About

This script helps convert an existing video file to a vp9 webm of set size with ffmpeg, which really helps if you use websites or services such as Discord which have an upload filesize limit. It uses a simple 2pass equasion:

(Desired Size in Megabytes * 8192) / Total Length in Seconds = Available bandwith

The audio has a set bandwith of 64k (libopus) and this value is subtracted from available bandwith to calculate video bitrate.

The ffmpeg command used is mostly copied from this reddit post because the default libvpx-vp9 settings suck and I don't have enough time to delve into these things myself.

Options

• -i File input (mandatory for obvious reasons).
• -u New frame height. Width is calculated by aspect ratio automatically by ffmpeg.
• -s Desired size in MB. Default is 8, because discord is a thing.
• -o Output filename. Keep in mind that if a file with the same name already exists, the script will exit.

Other stuff worth mentioning

Please notify me if you spot any glaring issues in the script, I'm not a pro bash scripter so they might be there.

Also feel free to make any requests ;)