@scharfis_brain
The general idea is definitely possible. If I follow correctly what you really want is a filter that takes a hybrid input stream, determines what parts are what (24p/30p/60i) and then chooses between already converted streams as needed. That really isn't where I was headed (atm the conversions are also done inside tfm/tdecimate for everything but 60i where the user will need to give tdecimate an already bobbed stream). However, your idea could be done by just ripping out the detection from tfm/tdecimate and making a filter out of that.
Actually, your idea is pretty good... the big thing standing in the way atm is the detection of 60i/24p/30p, which is heavily integrated into the actual conversions right now. I've mainly been ripping off the code from some ivtc filters I wrote before and they only did 24p/30p detection so if there were combed frames after field matching they were deinterlaced. Trying to cram 60i detection into that framework is not working well (i.e. if an output frame from tfm is combed it is 60i). Going back and doing the detection on the field level (look for duplicated fields to separate 60i from 24p/30p) would probably work better.
One thing I don't get in your example though is the 47.952 framerate? If the final output framerate is 23.976 why not just have mvconvertfps(23.976), leave the 24p alone and then input those? Most likely I am missing something here
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