A recorder cannot, by definition, record 'sections'. There is a 1:1 mapping between what you consider a section and a recorder. You can't 'push' frames from a recorder to another. Recorders can only record frames, not load them and give to something else. Say you have `n` sections, your only option is to record those `n` sections with `n` recorders (given the 1:1 mapping) and get `n` section videos. You must then figure out how to concatenate those `n` sections into 1 final video, which is where FFmpeg comes in. NatCorder does not do any post-processing; it simply records to a video file and that's it.