One easy optimization for CPU usage is to make sure your inbound video matches your highest output quality.

The highest bitrate, resolution and framerate quality you have configured in Owncast to offer your viewers should match what you’re sending Owncast in your broadcasting software to reduce the amount of extra CPU work it needs to do. Start with your highest quality matching your broadcasting software and then go from there. Lower qualities, of course, should be offered for people with slower network connections or are geographically distant.