What ABR algorithm does VideoJS use

Question

I configured multiple resolution/bitrate combinations for a livestream using HLS, the streams plays well/stable in few certain regions but has lot of resolution cycling in other regions. Later I added support for manual resolution selection, so users could use a resolution that worked fine for them, we have observed that even though they have chosen the highest resolution/bitrate it worked fine. I guess (may be wrong) the ABR algorithm was too sensitive to the network state and frequently switched bitrates

1. Can you please point me to the ABR algorithm that VideoJS use?
2. Is it possible to adjust the sensitivity of ABR?

Answer 1

There is a description of how the ABR algorithm works in video-js available in their docs: https://github.com/videojs/http-streaming/blob/main/docs/bitrate-switching.md

As listed in the docs, you can override the ABR algorithm completely with your own by providing your own selectPlaylist function, but based on your description I think using the https://github.com/videojs/videojs-contrib-quality-levels plugin will allow you to tune the ABR selection to your needs