If stack16 has no special metadata the best thing I can think of is to add stack16 to "alias format filter", or make another "unstack" filter exactly for this. Filter is good explicit way to express the intent and control it.
I`d like to hear who actually wants to use this and for what (simply transferring from avs to ffmpeg?)
My own interest would be to study various denoising filters (in some future).
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Thanks for appreciation. My fork is still ridiculously hard to find and the download rate on sourceforge is vanishing.
I wish I could stick a link onto official vd sourceforge
btw would it be appropriate to move part of this thread related to avs editor to Avisynth development subforum?