I'd call that 'processors'. Something like 'load image' could be called 'source' and 'save image' a 'sink'. Of course I'm biased since I have been using such naming schemes for years in signal processing software
We will discuss this internally. We have not given to much though on nomenclature. It is mostly historical use.
Under the hood we have here ImagePlay 6.0 which is a rewrite of good old trusty Borland C++ code.
"Tools" or "functions" probably work and fit in well with descriptions of processing in graphics packages; "processes" seems fine to me (like the suite from http://processing.org ).
Yes. Functions or methods or procedures is preferable to processes. "Processes" implies threads or independently executing activities, like multiprocessing.
For what I know, "processes" is an established term in component-based paradigms like flow-based programming, which this system seems to have many similarities with.
I guess it's what you are used to. Back in the days I toyed with music production and actual hardware units usually had names like synthesizer/flanger/phaser/equalizer/mixer/processor (so not the verbs like synthesize/flange/phase/equalize/mix/process) and I just took over those. There might be counter examples of course but I cannot come up with one atm.