MIDI specification on SMF is a bit confusing regarding storing a tempo map in a MIDI file:
for a format 1 file, the tempo map must be stored as the first track
Does it mean a first track chunk must contain only
tempo map? Or other events allowed there, but tempo map for the first chunk only?
Another info from the spec:
tempo maps (which describe the tempo throughout the track, and may also include time signature information, so that the bar number may be derived)
So tempo map can contain only Set Tempo and Time Signature events?