Suppose I have some footage at 30FPS that I'd like to have a copy at 60FPS with tween frames generated by interpolation (at this point I don't care too much about potential quality or artifacts.) And suppose I'm working on a tight budget, so I'd need stand-alone software that's free, or free plugins to other software that's free1. What options are available at this (lack of) price point?
Through my own Googling, the only thing I've been able to find is: Convert videos to 60fps. Unfortunately the software doesn't work for me (after installation, it won't open! :D), and after tons of troubleshooting I'd rather look for a different method.
I know that there are things like Twixtor out there, but right now they're beyond my budget, so any suggestions would be appreciated.
1. I'm willing to hear solutions that do involve money, but the cheaper the better!