds to the median, whereas the dotted line represents the mean acceptance score. The resulting bitrates are also included for each step. The first bitrate is when using I-frames only, which is used in the subjective assessments in order to maintain focus on the given quality parameters and avoid irrelevant artifacts. A real-world scenario would include interframe coding (like IBB* used in the second bitrate) giving a lower rate (we did not observe any visual difference between the I and IBB videos); these rates are comparable to the rates observed in the Comoyo analysis given in Section 3.