ffplay

**Is your feature request related to a problem? Please describe.**

This library is awesome, it's amazing to be able to run `ffmpeg` via WASM. There are lot of interesting applications of this already.

I'm curious if it would be possible to compile `ffplay`, potentially as its own package. It would be very interesting if we could see real-time outputs from `ffmpeg` filter chains, in the browser. But I have no idea if this is feasible.

**Describe the solution you'd like**

Really just curious. Have you tried it out of curiosity? Or is it perhaps a non-starter, and performance would not be good enough?