Usually, you'd call it to launch a script which in turn can either create a new comp or load an existing one and modify some tools (Loader/Saver) and render it. You'll probably need to make some adjustments to set up the render range correctly depending on your input footage and it might be difficult to set up quicktime codec settings without the GUI (although there are ways, like doing it in the GUI and saving the resulting saver's settings somewhere so you can load them with your script).
If you don't need anything special (like a slate or a frame counter overlay) why not use a command line tool like ffmpeg to do the transcoding? It'll be something like
- Code: Select all
ffmpeg -i "your_sequence.%05.png" your_movie.mov
plus one or two parameters for the codec.