how to change midi file to piano roll using pretty_midi with the right sample rate?

Question

and what do the "start" and "end" respresent for? I want to sample the midi with time step of 16th notes,how do i do? I think maybe duration of notes are not invariant for each note,I use get_duration() to test durations

Answer 1

The duration of each note is not saved as a note value e.g. whole note, half note, but rather each note has a start and end value. You can use the values you get from get_duration() and calculate the note value with the tempo of the song. Regarding your other question, I don't really understand what you are trying to do. Maybe you could specify your question furthermore.