VSE: Can you make a script to code in more filters? (add/multiply/subtract) So specifically in blender you have 3 settings really: add/subtract/multiply. Image editors such as gimp give you these and a total of 21 setting.

Are these settings in blender just a mashup of modifier settings applied across 2 strips? Or is there some kind of generic coding that all programs share for these settings? Add/subtract/multiply are found across all programs really for example.
I was just curious if the other filters from gimp could be put into blender via a script.

Kinda open ended given I don't know how to script for blender, but just curious if any insights. If each filter has a generically shared code then I'm guessing you could just make a new filter name for blender and plop in these codes for each?
Turns out your build of Blender may be old. 
They were updated as of this commit https://developer.blender.org/D2872
In fact there are a bunch of new blend types available.