Accessibility: Adjust Subtitle Text Sizes

The Goal?
The goal for this exercise is to help viewers who are having trouble in reading the current displayed subtitles. Some users (minority) commented on the current subtitle text size that are not large enough to be read.

How? Making use of Material Design's component like the range slider to allow the viewers to adjust the subtitle text size to fit their comfortable level. We placed the new function together with other Subtitle related actions to make sure that it is contextually meaningful and easy to understand.

Other Challenges:
1. Magnification and large text can break the video player's layout.
2. What is the default (ideal) text size for first timer users?
3. Text size alone is not enough, what is the ideal Typeface for video subtitles in terms of legibility?
4. Also need to consider other non-latin languages too i.e. Chinese, Arabic etc.
5. Need to check the versatility of webVTT subtitle text formatting in terms of the feasibility part.

Thanks! - Teo Choong Ching

(Viki's player design credit to Borrys Hasian)