Need to replace all note values with repeated notes to the same total length

Is there a simple and fast (automatic?) way of replacing all notes longer than, say, semiquavers, with their full value in fast repeated notes? For slightly abstruse midi reasons I want to convert an entire full score so that all note values are very small. It's important that they should not be tied but have distinct attacks (ie a minim would need to be written as eight semiquavers, possibly even in demi-semiquavers). Please don't ask me why it's necessary, or tell me that it's very poor notation. It has a very specific purpose...

It's the kind of thing that ought to be possible with a plug in, I'd have thought. But I can't find anything and have no expertise in building such things.