Use sendcmd filter in PyAV

[caffeinism]

Hello? I'm a user who enjoys using PyAV. FFmpeg is a very powerful tool, and I always use it frequently. Python is a very flexible language. However... when using PyAV, I can only achieve movements that are as rigid as FFmpeg.

For example, I want to dynamically change the size of something or execute filters with dynamic parameters. But reconfiguring a filter after it's been set up seems very difficult. So, is there any way to dynamically change filters within PyAV using a tool like sendcmd?

Currently, whenever the target value changes, I recreate the entire graph and rebuild it for use. But this is... very slow. Is there any existing method to improve this?

[caffeinism]

Upon checking, it seems sendcmd only reads data up to the point of graph construction, even when reading from stdin or a named pipe. There is a zmq filter, but it isn't built into pyav binary.